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Talk:Troy weight

Which Definition of Inch
In the article it says:

"One cubic inch of distilled water, at 62 °F (17 °C), and at a barometric pressure of 30 inches of mercury, was determined to weigh 252.458 troy grains (gr)."

Which definition of the cubic inch and inch is intended? The inch has changed values considerably throughout history, the latest in 1960 when it was defined as 0.0254 m. This would have noticeable effect on the all of the non-metric units.

Why not make one more change? Define the Troy ounce as 31.25 g exactly. This way there would be 16 ounces in 500 g and 32 in a kilogram. It will also be easier to weigh out troy ounces on a gram scale. —Preceding unsigned comment added by 70.187.73.207 (talk) 17:55, 27 February 2010 (UTC)

I think the paragraph "One cubic inch of distilled water, at 62 °F (17 °C), and at a barometric pressure of 30 inches of mercury, weighs 252.458 troy grains (gr)." needs to be removed from this article, I don't see what it has to do with Troy weight! It's more like the definition of an inch, but as the inch varied until 1958 it does not apply, this particular reference is from 1840.Metricmike (talk) 03:12, 2 October 2011 (UTC)

 * I removed the offending paragraph. Zyxwv99 (talk) 21:34, 13 November 2011 (UTC)

 * The variation of the imperial yard, relative to the metre, would vary the metre from Kater's value of 39.37079 inches, to a value closer to 39.370113 inches. The effect on volume is 51 ppm.  This would vary, eg 252.458 to 252.471 over the historical era.  The actual value of 252.458 was a determination from 1820's sanctioned at law for converting gallons to cubic inches.  A new measurement in 1898 gives 1 cu inch as 252.325 grains troy, this is the basis of the modern gallon of 4.54609 cu in.

 * "grains troy" distinguishes from other grains, like "grains tower", "grains avoirdupoise" (which was proposed but never used), and "baker's grains". The avoirdupoise dram was to be divided into 30 grains avoir, or into 28 grains in Baker's Tables (in notes on rifle guns).  Tower grains are 1/640 tower ounce, or 1/682.666 troy ounce.  avoirdupoise and tower grains were current when that particular quote was written.

 * The inch did not so much vary. What happens is that the standard changed relative to the metric one, and that the extent of the variation has little effect except on geodetic surveys, and on making guns.  Similar variations exist in metric (german legal metre).  Wendy.krieger (talk) 07:34, 11 April 2012 (UTC)

Who defined the grain in terms of the gram? When? -- Anon.

 * Thomas Corwin Mendenhall. April 5, 1893. See Mendenhall Order Zyxwv99 (talk) 01:53, 21 November 2011 (UTC)

 * The relationship of 1 pound avoirdepoise is 7000 troy grains, was first a conversion relation between a particular averdepoise and troy scale, and then the definition of the pound, (up to 1834, the standard of weight was two troy pounds), and then the definition of the grain (the new standard was 7000 grains). The definition of the grain in grams was made in 1959 by international agreement that the grain would be 64.7989 or 64.79891 milligs, this half-way between the Seer's 1922 and Broch 1880 determinations.  The latter was selected.  The US value derives from Broch's determination of the pound in grams.  Wendy.krieger (talk) 08:12, 13 April 2012 (UTC)

"ounce of gold weighs more than an ounce of feathers" - be careful with that "weighs" word. Unless you weigh in a vacuum, a gram of gold weighs more than a gram of feathers, too. Kwantus 20:23, 2004 Dec 8 (UTC)
 * Tried to fix mess. How's it look? Rossumcapek 02:04, 13 Dec 2004 (UTC)

In the troy system, there are 20 pennyweights in an ounce, and 12 ounces in a pound. In pre-decimalisation British currency, there were 20 pence in a shilling, and 12 shillings in a pound. I'm pretty sure there were other currencies with these subdivisions as well. I'm wondering if there's any historical basis for this; if anyone knows, it could make a good addition to the article. Izzycat 23:45, 18 February 2006 (UTC)

British currency was: 4 farthings to a penny; 12 pennies to a shilling; 2 1/2 shillings to a half crown; 5 shillings to crown; 20 shillings to a pound; 21 shillings to a guinea. Easy, huh?

 * The currency reform of King Offa replaced the scetta with a silver penny, derived by dividing the moslem dirhem into two coins. The resulting coin is about the size of a silver threepence, or about half the size of a dime.  The shilling was then set at twelve pence (in place of smaller and larger values), and the pound as twenty shillings.  Also, the ounce was set to twenty pence.  In this time, and for 300 years there after, a (tower) pound of silver was a currency pound.  The first mention of 'troy' in an act was 1309, but elsewhere this is implied as the tower pound (since the 480 grain ounce did not appear until much later). Wendy.krieger (talk) 08:12, 13 April 2012 (UTC)

If troy is a system of mass and avoirdupois is a system of weight (which is what the entries say) there should be a disclaimer somewhere that we're talking about (say) sea level on the earth.

It should be mentioned that troy measures are derived from Troyes, not Troy. I don't have any better sources though than the other Wikipedias (e.g. German and Russian). --Oop 18:33, 11 November 2007 (UTC)

 * One etymology for 'troy' is the market town in france (troyes). This is the usual etymology given in dicitionaries, but given as tentivite.  The actual weight is again based on an moslem gold prototype of 48 grains troy, which may have been traded at troy.

This has to be one of the dumbest suggestions I've heard for the use of "Troy". It came from Troyes in France? WTF? What muppet came up with that? No. Troy comes from the Germanic root of English. Meaning true. A troy pound is a true pound. Germans still use the word today to mean faithful. You can look it up in any German dictionary. — Preceding unsigned comment added by 87.160.169.126 (talk) 12:55, 28 April 2013 (UTC)

 * However, Colonel Watson "British Weights and Measures" suggests a different etymology (pp 32-33). Having established that the words 'troy' and 'avoirdupois' were in use before their scales, the names could not have followed the weights.  Instead, 'troy' relates to dialectic 'troi' balances, and 'avoirdepois' to 'goods of weight'.  troy weight is then weights by scales (gold, silver, gems, medicines), while avoirdepois is goods of weight (every thing else).

 * The original metric system made the distinction between the two kinds of weight (grave avoirdepois vs gram troy), but the intervention of the 'system usuelle' preempted the grave-scale, and by the time it came to eliminate the system usuelle, the notion of dual weights became somewhat dated. That's why we have kilograms instead of graves.  Wendy.krieger (talk) 06:44, 12 April 2012 (UTC)

Millesimal fineness
How does the Troy ounce translate into a millesimal fineness figure? I'm trying to establish if all the 'oz' mentions in 16th century coin were, in fact, referring to Troy ounces. According to John Chown (A History of Money from AD 800, page 43, on Google Books) the 'Troy Pound' replaced the 'Tower Pound' in 1526 as the measurement for the Royal Mint. What I need to know from this article is was the Troy ounce the standard ounce in all money in Tudor England after 1526? Thanks. 86.42.102.87 (talk) 23:52, 16 April 2008 (UTC)
 * I am assuming you are talking about English coins. While it's not really a source on coins, I think you should read Chapter I.4 of Connor and Simpson: "Weights and Measures in Scotland". This book seems to contain the most correct and up to date information on English measures of the time. In short: English and Scottish measures were essentially the same if you only look at the ounces (not at the number of ounces in a pound), and so far as mint weights are concerned there was only the tower ounce of 450 troy grains (but probably divided in 480 tower grains), superseded by the troy ounce of 480 troy grains. However it seems that the weight of a grain was increased from 64.76 mg to 64.80 mg in the 18th century, as the result of an erroneous decision after the official standard was lost. However, since the error consisted in using the faulty standard that was in use at the mint as the base for the new standard, you should really read the book and the paper Simpson and Connor: "The mass of the English troy pound in the eighteenth century" if you need it as exactly as that. (I am also not sure I am summarising everything correctly, as it's rather late for me.)
 * I don't see the connection to fineness. I think for silver in this period it was always "sterling", but at the time if they had debased the money by reducing the fineness, the meaning of the word would have been adapted, so I just don't know about that. --Hans Adler (talk) 01:18, 17 April 2008 (UTC)

 * Fineness for silver was in ounces of 20 dwt, pure = pound. Sterling was 11 oz 2 dwt fineness, or 11.1/12.  Purity of gold was in carats of 4 grains, viz pure = 24 carats, 1 carat = 4 grains.  The arab dirhem or mitkal weighs 24 carats, as did the solidus at one stage weigh 24 carats.  A coin of weight 24 carats would be say, the weight of two dimes (US money), or a nickel.  A gold coin would be about the size of a dime (US sixpence). Wendy.krieger (talk) 07:34, 11 April 2012 (UTC)

Scottish system
We need the absolute weight of one of the scottish units. Rod57 (talk) 03:57, 5 December 2008 (UTC)
 * For Scottish weight units I recommend "Weights and measures of Scotland" by R.D. Connor, which contains the results of the latest research. It turns out that even before the forced unification the Scottish units weren't so different from the English units. Mostly there were regional units that were different even within Scotland or England, and there were national units that were "originally" (i.e. dating very far back to the time when the large Scottish cities were founded) the same in both countries. The main difference that evolved over the centuries was that different units were lost, e.g. the English stopped using the ell (previously used primarily for measuring goods traded with Germany) and the Scots stopped using the yard (previously used primarily for measuring land). A further complication was that 19th centuries antiquaries sometimes misread the surviving weight and measure standards (e.g. the ell standard), because the tradition how to use them was lost. The book is really amazing – if I remember correctly, Scotland was trading with Venice in the first millennium! --Hans Adler (talk) 11:10, 5 December 2008 (UTC)

The paragraph on the Scottish system is internally inconsistent or at least unclear as it now reads (5/1/10): “Thus there were 16 drops to the troy ounce, 16 ounces to the troy pound, and 16 pounds to the troy stone.”  Is the standard reference for the Scottish system the troy ounce (480 grains) or the troy pound (5760 grains)? As written, the Scottish ounce would be 1/16 of a troy pound (360 grains), and the Scottish drop would be 1/16 of troy ounce (30 grains). This would then make the Scottish drop 1/12 of a Scottish ounce (30/360). If so, the Scottish system would then lose the implied symmetry of 1/16 of 1/16 of 1/16 of a “Troy Stone.”  [b.t.w., is a troy stone even defined or used elsewhere? And, who would be trading in a mass of a precious metal of that size?] If it were based only on the troy ounce (480 grain) then the Scottish pound would be 16 troy ounces or 7680 grains. If it were based only on the troy pound, the Scottish drop would be 1/16 of 1/16 of a Troy pound or 22.5 grains. In the light of the comment s previously submitted: 01:18, 17 April 2008 (UTC) and 11:10, 5 December 2008 (UTC),   it appears that the details of actual historical standards are unclear.

