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Introduction to Art

This book is not designed to teach the reader how to be an artist, nor is it step-by step instruction on how to directly make art. This book is an overview of tools, procedures and creation paradigms for creating art within each of the major artistic disciplines.

Training a person to create art is not a subject that can be easily handled by any one book, at least not effectively. Learning to create art is a process that consists of directed practice and diligent study.

The aim of this book is to give the reader a better understanding for some of the individual components that generally make up artistic creation and the creative process.

Art, an Introduction

 * /Introduction/
 * /What is Art?/
 * /How to Use This Book/
 * /What is the Creative Process?/
 * /Conceptualizing A Work of Art/

 * /Art Throughout History/
 * /Where is Art Headed?/

Two-Dimensional

 * /The Basics of Two-Dimensional Art/

 * /Drawing I/ – Overview, Examples, and Tools Used
 * /Drawing II/ – Forms of Drawing (i.e. Line Drawing)
 * /Drawing Exercises/ – Exercises for Learning Drawing

 * /Painting I/ – Overview, Examples, and Tools Used
 * /Painting II/ – Forms of Painting (i.e. Water Colors)
 * /Paints (Water-Based)/ – Important Considerations for Water-Based Paints
 * /Paints (Oil-Based)/ – Important Considerations for Oil-Based Paints
 * /Paints (Wax-Based)/ – Important Considerations for Encaustic Paints
 * /Painting Exercises/ – Exercises for Learning Painting

 * /Digital Art I/ – Overview, Examples, and Tools Used
 * /Digital Art II/ – Forms of Digital Art (i.e. Vector Graphics)
 * /Digital Art (Color Schemes)/ – Important Considerations for Digital Color Schemes
 * /Digital Art Exercises/ – Exercises for Learning Making Digital Art

 * /Sculpture I/ – Overview, Examples, and Tools Used

 * /How to Make a Living/
 * /Practical Approach for the Artist/ – Learning how to market your Art, to whom, where and when. Resources.
 * /Legalities/ Learning copyrights, attribution laws, contractual arrangements. Keeping the books.
 * /Finer points for Contemporary Fine Artists/ – Overcoming "starving artist" mythology, how to make a living as an artist while you're still alive. Interviews with successful contemporaries.

Art History
See the dedicated text to Art History.
 * /Art History Basics/
 * Art History/Movements

Appendices

 * /References/
 * /Web Resources/

title: Introduction to Art


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Talk:Operating System Design/Case studies

Linux already has reliable journalling filesystems, several graphical interfaces, massive amounts of written documentation, etc. etc. Why would anybody want to use a DOS type of OS?? r3m0t (cont) (talk) 07:33, 17 Oct 2004 (UTC)

I agree - anyone who would consider basing an OS on DOS (even back in the 80's and early 90's when Microsoft was doing this with Windows) needs to learn more about the topic. DOS doesnt allow for much expansion (more filesystems), is single tasking (that means no running mozilla at the same time as notepad, and even GUIs themselves are almost unusable in this state) unless this is done manually by almost replacing all of DOS. The command line is defianately an advantage, however anyone familiar with a DOS command line would notice its almost impossible to work in by today's standards. Any Unix implementation has all the desirable features of DOS, only they actually are desirable for Unix - the command line is useable. Also, DOS offers no security whatsoever, any application can delete anything and stop the system from functioning and prevent recovery of any data. Unix is very secure (much moreso than Windows, this is a topic of debate, however anyone who has experience with both systems rather than just believing what microsoft says would defianately agree). Unix's only real shortcoming is the GUI - X11 is seriously slow and lacking in features desirable by the common user. While X is certainly more than sufficient for web browsing, word processing and most other things, benchmarks show that it is slower than Windows, and the fact alone that many applications look and behave differently is a serious problem. No GUI for DOS even competes with X however. I have deleted the FreeDOS section, no offence to the author, but it is misinforming.

How is this a wikibook topic? - anonymous

I don't think this belongs. It acts as if a new os is going to be created in the book. This is not the case according to the preface.

I have to agree with the above. This sounds like the author is going to document writing their own OS from scratch. Much better for this type of textbook (imho) would be to discuss the issues, and various approaches to resolving them. Using real life examples (particularly open source ones like Linux or the BSDs) to point the user to implementations that match specific approaches. For example most OSes have some kind of memory management, some kind of task scheduler, and some kind of file system. The actual implementations can vary massively, and there are many ways of dealing with the associated problems. In the spirit of this I'll try modifying this page to state more explicitly what could make this a good text book.

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


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File:Algorithms-F6CallTree.png

F(6) call tree created in paint

title: File:Algorithms-F6CallTree.png


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File:Algorithms-F6CallTreeMemoized.PNG

Memoized call-tree

title: File:Algorithms-F6CallTreeMemoized.PNG


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User:Gkhan/Fibonacci using memoization and DP

Fibonacci-function using memoization and DP
So how would a fibonacci program using memoization work? Consider the following program (f[n] contains the nth Fibonacci-number if has been calculated, -1 otherwise):

function fib(n) if f[n] != -1 return f[n] else if n == 0 or n == 1 return n else f[n] = fib(n-1) + fib(n-2) return f[n] fi end function

The code should be pretty obvoius. If the value of fib(n) already has been calculated it's stored in f[n] and then returned instead of calculating it again. That means all the copies of the sub-call trees are removed from the calculation.

The values in the blue boxes are values that already have been calculated and the calls can thus be skipped. It is thus alot faster than the straight-forward recursive algorithm. Since every value less than n is calculated once, and only once, the first time you execute it, the asymptotic running time is$$O (n)$$. Any other calls to it will take $$O (1)$$ since the values have been precalculated (assuming the rest of the calls is less than n).

The algorithm does consume alot of memory. When we calculate fib(n), the values fib(0) to fib(n) are stored in main memory. Can this be improved? Yes it can, although the $$O(n)$$ running time of subsequent calls are obvoisly lost (since the values aren't stored). Since the value of fib(n) only depends on fib(n-1) and fib(n-2) we can discard the other values by going bottom-up. If we want to calculate fib(n), we first calculate fib(2) (fib(0) + fib(1)) then we can calculate fib(3) by adding fib(1) and fib(2). Then we can discard fib(1) and fib(2) since we don't need them to calculate any more values. From fib(2) and fib(3) we calculate fib(4) and discard fib(2), then we calculate fib(5) and discard fib(3), etc etc. The code goes something like this:

function fib(n) int u = 0 int v = 1 int t; for i = 2 to n t = u + v u = v v = t repeat return v end function

We can, obvouisly, modify the code to store the values in an array for subsequent calls, the point is that we don't have to. This method is typical for dynamic programming. First we identify what subproblems need to be solved in order to solve the entire problem, and then we calculate the values bottom-up using an iterative process.


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United States Government/The Judicial Branch-Criticism

 * 1) /Should citizens being able to overrule the Supreme Court?/
 * 2) /Does the judicial branch upset the principle of checks and balances?/


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United States Government/Civic Society

 * 1) /Natural rights and Classical Republicanism in America/

title: United States Government/Civic Society


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United States Government/Constitutional Issues

Discussing The Constitution

 * 1) /Collected The Wisdom of all Ages?/


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User talk:65.69.50.84

Thank you for your contributions to the Radiation Oncology textbook. I would like to encourage you to continue to contribute. The page you edited, however, is the table of contents of the book. Any text should be on separate pages that link from the table of contents. That would be a more appropriate place to put new content. —Brim 22:57, 17 Oct 2004 (UTC)

title: User talk:65.69.50.84


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United States Government/The Judicial Branch-Criticism/Should citizens being able to overrule the Supreme Court?

Supreme Court decisions are often controversial; therefore giving citizens the right to approve or reject Supreme Court decisions would increase political participation. Court decisions often involve the most fundamental moral and political issues and citizens care enough to vote on them.

 * In 1902, Oregon introduced the initiative process which helped to raise voter turnout while it declined elsewhere. Due in part to this element of direct democracy, Oregon consistently has better than average turnout. Giving Americans a similar right could increase national turnout.

 * I disagree, this would not increase political participation. In the 2002 election in Oregon, which was dominated by ballot measures, only 42 percent turned out, contrasted with 60 percent in the 2000 Presidential election. Court cases would be similar to ballot measures in that they would only address one issue.

 * Further, there are deeper reasons why people don’t vote. There are still social and cultural barriers to voting by poor and minority citizens. Also, the cynicism of many voters wouldn’t be changed by this proposal.

 * The Constitution should be amended so citizens can approve or reject Supreme Court decisions. Currently, the Court has nearly unlimited power; far-reaching policy is often made by five unelected justices. This resembles more of a tyrannical aristocracy than a democracy. A vote would be the people’s opinion, rather than the political elite’s.

 * I disagree. First, the sheer impracticality to such as system is mind-boggling. How would we determine which case should be voted on? 5-4 rulings only? Or would we set up a nationwide initiative process? Perhaps we should only vote on a decision if 100,000 people march on Washington. Even the wording of a measure would ignite controversy. For example, most Americans are in favor of allowing two consenting adults to engage in sexual practices in the privacy of their own home. However, change ‘adults’ to ‘men’ and the results would be, in my opinion, quite different.