If the facts are so convoluted and unclear, does the full paragraph on Scottish system even belong in the “Troy weights” article? Perhaps the “Troy Weight” article should only make a passing statement such as, “Incorporation of Goldsmiths of the City of Edinburgh used another system. (See the article on the History of Weights & Measures).”

I would ask those with editorial experience to ponder whether the following statement belongs in the “Troy Weights” or “History of Weights and Measures” article: “In Scotland the Incorporation of Goldsmiths of the City of Edinburgh used a system in multiples of sixteen. Sixteen drops to an ounce and sixteen ounces to a pound and sixteen pounds to a stone. It is unclear exactly how the ounces or pounds actually related to pounds and ounces in the Troy system of weighing precious metals.”

 * The scottish troy pound was 7716 BI grains, but often rounded to 7680 grains. It divides to 16 ounces, of 16 drops of 30 grains, and 16 pounds make a stone.  Denominations of weights tend to run to binary powers, which encourages powers of two in weights.  Wendy.krieger (talk) 07:52, 13 April 2012 (UTC)

Additionally, before an actual reference is made as to how the Scottish system related to the Troy system, the detail of the primary reference (See Assay-Master's Accounts, 1681–1702, on loan from the Incorporation to the National Archives of Scotland.) should be consulted more precisely. MDB341 15:59, 1 May 2010 (UTC)

I have removed this irrelevant piece:- Ettin is archaic English for giant, and one wonders whether Edinburgh was so named for an unofficial reputation as the "City of Giants." You can recognize a cognate of ettin in the Icelandic word jötunn, which means giant (Jötunnheim was the realm of the giants in Norse mythology, Old Norse being all but identically the same language as modern Icelandic.) Ceartas 21:03, 9 July 2010 (UTC)

 * Scottish troy measure is unrelated to either of the English systems. 'troy' as an appellation to a weight system first appeared with the tower system in 1309.  The troy oz of 31,104 gramms appeared somewhat later: thus troy can not refer to the town in france, but is a method of weighing of precious things by balance.  Wendy.krieger (talk) 06:44, 12 April 2012 (UTC)

Reasons for Continued Use
I stumbled upon this article while searching for what a Troy Ounce was. One thing I will look into is why the Troy Ounce remains the measure for Gold and other precious medals as opposed to converting to Grams or some other measure. If anyone else has resources or information on this subject I think it would be valuable to the article. Drockel (talk) 19:07, 4 March 2009 (UTC)

 * This question actually comes up a lot. It's for the same reason that railroad tracks are stuck at a certain gauge. If they wanted to switch to a wider gauge, they'd have to tear up all the railroad tracks in the country and start all over again. It's why my computer still runs on X86 technology, and why the human brain is just a thin layer of mammalian tissue stuck onto a reptile brain. Much of the world's gold supply is in the form of 400 oz. (troy) bars of gold, purity usually 0.995. Much of the gold supply of Asia and parts of Africa is in the form of 22-karat 10-tola bars. The tola is a unit of British India equal to exactly 3/8ths of a British Imperial troy ounce. On the other hand, much of the world's gold supply is also denominated in kilograms. Go to Switzerland and buy some gold bars, they almost all come in metric sizes.
 * Zyxwv99 (talk) 02:08, 21 November 2011 (UTC)

Troy Weight
The following moved from User talk:Indefatigable

This system does not measure mass, it measures weight (as the name implies). For example, an item which measures 1 troy ounce on earth will not measure 1 troy ounce on the moon or in free space (because an ounce measures weight). By comparison, 1 gram of a substance will measure 1 gram everywhere in the universe (because it measures mass). —Preceding unsigned comment added by 71.139.9.126 (talk) 22:02, 13 November 2009 (UTC)

 * Please let's not use the term weight: it's ambiguous. You seem to be contending that troy units measure force, rather than mass. This is incorrect: they are mass units. When these units were invented, the only devices that could measure troy units were balance scales. Balance scales measure mass, not force: they give the same reading regardless of the gravitational field (as long it's not zero). Spring scales for measuring force were not invented until many centuries later. Indefatigable (talk) 22:15, 13 November 2009 (UTC)

 * Did you actually, like, read this article before putting forth this pointless contribution? The article is about a system of measurement used primarily for *precious metals*, which have historically been measured with a balance scale that used, well, weights. So contrary to your claim, no, 1 troy ounce measures one troy ounce everywhere in the universe. Today, due to an unfortunate bit of renaming, what we call "mass" we previously called "weight". Troy weight measures mass, because it has been measuring mass before the concept of mass was renamed from weight to mass and "weight" was assigned to a wholly different concept. It would have been simpler for all concerned if "weight" was left as it was and the new concept, now called "weight", was called "heft" instead, and "mass" just left out of English altogether. But we didn't, so now we have the current mess along with unthinking idiots parroting textbook definitions without actually understanding them. D P J (talk) 04:17, 29 February 2020 (UTC)

Well, it really comes down to whether you think a pound of steel is still a pound of steel on the moon. Physicists would say "no". Apparently you would say "yes". To me, this implies that saying troy weights measure mass is, at least, contoversial (if not ambiguous). —Preceding unsigned comment added by 71.139.16.134 (talk) 16:59, 14 November 2009 (UTC)

 * If it's a force, how is that force defined? It's easy to see that it's mass by following the chain of definitions. A kilogram is the mass of an artifact in France. An avoirdupois pound is legally defined as 0.45359237 kg. A troy pound is legally defined as 5760/7000 of an avoirdupois pound, so both pounds are legally mass units. I acknowledge that there is also a unit called pound-force, which is usually abbreviated to "pound", but the troy units have never spawned force units. Only the avoirdupois mass units have spawned parallel force units. Indefatigable (talk) 20:13, 14 November 2009 (UTC)

 * In legal and commercial usage, "weight" means "mass" as physicists understand the term. Zyxwv99 (talk) 21:11, 11 November 2011 (UTC)

 * Why do we get these people who think that the physics use of 'mass', 'displacement' etc supercede all other uses. In metrology, weight refers to what balances measure.  In theory this is moment of force around the fulcrum, but in practice, gravity cancels out, and the balance measures moment of mass.  An equal-arm balance has a direct dependence of mass down to eight significant digits.  Troy weight is weight by balance is always mass. Wendy.krieger (talk) 07:58, 13 April 2012 (UTC)

This page needs a different picture of a gold or silver bar which actually says TROY ounce on it! —Preceding unsigned comment added by 74.71.117.59 (talk) 07:46, 20 February 2010 (UTC)

There is a picture on the Krugerrand which shows it as being '1 oz', it is not usual to give it as troy. Wendy.krieger (talk) 06:44, 12 April 2012 (UTC)

 * I looked all over Google Images and couldn't find any. Furthermore, I hadn't even gotten around to narrowing my search to public domain images. Coins, yes, but not bars. Zyxwv99 (talk) 02:14, 21 November 2011 (UTC)

 * Troy weight is normally implemented by bullion coins. Large weights are usually done in chogs of 32 oz 3 dwt 7 mites troy.  Wendy.krieger (talk) 07:58, 13 April 2012 (UTC)

 * Gold held by central banks is mostly in 400 oz. bars, although in recent decades they've been acquiring more gold denominated in kilograms. This is probably the only reason why the troy system hasn't been discontinued: if it was, central banks would have to melt down trillions of dollars worth of gold and have it re-cast to conform to standard.
 * The reason I haven't been able to find any photos is not that such bars don't exist or haven't been photographed, but that the word "troy" is nowhere to be seen in the photos. That's because, in the world of gold, "ounce" (or "oz.") is presumed to mean "troy ounce."
 * Gold traded on commodity exchanges is typically 100 oz. The buyers are the jewelry, electronics, and dental industries, as well as private investors.
 * As for "chogs of 32 oz 3 dwt 7 mites troy" I've never quite heard of that, although there is something called Mini Gold (33.2 ounces). However, the use of the word "mite" brings up another point: this article fails to mention mint weights. There are 24 blanks to a perit, 20 perits to a droit, 24 droits to a mite, and 20 mites to a grain. These are all part of the troy weight system. Zyxwv99 (talk) 14:17, 14 April 2012 (UTC)
 * Mint weights: Thanks to User:Zyxwv99 for fixing the and giving them some context. --Old Moonraker (talk) 20:30, 21 April 2012 (UTC)

Watson's conjectures
Several weeks ago someone added two paragraphs to this article about Watson's theory on the origin of the troy weight system, one in the Etymology section and one in the History section (second paragraph of Origins subsection). At first I thought this was just another alternative theory. However, after the same material appeared in the Grain (unit) article I became concerned and decided to look into it.