 * Further, This proposed system would dangerously upset our system of checks and balances and endanger minorities. The judicial branch is designed to be the final stop for most everything, and with a few exceptions, it has been. Changing this would effectively destroy the idea of Judicial Review as created in Marbury v. Madison.

 * The judiciary is the branch furthest from the turbulent emotions of the majority, and thus is the only one that can effectively protect the minority. Federalist ten expressed the Framers fears of rule by the majority; they were largely antimajoritarian; they knew that a government dominated by the majority would be no better to the minority than a monarchy. The Justices base their decisions on precedent and Constitutional history and wrestle with the complexity of the issue. Voters, on the other hand, would vote with their hearts, not with their minds.

 * Finally, court decisions already can be overturned through the Amendment process. This has occurred on several occasions; most notably in Scott v. Sanford and Oregon v. Mitchell. These two cases resulted in the 13th and the 26th Amendments, respectively.

 * A voting plan wouldn’t threaten basic rights. On the contrary, it would expand them by allowing citizens an opportunity to protect themselves from unjust laws. The entire population would become a jury. The sixth Amendment specifically grants the right to trial by jury; this would simply create the ultimate jury. Furthermore, the Supreme Court deals with upholding or rejecting existing laws, so technically rejecting a ruling could only delay the development of new rights not threaten established ones.

 * I disagree. This plan would definitely threaten basic rights. The US is a republic rather than a democracy to protect against overpowering majority rule. James Madison famously wrote, “Democracies…have in general been as short in their lives as they are violent in their deaths.” Decisions as important as Supreme Court cases should not be left up to the rash masses. There are many cases that would support my opinion.

 * For example, Romers v Evans, would likely have been rejected, thus allowing states to prohibit cities from enforcing ordinances protecting homosexuals, and permiting the violation of Evans rights.

 * Another example would be the Brown v Board of Education, which would likely have been overturned allowing for “separate but equal” to exist, which would inherently violate Linda Brown’s rights.


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United States Government/Civic Society/Natural rights and Classical Republicanism in America

Mr. Emore's Class : Heffernan vs. Classical Republicans (a dialogue)

GENERAL TENDENCY OF THE LAWS UNDER AMERICAN DEMOCRACY, AND INSTINCTS OF THOSE WHO APPLY THEM. Defects of a democratic government easy to be discovered--Its advantages discerned only by long observation--Democracy in America often inexpert, but the general tendency of the laws is advantageous--In the American democracy public officers have no permanent interests distinct from those of the majority--Results of this state of things.

THE defects and weaknesses of a democratic government may readily be discovered; they can be proved by obvious facts, whereas their healthy influence becomes evident in ways which are not obvious and are, so to speak, hidden. A glance suffices to detect its faults, but its good qualities can be discerned only by long observation. The laws of the American democracy are frequently defective or incomplete; they sometimes attack vested rights, or sanction others which are dangerous to the community; and even if they were good, their frequency would still be a great evil. How comes it, then, that the American republics prosper and continue?

In the consideration of laws a distinction must be carefully observed between the end at which they aim and the means by which they pursue that end; between their absolute and their relative excellence. If it be the intention of the legislator to favor the interests of the minority at the expense of the majority, and if the measures he takes are so combined as to accomplish the object he has in view with the least possible expense of time and exertion, the law may be well drawn up although its purpose is bad; and the more efficacious it is, the more dangerous it will be.

Democratic laws generally tend to promote the welfare of the greatest possible number; for they emanate from the majority of the citizens, who are subject to error, but who cannot have an interest opposed to their own advantage. The laws of an aristocracy tend, on the contrary, to concentrate wealth and power in the hands of the minority; because an aristocracy, by its very nature, constitutes a minority. It may therefore be asserted, as a general proposition, that the purpose of a democracy in its legislation is more useful to humanity than that of an aristocracy. This, however, is the sum total of its advantages.

Aristocracies are infinitely more expert in the science of legislation than democracies ever can be. They are possessed of a selfcontrol that protects them from the errors of temporary excitement; and they form far-reaching designs, which they know how to mature till a favorable opportunity arrives. Aristocratic government proceeds with the dexterity of art; it understands how to make the collective force of all its laws converge at the same time to a given point. Such is not the case with democracies, whose laws are almost always ineffective or inopportune. The means of democracy are therefore more imperfect than those of aristocracy, and the measures that it unwittingly adopts are frequently opposed to its own cause; but the object it has in view is more useful.