British Weights and Measures as described in the laws of England from Anglo-Saxon Times by Colonel Sir C M Watson KCMG, CB, MA, late Royal Engineers, (1910) is a twenty-thousand-word booklet with no footnotes, end notes or bibliography. In the preface, Watson describes it as "popular" clearly in the sense of not claiming to be scholarly. The full text of Watson's book can be found at archive.org The relevant details can be found on pages 32-34.

Watson claims that the word "troy" means "balance" or "scale" (i.e., equal-arm as opposed to auncel scale) and goes back to Old English. (An auncel is a scale with a fixed weight and movable fulcrum.) However, the only evidence he cites is Wright's English Dialect Dictionary. In order for this claim to carry weight, Watson would need to be a credentialed linguist, dig up more evidence, publish the results in a peer-reviewed academic journal, and wait for other linguists to weigh in. Since Watson is not even a linguist, this entire line of argument is mere conjecture.

Next, Watson claims that the word "tron" is a synonym for "troy" and that the tron family of weight systems is an extension of the troy weight systems. As evidence he cites a single instance in which the Public Record Commissioners translated "troni ponderacionem" as "troy weight." The Public Record Commissioners were responsible for compiling statute books and translating old statutes from Latin and Anglo-Norman into modern English. The text in question is from the Assize of Weights and Measures (Tractatus Ponderibus et Mensuris), one of the famous Statutes of uncertain date circa 1266-1304. However, according to the OED the word "troy" in connection to weight is first attested about a century later in 1390. Furthermore, both the tron scale and the tron family of weight systems are well documented and have no connection with troy weights.

Finally, I can find no mention of this theory in the literature, or anywhere for that matter.

Then there is Watson's second theory, described in this article under Origins in the History section, that the troy system may have some connection to Arabic weights, in particular to the 48-grain dirhem (i.e., twice the troy pennyweight in the same way that the 45-grain dirhem is twice the 45-grain dirhem). Watson admits (page 6) that this is a conjecture, his own words being "it is not unreasonable to suppose that there is some connection ." I have seen the same conjecture in various 19th century Google books. Even though I find this conjecture intriguing and would like to see some real evidence to back it up, I have not been able to find any mention of it in reliable contemporary sources.

In conclusion, I feel that the inclusion of Watson's first theory violates WP:FRINGE and should be removed, while mention of the second theory should also be removed on the grounds that Watson's book is an unreliable tertiary source.

Zyxwv99 (talk) 15:22, 11 September 2012 (UTC)

 * Both ounces of 450 and 480 grains, are known in England, these are the gol s to a use of weight (as does avoirdupoise, which appears in the legislation long before the 7000-grain pound), can only refer to a use of weights, rather than a scale.

 * The english penny was widely regarded in Germany, and the 450-grain ounce followed it as the 3600-grain mark, and the 7200-grain pound of the hanseatic league.

 * More recent authors who follow these arguments are Ronald Zupko (British Weights and Measures, 1977), Henry Chisholm, (On the science of weighing and measuring the standards of weights and measures, 1877), F.G.Skinner (Weights and Measures, 1967). Chisholm was the keeper of standards in the UK, and Skinner looked after the standards at the British Museum.  Wendy.krieger (talk) 10:58, 10 May 2018 (UTC)

The above user that started this section is an idiot, citing a bunch of made up rules, pretending to not read the sources, and deleting things he does not understand,which by all accounts is a lot more interesting - and accurate, then this page -- at least now.

The book quoted is not making any "theories", unlike the theories of this anonymous wikipedia??, it is only referencing what certain well known references of that time said, including laws from many periods of England (including when the Norman french conquered it - necessary), and the English Dialect Dictionary. https://archive.org/stream/englishdialectdi06wriguoft#page/250

The user above "emotes" and ""feels"" his arguments -- I am not making this up - he says "I feel", etc. And spends the greater part of his arguments in logical fallacies of building strawmen and watching red herrings fly by, meanwhile entirely ignoring that the book cited simply cites original sources - laws at various times in England and a dictionary.

Far from being an unknown linguist, the author of the dictionary referred to was a Professor of Comparative Philology at Oxford University. https://en.wikipedia.org/wiki/Joseph_Wright_(linguist),and the work a well known, definite work of the period (not my words).

There is nothing more definite then laws showing the word was in use before the claim, and academic dictionaries stating it outright. The proper thing to do in such circumstances is to look up the primary sources quoted in the original work, and cite them in order after the original reference, not pretend they aren't quoting the other work, and go off in some weird tangent claiming quoting sources are theories, randomly deleting things.

I am not the original writer, I stumbled on this page just now and bothered to read the sources mentioned. The Wikipedia a mess as usual.. — Preceding unsigned comment added by 66.42.179.151 (talk) 17:26, 27 August 2018 (UTC)

Mint Weights
The progression of subdivisions makes the smallest, the blank, equal to about 281 nanograms. Yowza! Were these finest of units ever in common use, even by the mint? It seems hard to believe that one could conceive of weighing anything to anywhere near that precision in 1649. Joe Avins (talk) 17:05, 29 May 2013 (UTC)

 * At the time these units were developed, precision of measurement was progressing by leaps and bounds. They had no idea what kind of precision would be possible in future centuries, but they wanted to be prepared. Kind of like using 4 digits for computer dates instead of 2, or other situations where extra room is left for future possibilities. Even though the smallest mint weights were not in routine use, the standards laboratories that supervised the mints had very advanced technology (for the time) and went to extreme lengths in calibrating their own standards. Zyxwv99 (talk) 01:50, 5 June 2013 (UTC)

Not usual
Troy pounds are not usually used when referring to the weight of precious metals, even if more than 12 ounces are involved. — Preceding unsigned comment added by MissouriOzark1947 (talk • contribs) 14:40, 11 December 2014 (UTC)

Nonsensical numbers
I came to this article looking for a comparison between Troy and metric measures, as a highly educated layperson, so I could translate the “10 grams of gold flakes monthly” claim of Venezuelan miners into fractions of a Troy ounce. I’ve left the article totally confused, as a layperson, at the way numbers are presented.

Here is one example of the seemingly nonsensical way numbers are presented: “one troy ounce (oz t) equals exactly 31.103 476 8 grams.” How is one supposed to interpret the meaning of this string of nine digits that has a decimal point after the second digit, and spaces after the sixth and eighth digits, in the absense of any explanatory footnotes? It doesn’t follow any standard way of expressing a number that I am familiar with. If this presentation is in accordance with a Wikipedia number-display standard I have never seen it used elsewhere on the site despite years of almost-daily views.

There are many other places in the article where numbers are displayed in nonsensical ways or the display is inconsistent.

Can someone clean this up? I would but I don’t know the subject well enough to do so and I don’t want to destroy some standard ways of presenting the numbers (but obscure to the layperson).

Thanks for reading. — Preceding unsigned comment added by 24.113.172.196 (talk) 15:24, 10 February 2019 (UTC)

 * Those are just digit grouping spaces. The use of spaces for digit grouping has been very common for several decades in English scientific writing for international audiences. I remember being introduced to it in the early 1980s. It avoids possible confusion between decimal point and the decimal comma used in some other languages. Indefatigable (talk) 20:20, 12 February 2019 (UTC)

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Approximately (BRD discussion)
In the section Troy pound, for a long time the text has read An avoirdupois pound is approximately 21.53% heavier at 7000 grains. appears to believe that it needs greater precision and changed it to An avoirdupois pound is 21.527777$\overline{7}$% heavier at 7000 grains. I reverted with the edit note "RV good faith but for most readers, the approximation is all they need: for anyone for whom it matters, assume that they can do the maths.

Eric counter-reverted, this time with An avoirdupois pound is approximately 21.52778% heavier at 7000 grains. [This is a new concept of 'approximate': going to five decimal places rather than two yields a difference from the original approximation of less than 13 gr.]

Although the amount involved is trivial, the real argument to me is wp:think of the reader. We should not annoy the reader with pettifogging detail, indeed IMO if the text needs changing, it should say approximately 22.5%. So I am reverting again per WP:BRD and invite comment from other editors to see if we can reach a consensus. --John Maynard Friedman (talk) 20:10, 16 December 2021 (UTC)
 * I agree, 4 significant figures is pleanty. Anyone who needs more precision can use the grain values and do the math. Jc3s5h (talk) 21:12, 16 December 2021 (UTC)

 * The reason I put that is that it shows that the conversion factor has repeating sevens, due to the fact that 5760 equals 2$7$3$2$5. For those with a mathematical inclination, this is an interesting fact. I really don't think it's worth arguing about. Eric Kvaalen (talk) 15:08, 17 December 2021 (UTC)

Problems with Dutch (language mainly)
Referring to the section ‘Dutch system’, the 20th part of the ounce (whether troy, market or weigh-house) was in Dutch called engels, in the singular, the plural was engelsen. (Engels litterally means ‘English’, as it was inspired by the English pennyweight. The French name for the 20th of an oune was esterlin, which is likewise etymologically related to ‘(penny) sterling’.)

The 32nd part of the engels was in Dutch called aas in the singular, plural azen. In Dutch as can only mean ‘axle’ or ‘ash’ (of a fire, not the tree). Exceptionally, as can mean the Roman weight or coin.

The so-called Holland troy weight (“Hollandsch Trooisch Gewicht”) used a pound of 2 troy marks or 16 troy ounces, instead of the 12 ounces usual elsewhere.

Amsterdam weigh-house weight {“Amsterdamsch Waag-gewicht”) was 40 ´´azen´´ heavier to the pound than Holland troy weight.

I have not changed anything in the article, mainly because I do not have my sources (mainly the book on old Dutch weights, Oude Nederlandse Gewichten by Zevenboom and Wittop Koning, and the Grote Winkler Prins Encyclopedie, 1972–75 edition) readily available to cite at present. — Mithrennaith (talk) 05:37, 18 April 2022 (UTC)

Troy from Troyes - remove 'probable'
The several references to Troy weight 'probably' deriving from Troyes rather ignores the comprehensive work in wiki-France which adds considerable detail to the certainty of the Troyes markets being a valid origin. The 1910 efforts by Watson to suggest 'tron' or an Arabian origin do not seem to have valid weight (! pun). I think despite the entertainment derived from his philological research that historical detail (as per wiki-France) should require his deletion from here and the removal of 'probably' from the source being Troyes. Nojoking (talk) 06:34, 27 October 2022 (UTC)
 * Sources in another Wikipedia article, such as the one at the French Wikipedia, don't count unless they are cited in this article. So someone would have to figure out which article Nojoking is referring to, identify which sources support the claim, gain access to the sources, read them, and decide if they really do support the claim. Jc3s5h (talk) 16:34, 27 October 2022 (UTC)

capitalization of "Troy"
Both capitalized and lower-case "t" in "Troy" are used here. Is there an agreed-upon way to style this? troy ounce or Troy ounce? -MJ (talk) 03:34, 9 March 2024 (UTC)

title: Talk:Troy weight


text:
Mario Andretti

Mario Gabriele Andretti (born February 28, 1940) is an Italian-born American former racing driver. He is widely regarded among the most successful drivers in the history of motorsports. Andretti is one of only three drivers to have won races in Formula One, IndyCar, the World Sportscar Championship, and NASCAR. He has also won races in midget car racing and sprint car racing.

Andretti won the Formula One World Championship in 1978, four IndyCar titles, including three under USAC sanctioning, and one in CART. He is the only driver to win the Indianapolis 500 (1969), Daytona 500 (1967) and the Formula One World Championship, and, along with Juan Pablo Montoya, the only driver to have won a race in the NASCAR Cup Series, Formula One, and an Indianapolis 500. As of 2023, Andretti's victory at the 1978 Dutch Grand Prix is the most recent Formula One win by an American driver. Andretti had 109 career wins on major circuits.

Andretti is the only person to be named United States Driver of the Year in three decades (1967, 1978, and 1984). He was also one of only three drivers to have won major races on road courses, paved ovals, and dirt tracks in one season, a feat that he accomplished four times. With his final IndyCar win in April 1993, Andretti became the first driver to have won IndyCar races in four different decades and the first to win automobile races of any kind in five.

In American popular culture, Andretti's name has become synonymous with speed ("You think you're Mario Andretti?"), similar to Barney Oldfield in the early 20th century and Stirling Moss in the United Kingdom.

Early life
Andretti and his twin brother Aldo were born to Alvise Andretti, a farm administrator, and his wife, Rina, in Montona, Istria, Kingdom of Italy, in present-day Motovun, Croatia. Istria was then part of the Kingdom of Italy, but it became part of Yugoslavia at the end of World War II as product of the Treaty of Paris in 1947 and later the Treaty of Osimo in 1975. In 1948, the Andretti family, like many other Istrian Italians at the time, left during the Istrian–Dalmatian exodus. They initially ended up in a refugee camp in Lucca, Italy.

In 2013, Andretti told author Paul Stenning, "My father left everything behind, we left our home and took what we could carry and went further into Italy. They had to swallow all of these families that were dispersed and they formed all different camps over Italy and we were shipped to a place in Tuscany. Life was a bit weird at the time but the one thing that my father always did, he always provided for us. As kids we were never cold, we were never hungry, we went to school, he always provided quite well."

Childhood involvement in motorsports
The twins' mother Rina said that when they were two years old, they would take pot lids out of the cupboards and run around the kitchen, going "Vroom, vroom," like they were driving cars before the twins had even yet seen a car. In 1945, at age five, he and Aldo were racing their hand-crafted wooden cars through the steep streets of their hometown. The brothers were later hired by a garage to park cars. In his autobiography, What's It Like Out There, published in 1970, Andretti described the experience, writing, "The first time I fired up a car, felt the engine shudder and the wheel come to life in my hands, I was hooked. It was a feeling I can't describe. I still get it every time I get into a race car."

Andretti's first racing experience was in a new youth racing league called Formula Junior in Ancona, Italy, when he was thirteen years old. Years later, in an interview during an RRDC Evening with Mario Andretti, Andretti implied that he and his brother made up the story of racing in the Formula Junior league when they moved to Pennsylvania to improve their chances of competing in dirt track racing because, having purchased racing suits in Italy, they looked the part.

Marco De Cesari and Danilo Piccinini, the owners of the garage, noticed the Andretti brothers' passion for racing and brought them to the Abetone pass to watch a stretch of the Mille Miglia race in 1954 which caused him to become captivated by Italian two-time Formula One world champion Alberto Ascari, who won the race. Later in the same year, Piccinini brought the brothers to the Monza for the Italian Grand Prix, where Andretti saw Ascari and Juan Manuel Fangio race against each other. "I remember being just mesmerized, overwhelmed by the sound, by the speed" Andretti recalled years later. "We didn't even have a grandstand seat, we were up on that bank before the Parabolica on the left. You know, we had a good view of things ".

Move to the U.S. and start in racing
Andretti's father had maintained contact with his brother-in-law who had lived in the U.S. for many years. It took the family three years to obtain a U.S. visa. Alvise Andretti initially told the family they would move to the U.S. for five years and then return to Italy. In 1955, the Andretti family emigrated to the U.S., settling in Nazareth in the Lehigh Valley region of eastern Pennsylvania with just $125 to their name.

In 2013, Andretti said, "When I looked at my life in many ways out of so many negatives here comes a positive and this was certainly one of them, here was an opportunity created for us, the kids, and my dad always cited that. He would say in a sense I am looking at your future, where I think would be the best solution for you kids to have opportunities and he was correct, he was right because if we had remained in Italy I don't know whether I could have pursued what my first passion was and the only passion I really had career wise."

While getting acquainted with Pennsylvania, Mario and Aldo were surprised to find a half-mile dirt racing track Nazareth Speedway in Nazareth. The twins worked on a 1948 Hudson and raced it in the Limited Sportsman Class, funded by money that they earned in their uncle's garage in 1959. They took turns racing the old Hudson on oval dirt tracks near Nazareth. After finishing high school, Mario planned to become a welder, but he falsified a driver license so he could pass for 21 and enter an amateur race. Mario and Aldo did not tell their parents that they were racing. The twins each had two wins after their first four races. Aldo was seriously hurt near the end of the season, and their parents were unhappy to find out that the twins were racing. Mario had 21 modified stock car wins in 46 races in 1960 and 1961.

USAC stock car
Andretti became a naturalized U.S. citizen in 1964. He competed in United States Auto Club (USAC) stock car events in 1965, and finished twelfth in the season points. He won a USAC Stock Car race in 1967, and finished seventh in the season points. He won three 1974 USAC stock car races on road courses, and won four road course races in 1975.

NASCAR
Andretti competed in fourteen NASCAR Grand National/Winston Cup (now NASCAR Cup Series) events in his career. He competed in Holman Moody cars for his final ten events. Holman Moody was one of NASCAR's most successful teams at that time, as the team won NASCAR championships in 1968 and 1969 with driver David Pearson. Andretti won the 1967 Daytona 500 for Holman Moody.

International Race of Champions
Andretti was invited to race in six International Race of Champions (IROC) series in his career. His best years were his first three years. He finished second in the final points standings in IROC III (1975–1976) and IROC V (1977–1978). He won the IROC VI (1978–1979) points championship with finishes of third, first, and second. He won three races in twenty events.

Early open-wheel racing
Andretti's goal was to race in single-seater open-wheel cars. Andretti said "Aldo and I were winning in the modifieds. But my objective was to get into open-wheelers."

Andretti raced midget cars from 1961 to 1963. He started racing 3/4 (sized) midget cars in the American Three Quarter Midget Racing Association in the winter to be seen by full-sized midget car owners. He raced in over one hundred events in 1963. Andretti won three feature races at two different tracks on Labor Day in 1963. He won an afternoon feature at Flemington, New Jersey, and swept twin features at Hatfield, Pennsylvania.

The next rung on the racing ladder on the East Coast of the United States was to race in sprint cars in the United Racing Club (URC). Andretti was able to get a ride for individual races in the URC sprint car racing series, but was unable to secure a full-time ride. He once drove from Canada to Mechanicsburg, Pennsylvania hoping to find a ride in an event, but he went empty-handed. He bypassed the series when he was offered a full-time ride in a United States Automobile Club sprint car for 1964.

USAC sprint cars
Andretti won the 1964 Joe James-Pat O'Connor Memorial USAC sprint car race at Salem Speedway in Salem, Indiana. Andretti continued to race in USAC sprint cars after moving into champ cars. In 1965 he won once at Ascot Park, and finished tenth in the season points. In 1966 he won five times (Cumberland, Maryland, Oswego, New York, Rossburg, Ohio, Phoenix, Arizona, and his second win at the Joe James-Pat O'Connor Memorial at Salem Speedway), but finished behind Roger McCluskey in the season championship. In 1967 he won two of the three events that he entered.

IndyCar career (1964–1974)
From 1956 to 1979, the top open-wheel racing series in North America was the USAC National Championship. It was often referred to as IndyCar racing, referring to the famous Indianapolis 500 race which was the centerpiece of the championship. The races were run on a mixture of paved and dirt ovals, and in later years also included some road courses.

Andretti made his IndyCar debut on April 19, 1964, at the New Jersey State fairgrounds in Trenton, New Jersey. He started sixteenth and finished eleventh. Andretti was introduced by his USAC sprint car owner, Rufus Gray, to veteran mechanic Clint Brawner. Brawner was not impressed since sprint car drivers Stan Bowman and Donnie Davis had recently died, and Brawner's current driver, Chuck Hulse, had been critically injured. Chris Economaki recommended Andretti to Brawner, so Brawner watched Andretti race at Terre Haute, Indiana. Brawner was convinced that he had found the new driver for his team. The two stayed together for six years. Andretti finished eleventh in the USAC National Championship that season. Andretti won his first championship car race at the Hoosier Grand Prix on a road course at Indianapolis Raceway Park in 1965. His third-place finish at the 1965 Indianapolis 500 in the Brawner Hawk (a mechanical copy of the then-current Brabham Formula 1 design) earned him the race's Rookie of the Year award, and contributed towards Andretti winning the series championship. He was the youngest national champion in series history at age 25. He repeated as series champion in 1966, winning eight of fifteen events. He led every lap of the 1966 Langhorne 100. He also won the pole at the 1966 Indianapolis 500. Andretti finished second in IndyCar in 1967 and 1968. He also won a single non-championship drag race in 1967 in a Ford Mustang. In both 1967 and 1968, Andretti lost the season USAC championship to A. J. Foyt and Bobby Unser, respectively, in the waning laps of the last race of the season at Riverside, California—each by the smallest points margin in history.

Andretti won nine races in 1969, the 1969 Indianapolis 500, and the season championship. He also won the Pikes Peak International Hill Climb, which was part of the USAC National Championship. He was named ABC's Wide World of Sports Athlete of the Year. Between 1966 and 1969 he won 29 of 85 USAC championship races.

In 1973, USAC split its National Championship into dirt and pavement championships. Andretti had one win on the pavement and finished fifth in the season points, and finished second in the dirt championship. He competed in USAC's dirt track division in 1974, and won the dirt track championship while competing in both series. Andretti also competed in the North American Formula 5000 series in 1973 and 1974, and finished second in the championship in both seasons.

Part-time status (1968–1972, 1974)
Formula One is the highest form of open-wheel racing sanctioned by the Fédération Internationale de l'Automobile (FIA), motorsport's international governing body. Although originating in Europe, by the 1960s it included races worldwide. At Andretti's first Indianapolis 500, in 1965, he met Colin Chapman, owner of the Lotus Formula One team, who was running eventual race winner Jim Clark's car. Andretti told Chapman of his ambition to compete in Formula One and was told "When you're ready, call me." By 1968 Andretti felt he was ready. Chapman gave him a car, and the young American took the pole position on his debut at the 1968 United States Grand Prix at Watkins Glen in his Lotus 49.

Andretti drove sporadically in Formula One over the next four years for Lotus, March, and Ferrari, while continuing to focus on his racing career in America. At the 1971 South African Grand Prix, on his debut for Ferrari, he won his first Grand Prix. "That was a big moment, one of those I'll always cherish," recalled Andretti. "Kyalami was a fun circuit to drive with lots of elevation changes and Ferrari gave me equal equipment to my teammates. It was a good weekend." Three weeks later, at the non-championship Questor Grand Prix in the U.S., he brought the Italian team a second victory. The day before the Questor GP, he had finished 9th in the Indy car race at Phoenix International Raceway. At the end of the season, Ferrari called Andretti and made him a pitch to be his No. 1 driver but Andretti declined. "F1 didn't pay much back then and my contracts and commitments were so lucrative over here I couldn't give that up for the security of my family. The timing wasn't right yet, so I had to turn him down; but I always figured I'd get another opportunity."

Full-time status (1975–1981)
In 1975 Andretti drove a full Formula One season for the first time, for the American Parnelli team. The team was new to Formula One, although it had been successful in both Formula 5000 and IndyCar racing in America with Andretti driving. The team had run Andretti in the two North American end-of-season races in 1974 with promising results. Andretti qualified fourth and led the 1975 Spanish Grand Prix for nine laps before his suspension failed. He scored five championship points in the season. Andretti continued to compete in IndyCar, missing two Formula One races in the middle of the season to do so. When the Parnelli team pulled out of Formula One after two races of the 1976 season, Andretti returned to Chapman's Lotus team, for whom he had already driven at the season-opening Brazilian Grand Prix. Lotus was then at a low point, having failed to produce a competitive car to replace 1970's Lotus 72. Andretti's ability at developing a racing car contributed to Lotus' return to the front of the Formula One grid, culminating in lapping the field in his victory at the season ending race at the Mount Fuji circuit in Japan. Since mid-1975 Lotus had been developing the use of ground effect, shaping the underside of the car to generate downforce with little penalizing drag. For his part, Andretti worked at setting up his cars for the races, exploiting subtle differences in tire size ('stagger') and suspension set up ('cross weighting') on each side of the car to optimize it for each track, an approach imported from his extensive oval racing experience in the United States. In 1977, at Long Beach, he became the only American to win the United States Grand Prix West, and the last American as of 2022 to win any US Grand Prix. The Lotus 78 "wing car" proved to be the most competitive car of 1977, but despite winning four races, more than any other driver, reliability problems and collisions with other drivers meant Andretti finished only third in the championship.

At the end of 1977, Andretti was approached by Ferrari as a potential replacement for Niki Lauda. "I had a handshake agreement with Colin and he'd already agreed to pay me what Ronnie Peterson was making, which was the highest salary in F1. So I asked Mr. Ferrari what was he willing to pay me. He said, 'You know, Mario, I can't put a price on your talent so you tell me.' That SOB threw it right back in my lap! Well, [Andretti's wife] Dee Ann was sitting next to me and I asked her what should I do and she said 'double it.' And Mr. Ferrari agreed. The next day I got a telex from him saying 'Let's just leave things alone' because he'd just had a visit from Colin (who'd) followed me to Maranello and raised hell with Mr. Ferrari. Can you imagine? So I told Colin he'd always been good to me but you don't want an unhappy driver. Then I told him I wanted $10,000 a point — you got nine points for a win back then — and he had to agree.'

In 1978, the Lotus 79 designed by Chapman exploited ground effect even further. Andretti dominated the season and took the title with six wins. He clinched the championship at the Italian Grand Prix. There was no championship celebration though because his teammate Ronnie Peterson crashed heavily at the start of the race; he was hospitalised and died that night from complications resulting from his injuries.

Andretti found little success after 1978 in Formula One – he failed to win another grand prix. He had a difficult year in 1979, as the new Lotus 80 was not competitive, and the team had to rely on the Lotus 79 which had been overtaken by the second generation of ground effect cars. In 1980, he was paired with the young Italian Elio de Angelis, and briefly with test driver Nigel Mansell, but the team was again unsuccessful.

For the 1981 season, Andretti decided to move to the Alfa Romeo team run by Carlo Chiti. Although the car was reasonably competitive (Andretti finished fourth on his debut with the team in Long Beach), a general lack of reliability resulted in yet another unsuccessful campaign. Like other drivers of the period, Andretti did not like the ground effect cars of the time: "the cars were getting absurd, really crude, with no suspension movement whatever. It was toggle switch driving with no need for any kind of delicacy...it made leaving Formula One a lot easier than it would have been."

Brief returns with Williams and Ferrari (1982)
The next year, Andretti raced once for the Williams team, after their driver Carlos Reutemann suddenly quit, before replacing the seriously injured Didier Pironi at Ferrari for the last two races of the year. Suspension failure dropped him out of the last race of the season, but at the Italian Grand Prix at Monza he took the pole position and finished third in the race.

There was almost a return to F1 for Andretti at the 1984 Detroit Grand Prix when the Renault team put him on standby to replace regular driver Patrick Tambay if the Frenchman had been unable to race, as was the case at the previous race in Canada. However, in the event, Tambay was able to take part in the race.

Andretti was also considered as a replacement, again for Tambay who had been injured in Canada, at the 1986 Detroit Grand Prix, this time for the Carl Haas-owned Haas Lola team. Andretti declined, but recommended his son Michael Andretti. When Michael was unable to obtain the FIA Superlicense required to allow him to race in Formula One, the drive went to Eddie Cheever.

Return to IndyCar racing (1982–1994)

Andretti had continued to race, and occasionally win, in the USAC National Championship during his time in the Formula One world championship. In 1979 a new organization, Championship Auto Racing Teams (CART), had set up the IndyCar World Series as a rival to the USAC National Championships that Andretti had won three times in the 1960s. The new series had rapidly become the top open-wheel racing series in North America.

Andretti joined CART full-time in 1982, driving for Patrick Racing. He started from row two in the Indianapolis 500 that year but was involved in a wreck on the approach to the start when rookie Kevin Cogan suddenly spun out. Three minutes after the wreck Andretti was heard saying "This is what happens when you have children doing a man's job up front," and he and Cogan were later involved in a shoving match.

In 1983, he joined the new Newman/Haas Racing team, set up by Carl Haas and actor Paul Newman using cars built by British company Lola. Andretti took the team's first win at Elkhart Lake in 1983. He won the pole for nine of sixteen events in 1984, and claimed his fourth Champ Car title at the age of 44. He edged out Tom Sneva by 13 points. It was the first series title for the second year team.

In August 1986, Andretti won the Pocono 500, in his 14th attempt to win at the track near his Pennsylvania home. It gave Andretti 500-mile Indy car wins at Indianapolis, Michigan, and Pocono.

Mario's son Michael joined Newman/Haas in 1989. Together, they made history as the first father/son team to compete in both IMSA GT and Champ Car racing. With regard to the former, it was their fourth time in an endurance race together as co-drivers. Mario finished seventh in points for the 1991 season, the year that Michael won the championship. Mario's last victory in IndyCar racing came in 1993 at Phoenix International Raceway, the year that Michael left Newman/Haas to race in Formula One. The win made Mario the oldest recorded winner in an IndyCar event (53 years, 34 days old). Andretti qualified on the pole at the Michigan 500 later that year with a speed of 234.275 mph. The speed was a new closed course world record. Andretti's final season, in 1994, was dubbed "The Arrivederci Tour". He raced in the last of his 407 Indy car races that September.

Indianapolis 500
Andretti won once at the Indianapolis 500 in 29 attempts. Andretti has had so many incidents and near victories at the track that critics have dubbed the family's performance after Mario's 1969 Indianapolis 500 victory the "Andretti Curse".

Andretti finished all 500 mi just five times, including his 1969 Indianapolis 500 victory. Andretti was the first driver to exceed 200 mi/h while practicing for the 1977 Indianapolis 500. In 1969, after 4 years of bad luck and 4 non-finishes, Andretti dominated the Indianapolis 500 en route to his only victory in the race. The race is notable as it is the only Indy 500 in history where the winning driver ran the whole race on only 1 set of tires.

Between his 1969 victory in the race and 1981, Andretti dropped out of the races due to part failures or crashes. His luck seemed to turn around in 1981. Andretti finished second in the 1981 Indianapolis 500 by eight seconds behind Bobby Unser. The following day Unser was penalized one lap for passing cars under a caution flag, and Andretti was declared the winner. Unser and his car owner Roger Penske appealed the race stewards' decision. USAC overturned the one lap penalty four months later, and penalized Unser with a $40,000 fine.

At the start of the 1982 Indianapolis 500, second-year driver Kevin Cogan, teammate to polesitter Rick Mears, suddenly spun right when accelerating for the green flag. Cogan bounced off A. J. Foyt, slamming Foyt's steering rod. That contact turned Cogan's car left at a 90-degree angle to the field, where he was promptly T-boned by Mario. Andretti was livid and engaged in a shoving match with Cogan before walking off. In an interview, three minutes after the wreck, an irked Andretti was heard saying "This is what happens when you have children doing a man's job up front." Andretti's Patrick Racing teammate that year was the eventual race winner, Gordon Johncock, who started next to Andretti in the middle of row two. In later years, Johncock pointed out that Andretti had jumped the start, and could have avoided the spinning car of Cogan had he been lined up properly in the second row next to Gordy.

In the 1985 Indianapolis 500, he was passed for the lead by Danny Sullivan in Turn One on lap 20. Immediately after completing the pass, Sullivan spun in front of Andretti. A caution flag for the spin minimized the time Sullivan would lose to Andretti by pitting to replace his tires. Sullivan took the lead for good 20 laps later when he passed Andretti without incident. Andretti dominated the 1987 Indianapolis 500, leading 170 of the first 177 laps of the race. His lead was so large, that he was advised to slow his pace to preserve his equipment. In a cruel twist of fate, when Andretti started running slower, his reduced engine rpm's created a harmonic imbalance in his turbocharged Ilmor/Chevrolet V8 that led to a broken valve spring with 20 laps to go.

The 1992 Indianapolis 500 was run in extremely cold weather which resulted in a large number of wrecks by cars on cold tires. Andretti accelerated off of turn three for the restart at the end of the 83rd lap. Under acceleration, Mario's car got loose in the middle of turn four and rotated 270 degrees to smash nose first into the wall. Andretti was taken to the hospital with six of his toes broken and would shortly be joined by his son Jeff Andretti who smashed both legs after a wheel came loose on his race car on the 109th lap of the race. Mario would only miss one race due to his injuries, and returned to run 6th in a race just four weeks after his crash.

The 1993 Indianapolis 500 was Andretti's last notable run, and he had just come off a victory at Phoenix. On pole day, Andretti was the first car to complete a qualifying run, and sat on the provisional pole position. Andretti's speed held up all afternoon, but with less than an hour to go, Arie Luyendyk topped his speed, and took the pole. On race day, Andretti was a factor most of the afternoon, leading the most laps (72). While leading on lap 134, Andretti was penalized for entering the pits while they were closed. A stop-and-go penalty dropped him only down to second place. In the final 50 laps, he began developing handling problems because of his tires, and slid down the standings to finish 5th. Andretti's last race at Indy was the 1994 Indianapolis 500.

On April 23, 2003, in the lead up to the 2003 Indianapolis 500, Andretti took to the track for the first time in ten years in a major open-wheel car at the age of 63. He participated in a test session for son Michael's AGR IndyCar team. One of the team's regular drivers, Tony Kanaan, suffered a radial fracture of his arm a week earlier in an April 15 crash at Twin Ring Motegi. If Kanaan was not cleared to drive in enough time, tentative plans were being prepared for Andretti to qualify the car for him. He would turn the car over to Kanaan on race day, though no plans had been made for Andretti to actually drive in the race. During the test, Andretti ran at competitive speeds, but running over debris saw his car becoming airborne and the attempt ended with a spectacular crash. Andretti was able to walk away from the wreck with just a minor cut on his chin. This was Andretti's last significant on-track activity at Indianapolis.

Sports cars
His first race start with a Ferrari was in 1965 with a Ferrari 275 P during the Bridgehampton 500 km at Bridgehampton Race Circuit; he did not finish the race. Andretti won three 12 Hours of Sebring endurance races (1967, 1970, 1972), and a 6-hour race at Daytona in 1972. In early sportscar races he competed for the Holman Moody team, but later often drove for Ferrari. He signed with Ferrari in 1971, and won several races with co-driver Jacky Ickx. In 1972 he shared wins in the three North American rounds of the championship and at Brands Hatch in the UK, contributing to Ferrari's dominant victory in that year's World Championship for Makes. He also competed in the popular North American Can-Am series in the late 1960s and early 1970s.

Le Mans
Andretti competed at the 24 Hours of Le Mans in four decades. In 1966 he shared a Holman Moody Ford Mk II with Lucien Bianchi. They retired after their car dropped a valve at 10:30 pm. In 1967, during a 3:30 am pit stop, a mechanic inadvertently installed a front brake pad backward on his Ford MkIV. As Andretti passed under the Dunlop Bridge before the Esses, he touched his brake pedal for the first time since leaving the pits. The front wheel instantly locked, turning the car hard into the dirt embankment at 150 mi/h. The wreckage slid to a stop with Andretti badly shaken, the car sideways to oncoming traffic and the track nearly blocked. His teammates, Jo Schlesser and Roger McCluskey, crashed trying to avoid Andretti's car. McCluskey pulled Andretti to safety, and Andretti was taken to hospital for x-rays.

Andretti did not return to Le Mans until his full-time Formula One career was over. In 1982, he partnered with son Michael in a Mirage M12 Ford. They qualified in ninth place, but the pair found their car being removed from the starting grid 80 minutes before the start of the race, as an official discovered an oil cooler that was mounted behind the gearbox, which was against the rules. The car had passed initial inspection four days before the race. Despite protests and complaints, Andretti's entry was removed altogether, replaced by a Porsche 924 Carrera GTR. Their return in the following year was more successful as they finished third. The father/son team returned in with Mario's nephew John. They finished sixth in a factory Porsche 962. Following Mario's retirement from full-time racing, he decided on a return to the circuit to add a Le Mans victory to his achievements. He returned in with a second-place finish. He said in a 2006 interview that he feels that the Courage Compétition team "lost [the 1995] race five times over" through poor organization. He had unsuccessful efforts in the following years with a thirteenth place in, and then a DNF (Did Not Finish) for. Andretti's final appearance at Le Mans was at the 2000 race, six years after his retirement from full-time racing, when he drove the Panoz LMP-1 Roadster-S at the age of 60, finishing 15th.

Awards and honors
In 1986, he was inducted into the Indianapolis Motor Speedway Hall of Fame. In 2000, the Associated Press and RACER magazine named him Driver of the Century. He was the Driver of the Year (in the United States) for three years (1967, 1978, and 1984), and is the only driver to be Driver of the Year in three decades. Andretti was named the U.S. Driver of the Quarter Century in 1992. He was inducted into the International Motorsports Hall of Fame in 2001, the United States National Sprint Car Hall of Fame in 1996, the Motorsports Hall of Fame of America in 1990, the Hoosier Auto Racing Hall of Fame in 1970, the Automotive Hall of Fame in 2005, and the Diecast Hall of Fame in 2012.

On October 23, 2006, Andretti was awarded the highest civilian honor given by the Italian government, the Commendatore dell'Ordine al Merito della Repubblica Italiana (known as the Commendatore), in honor of his racing career, public service, and enduring commitment to his Italian heritage. In 2007, Andretti was honored with the "Lombardi Award of Excellence" from the Vince Lombardi Cancer Foundation for making "a "Hall of Fame" contribution to a sport, profession, or business in a manner that exemplifies appreciation of God, country, society, family and self." That same year, he was also named the "Mayor" (Sindaco) of the "Free Commune of Motovun in Exile" (Libero Comune di Montona in esilio), an association of Italian exiles from Motovun. In 2008, Andretti was awarded with the Simeone Foundation Spirit of Competition Award.

In 2016, Andretti was made an honorary citizen of Lucca. In 2019, the city of Indianapolis renamed a street "Mario Andretti Drive", as part of the celebrations of the 50th anniversary of his first Indianapolis 500 win.

Mario Andretti Grand Prix of Road America
Mario was instrumental in keeping championship car racing at Road America in Elkhart Lake, Wisconsin. The Champ Car World Series severed its ties with the track as a legal resolution of payment issues from the 2002 and 2003 series events at the track. Andretti was the middle man between CART President Chris Pook and Road America President George Bruggenthies. After six weeks both sides came to terms and signed a two-year contract. The event was renamed the "Mario Andretti Grand Prix of Road America".

Elder of Andretti racing family
Both of Mario Andretti's sons, Michael and Jeff, were auto racers. Michael followed in his father's footsteps by winning the IndyCar title, with Mario's nephew John Andretti joining the series in 1988. This meant that the Andrettis became the first family to have four relatives compete in the same series. With Mario sharing driving duties with sons Michael and Jeff at the 1991 Rolex 24 at Daytona, driving a Porsche 962, the Andretti clan finished 5th.

Mario's grandson Marco completed his first full season in the Indy Racing League (IRL) in 2006, driving for his father Michael's Andretti Green Racing team. Marco finished second in the 2006 Indianapolis 500 and so became the first third-generation recipient of the race's Rookie of the Year Award.

Later life
Andretti lives near his grandson Marco in Bushkill Township, Pennsylvania. His late wife Dee Ann (née Hoch) was a native of Nazareth, Pennsylvania, who taught Andretti English in 1961. They were married on November 25, 1961. She died on July 2, 2018, following a heart attack.

Andretti has remained active after his retirement from full-time racing, making numerous speaking engagements to audiences and serving as a spokesman for Texaco/Havoline, Firestone, and Magnaflow performance exhaust. He was occasionally a spokesman for the now defunct Champ Car World Series, though he frequently attended IRL races to watch Marco compete. Andretti is vice chairman of a winery named Andretti Winery in Napa Valley, California. He owns a chain of gasoline stations, a Toyota dealership in Moon Township, Pennsylvania (just outside Pittsburgh), car washes, car-care products, go-kart tracks, a clothing line, video games and replica cars. He also test drives cars for Road & Track and Car and Driver magazines.

In 2006, he was named by Carnegie Corporation to the inaugural class of winners of the Great Immigrants Award.

In July 2006, Andretti took part in the Bullrun race across the United States. The first pitstop was at the Pocono Raceway in Andretti's home state of Pennsylvania with Gate No. 5 aptly named Andretti Road.

Since 2012, Andretti has been the official ambassador for the Circuit of the Americas (COTA) and the United States Grand Prix promoting awareness of Formula 1 in the United States and all forms of motorsports at COTA.

In 2015, he received the America Award from the Italy–USA Foundation.

Film and television appearances
Andretti played himself on three episodes of the United States television show Home Improvement. Along with his son Michael, he appeared in the 1996 IMAX film Super Speedway, which details the process of rebuilding one of his past cars. He is a major character and sometime narrator of the 1972 film The Speed Merchants. In the 2006 Pixar Animation Studios film Cars, Andretti makes a cameo appearance as himself, but because all of the characters in the film are sentient cars, his appearance is that of the Ford Fairlane in which he won the 1967 Daytona 500. He later had another voice role in the 2013 DreamWorks Animation film Turbo, as the traffic director at Indianapolis Motor Speedway.

Andretti appeared in the Sylvester Stallone film Driven in a cameo. He served as the grand marshal of the 2004 Baja 1000 off-road race, as seen in the documentary film Dust to Glory. Andretti was featured in the 2007 documentary A State of Vine, where he commented on his winemaking activities. In November 2015, he guest starred on an episode of Jay Leno's Garage, driving Leno in multiple fast cars and talking about his racing career.

Andretti wrote a column for the Indianapolis Star, where he wrote about other drivers, equipment and cars.

American open-wheel racing
(key) ( Races in bold indicate pole position )

Andretti Racing Enterprises IndyCar wins
These are the wins of Andretti Racing Enterprises, the team headed by legendary mechanic Clint Brawner. Andretti Racing Enterprises (the former Dean Van Lines team) was formed after Al Dean's death in 1967 and was financed during the 1968 season by Firestone.

NASCAR
(key) ( Bold – Pole position awarded by qualifying time. Italics – Pole position earned by points standings or practice time. * – Most laps led. )

Complete Formula One World Championship results
(key) (Races in bold indicate pole position; races in italics indicate fastest lap)

Complete Formula One Non-Championship results
(key) (Races in bold indicate pole position; races in italics indicate fastest lap)

Other race results

 * 12 hours of Sebring, 1st: 1967,1970,1972
 * 1000 km of Brands Hatch, 1st: 1972
 * 1000 km of Monza, 1st: 1974
 * Pikes Peak International Hill Climb, 1st: 1969
 * 6 Hours of Daytona, 1st: 1972
 * 6 Hours of Watkins Glen, 1st: 1972

Autobiographies

 * What's It Like Out There, Mario Andretti and Bob Collins. Henry Regnery Company, 1970. ISBN 978-0-8092-9672-9.
 * Mario Andretti: World Champion, Mario Andretti and Nigel Roebuck. Hamlyn, 1979. ISBN 978-0-600-39469-3.
 * Andretti, Mario Andretti. HarperCollins, 1994. ISBN 978-0-00-638302-4.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Mario Andretti


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Computational neuroscience

Computational neuroscience (also known as theoretical neuroscience or mathematical neuroscience) is a branch of neuroscience which employs mathematics, computer science, theoretical analysis and abstractions of the brain to understand the principles that govern the development, structure, physiology and cognitive abilities of the nervous system.

Computational neuroscience employs computational simulations to validate and solve mathematical models, and so can be seen as a sub-field of theoretical neuroscience; however, the two fields are often synonymous. The term mathematical neuroscience is also used sometimes, to stress the quantitative nature of the field.

Computational neuroscience focuses on the description of biologically plausible neurons (and neural systems) and their physiology and dynamics, and it is therefore not directly concerned with biologically unrealistic models used in connectionism, control theory, cybernetics, quantitative psychology, machine learning, artificial neural networks, artificial intelligence and computational learning theory; although mutual inspiration exists and sometimes there is no strict limit between fields,  with model abstraction in computational neuroscience depending on research scope and the granularity at which biological entities are analyzed.

Models in theoretical neuroscience are aimed at capturing the essential features of the biological system at multiple spatial-temporal scales, from membrane currents, and chemical coupling via network oscillations, columnar and topographic architecture, nuclei, all the way up to psychological faculties like memory, learning and behavior. These computational models frame hypotheses that can be directly tested by biological or psychological experiments.

History
The term 'computational neuroscience' was introduced by Eric L. Schwartz, who organized a conference, held in 1985 in Carmel, California, at the request of the Systems Development Foundation to provide a summary of the current status of a field which until that point was referred to by a variety of names, such as neural modeling, brain theory and neural networks. The proceedings of this definitional meeting were published in 1990 as the book Computational Neuroscience. The first of the annual open international meetings focused on Computational Neuroscience was organized by James M. Bower and John Miller in San Francisco, California in 1989. The first graduate educational program in computational neuroscience was organized as the Computational and Neural Systems Ph.D. program at the California Institute of Technology in 1985.

The early historical roots of the field can be traced to the work of people including Louis Lapicque, Hodgkin & Huxley, Hubel and Wiesel, and David Marr. Lapicque introduced the integrate and fire model of the neuron in a seminal article published in 1907, a model still popular for artificial neural networks studies because of its simplicity (see a recent review ).

About 40 years later, Hodgkin and Huxley developed the voltage clamp and created the first biophysical model of the action potential. Hubel and Wiesel discovered that neurons in the primary visual cortex, the first cortical area to process information coming from the retina, have oriented receptive fields and are organized in columns. David Marr's work focused on the interactions between neurons, suggesting computational approaches to the study of how functional groups of neurons within the hippocampus and neocortex interact, store, process, and transmit information. Computational modeling of biophysically realistic neurons and dendrites began with the work of Wilfrid Rall, with the first multicompartmental model using cable theory.

Major topics
Research in computational neuroscience can be roughly categorized into several lines of inquiry. Most computational neuroscientists collaborate closely with experimentalists in analyzing novel data and synthesizing new models of biological phenomena.

Single-neuron modeling
Even a single neuron has complex biophysical characteristics and can perform computations (e.g. ). Hodgkin and Huxley's original model only employed two voltage-sensitive currents (Voltage sensitive ion channels are glycoprotein molecules which extend through the lipid bilayer, allowing ions to traverse under certain conditions through the axolemma), the fast-acting sodium and the inward-rectifying potassium. Though successful in predicting the timing and qualitative features of the action potential, it nevertheless failed to predict a number of important features such as adaptation and shunting. Scientists now believe that there are a wide variety of voltage-sensitive currents, and the implications of the differing dynamics, modulations, and sensitivity of these currents is an important topic of computational neuroscience.

The computational functions of complex dendrites are also under intense investigation. There is a large body of literature regarding how different currents interact with geometric properties of neurons.

There are many software packages, such as GENESIS and NEURON, that allow rapid and systematic in silico modeling of realistic neurons. Blue Brain, a project founded by Henry Markram from the École Polytechnique Fédérale de Lausanne, aims to construct a biophysically detailed simulation of a cortical column on the Blue Gene supercomputer.

Modeling the richness of biophysical properties on the single-neuron scale can supply mechanisms that serve as the building blocks for network dynamics. However, detailed neuron descriptions are computationally expensive and this computing cost can limit the pursuit of realistic network investigations, where many neurons need to be simulated. As a result, researchers that study large neural circuits typically represent each neuron and synapse with an artificially simple model, ignoring much of the biological detail. Hence there is a drive to produce simplified neuron models that can retain significant biological fidelity at a low computational overhead. Algorithms have been developed to produce faithful, faster running, simplified surrogate neuron models from computationally expensive, detailed neuron models.

Modeling Neuron-glia interactions
Glial cells participate significantly in the regulation of neuronal activity at both the cellular and the network level. Modeling this interaction allows to clarify the potassium cycle, so important for maintaining homeostatis and to prevent epileptic seizures. Modeling reveals the role of glial protrusions that can penetrate in some cases the synaptic cleft to interfere with the synpatic transmission and thus control synaptic communication.

Development, axonal patterning, and guidance
Computational neuroscience aims to address a wide array of questions, including: How do axons and dendrites form during development? How do axons know where to target and how to reach these targets? How do neurons migrate to the proper position in the central and peripheral systems? How do synapses form? We know from molecular biology that distinct parts of the nervous system release distinct chemical cues, from growth factors to hormones that modulate and influence the growth and development of functional connections between neurons.

Theoretical investigations into the formation and patterning of synaptic connection and morphology are still nascent. One hypothesis that has recently garnered some attention is the minimal wiring hypothesis, which postulates that the formation of axons and dendrites effectively minimizes resource allocation while maintaining maximal information storage.

Sensory processing
Early models on sensory processing understood within a theoretical framework are credited to Horace Barlow. Somewhat similar to the minimal wiring hypothesis described in the preceding section, Barlow understood the processing of the early sensory systems to be a form of efficient coding, where the neurons encoded information which minimized the number of spikes. Experimental and computational work have since supported this hypothesis in one form or another. For the example of visual processing, efficient coding is manifested in the forms of efficient spatial coding, color coding, temporal/motion coding, stereo coding, and combinations of them.

Further along the visual pathway, even the efficiently coded visual information is too much for the capacity of the information bottleneck, the visual attentional bottleneck. A subsequent theory, V1 Saliency Hypothesis (V1SH), has been developed on exogenous attentional selection of a fraction of visual input for further processing, guided by a bottom-up saliency map in the primary visual cortex.

Current research in sensory processing is divided among a biophysical modelling of different subsystems and a more theoretical modelling of perception. Current models of perception have suggested that the brain performs some form of Bayesian inference and integration of different sensory information in generating our perception of the physical world.

Motor control
Many models of the way the brain controls movement have been developed. This includes models of processing in the brain such as the cerebellum's role for error correction, skill learning in motor cortex and the basal ganglia, or the control of the vestibulo ocular reflex. This also includes many normative models, such as those of the Bayesian or optimal control flavor which are built on the idea that the brain efficiently solves its problems.

Memory and synaptic plasticity
Earlier models of memory are primarily based on the postulates of Hebbian learning. Biologically relevant models such as Hopfield net have been developed to address the properties of associative (also known as "content-addressable") style of memory that occur in biological systems. These attempts are primarily focusing on the formation of medium- and long-term memory, localizing in the hippocampus.

One of the major problems in neurophysiological memory is how it is maintained and changed through multiple time scales. Unstable synapses are easy to train but also prone to stochastic disruption. Stable synapses forget less easily, but they are also harder to consolidate. It is likely that computational tools will contribute greatly to our understanding of how synapses function and change in relation to external stimulus in the coming decades.

Behaviors of networks
Biological neurons are connected to each other in a complex, recurrent fashion. These connections are, unlike most artificial neural networks, sparse and usually specific. It is not known how information is transmitted through such sparsely connected networks, although specific areas of the brain, such as the visual cortex, are understood in some detail. It is also unknown what the computational functions of these specific connectivity patterns are, if any.

The interactions of neurons in a small network can be often reduced to simple models such as the Ising model. The statistical mechanics of such simple systems are well-characterized theoretically. Some recent evidence suggests that dynamics of arbitrary neuronal networks can be reduced to pairwise interactions. It is not known, however, whether such descriptive dynamics impart any important computational function. With the emergence of two-photon microscopy and calcium imaging, we now have powerful experimental methods with which to test the new theories regarding neuronal networks.

In some cases the complex interactions between inhibitory and excitatory neurons can be simplified using mean-field theory, which gives rise to the population model of neural networks. While many neurotheorists prefer such models with reduced complexity, others argue that uncovering structural-functional relations depends on including as much neuronal and network structure as possible. Models of this type are typically built in large simulation platforms like GENESIS or NEURON. There have been some attempts to provide unified methods that bridge and integrate these levels of complexity.

Visual attention, identification, and categorization
Visual attention can be described as a set of mechanisms that limit some processing to a subset of incoming stimuli. Attentional mechanisms shape what we see and what we can act upon. They allow for concurrent selection of some (preferably, relevant) information and inhibition of other information. In order to have a more concrete specification of the mechanism underlying visual attention and the binding of features, a number of computational models have been proposed aiming to explain psychophysical findings. In general, all models postulate the existence of a saliency or priority map for registering the potentially interesting areas of the retinal input, and a gating mechanism for reducing the amount of incoming visual information, so that the limited computational resources of the brain can handle it. An example theory that is being extensively tested behaviorally and physiologically is the V1 Saliency Hypothesis  that a bottom-up saliency map is created in the primary visual cortex to guide attention exogenously. Computational neuroscience provides a mathematical framework for studying the mechanisms involved in brain function and allows complete simulation and prediction of neuropsychological syndromes.

Cognition, discrimination, and learning
Computational modeling of higher cognitive functions has only recently begun. Experimental data comes primarily from single-unit recording in primates. The frontal lobe and parietal lobe function as integrators of information from multiple sensory modalities. There are some tentative ideas regarding how simple mutually inhibitory functional circuits in these areas may carry out biologically relevant computation.

The brain seems to be able to discriminate and adapt particularly well in certain contexts. For instance, human beings seem to have an enormous capacity for memorizing and recognizing faces. One of the key goals of computational neuroscience is to dissect how biological systems carry out these complex computations efficiently and potentially replicate these processes in building intelligent machines.

The brain's large-scale organizational principles are illuminated by many fields, including biology, psychology, and clinical practice. Integrative neuroscience attempts to consolidate these observations through unified descriptive models and databases of behavioral measures and recordings. These are the bases for some quantitative modeling of large-scale brain activity.

The Computational Representational Understanding of Mind (CRUM) is another attempt at modeling human cognition through simulated processes like acquired rule-based systems in decision making and the manipulation of visual representations in decision making.

Consciousness
One of the ultimate goals of psychology/neuroscience is to be able to explain the everyday experience of conscious life. Francis Crick, Giulio Tononi and Christof Koch made some attempts to formulate consistent frameworks for future work in neural correlates of consciousness (NCC), though much of the work in this field remains speculative.

Computational clinical neuroscience
Computational clinical neuroscience is a field that brings together experts in neuroscience, neurology, psychiatry, decision sciences and computational modeling to quantitatively define and investigate problems in neurological and psychiatric diseases, and to train scientists and clinicians that wish to apply these models to diagnosis and treatment.

Predictive computational neuroscience
Predictive computational neuroscience is a recent field that combines signal processing, neuroscience, clinical data and machine learning to predict the brain during coma or anesthesia. For example, it is possible to anticipate deep brain states using the EEG signal. These states can be used to anticipate hypnotic concentration to administrate to the patient.

Computational Psychiatry
Computational psychiatry is a new emerging field that brings together experts in machine learning, neuroscience, neurology, psychiatry, psychology to provide an understanding of psychiatric disorders.

Neuromorphic computing
A neuromorphic computer/chip is any device that uses physical artificial neurons (made from silicon) to do computations (See: neuromorphic computing, physical neural network). One of the advantages of using a physical model computer such as this is that it takes the computational load of the processor (in the sense that the structural and some of the functional elements don't have to be programmed since they are in hardware). In recent times, neuromorphic technology has been used to build supercomputers which are used in international neuroscience collaborations. Examples include the Human Brain Project SpiNNaker supercomputer and the BrainScaleS computer.

Software

 * BRIAN, a Python based simulator
 * Budapest Reference Connectome, web based 3D visualization tool to browse connections in the human brain
 * Emergent, neural simulation software.
 * GENESIS, a general neural simulation system.
 * NEST is a simulator for spiking neural network models that focuses on the dynamics, size and structure of neural systems rather than on the exact morphology of individual neurons.

Journals

 * Journal of Mathematical Neuroscience
 * Journal of Computational Neuroscience
 * Neural Computation
 * Cognitive Neurodynamics
 * Frontiers in Computational Neuroscience
 * PLoS Computational Biology
 * Frontiers in Neuroinformatics

Conferences

 * Computational and Systems Neuroscience (COSYNE) – a computational neuroscience meeting with a systems neuroscience focus.
 * Annual Computational Neuroscience Meeting (CNS) – a yearly computational neuroscience meeting.
 * Neural Information Processing Systems (NIPS)– a leading annual conference covering mostly machine learning.
 * Cognitive Computational Neuroscience (CCN) – a computational neuroscience meeting focusing on computational models capable of cognitive tasks.
 * International Conference on Cognitive Neurodynamics (ICCN) – a yearly conference.
 * UK Mathematical Neurosciences Meeting– a yearly conference, focused on mathematical aspects.
 * Bernstein Conference on Computational Neuroscience (BCCN)– a yearly computational neuroscience conference ].
 * AREADNE Conferences– a biennial meeting that includes theoretical and experimental results.

Websites

 * Encyclopedia of Computational Neuroscience, part of Scholarpedia, an online expert curated encyclopedia on computational neuroscience and dynamical systems

title: Computational neuroscience