Let us now imagine a community so organized by nature or by its constitution that it can support the transitory action of bad laws, and that it can await, without destruction, the general tendency of its legislation: we shall then conceive how a democratic government, notwithstanding its faults, may be best fitted to produce the prosperity of this community. This is precisely what has occurred in the United States; and I repeat, what I have before remarked, that the great advantage of the Americans consists in their being able to commit faults which they may afterwards repair.

An analogous observation may be made respecting public officers. It is easy to perceive that American democracy frequently errs in the choice of the individuals to whom it entrusts the power of the administration; but it is more difficult to say why the state prospers under their rule. In the first place, it is to be remarked that if, in a democratic state, the governors have less honesty and less capacity than elsewhere, the governed are more enlightened and more attentive to their interests. As the people in democracies are more constantly vigilant in their affairs and more jealous of their rights, they prevent their representatives from abandoning that general line of conduct which their own interest prescribes. In the second place, it must be remembered that if the democratic magistrate is more apt to misuse his power, he possesses it for a shorter time. But there is yet another reason which is still more general and conclusive. It is no doubt of importance to the welfare of nations that they should be governed by men of talents and virtue; but it is perhaps still more important for them that the interests of those men should not differ from the interests of the community at large; for if such were the case, their virtues might become almost useless and their talents might be turned to a bad account. I have said that it is important that the interests of the persons in authority should not differ from or oppose the interests of the community at large; but I do not insist upon their having the same interests as the whole population, because I am not aware that such a state of things ever existed in any country.

No political form has hitherto been discovered that is equally favorable to the prosperity and the development of all the classes into which society is divided. These classes continue to form, as it were, so many distinct communities in the same nation; and experience has shown that it is no less dangerous to place the fate of these classes exclusively in the hands of any one of them than it is to make one people the arbiter of the destiny of another. When the rich alone govern, the interest of the poor is always endangered, and when the poor make the laws, that of the rich incurs very serious risks. The advantage of democracy does not consist, therefore, as has sometimes been asserted, in favoring the prosperity of all, but simply in contributing to the well-being of the greatest number. The men who are entrusted with the direction of public affairs in the United States are frequently inferior, in both capacity and morality, to those whom an aristocracy would raise to power. But their interest is identified and mingled with that of the majority of their fellow citizens. They may frequently be faithless and frequently mistaken, but they will never systematically adopt a line of conduct hostile to the majority; and they cannot give a dangerous or exclusive tendency to the government.

The maladministration of a democratic magistrate, moreover, is an isolated fact, which has influence only during the short period for which he is elected. Corruption and incapacity do not act as common interests which may connect men permanently with one another. A corrupt or incapable magistrate will not combine his measures with another magistrate simply because the latter is as corrupt and incapable as himself; and these two men will never unite their endeavors to promote the corruption and inaptitude of their remote posterity. The ambition and the maneuvers of the one will serve, on the contrary, to unmask the other. The vices of a magistrate in democratic states are usually wholly personal.

Voice 1: This philosophy represents how the individual over society, whereas classical republicanism advocates the betterment of society even when restricting personal liberty. Both these systems influenced the framers. Natural rights citizens form a social contract, consenting to form a government designed to protect their own interests. They participate to ensure the protection of their rights. Further, citizens can change the government if it fails to protect those rights. In Classical republicanism, citizens accept their obligation to the good of the whole. They participate because it is their civic duty. Citizens could rarely enter republics which effectively constrained them from leaving their own.

Voice 2: Ben Franklin believed the citizen’s rights often outweigh priorities of government. He said “they that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety.” Conversely, the Greek orator Pericles said, “The merits of a citizen outweigh the demerits of an individual.” To him and other classical republicans, sacrifices made for community were significant enough to offset personal errors.

Voice 3: The belief at the Convention was that classical republicanism would only work in small, homogeneous societies where citizens had similar goals. Therefore natural rights philosophy is more clearly exhibited in the Constitution, as in Article one Section nine, which prohibits the government from suspending important rights.

Voice 4: My definition of common good is the promotion of the good of society seen as a whole, as in classical republicanism.

Voice 1: The common good in respect to natural rights philosophy is the maximum amount of liberties for the individual. This is my definition of common good.

Voice 3: In my opinion each system is fatally flawed, they isolated paths to reach the common good. Classical republicanism discouraged individuality, punishing it by exile or death, as shown by the example of Socrates, who was executed for teaching people to question society. Natural rights societies do not ask their citizens to sacrifice for the good of the whole. Today’s drive for private gains ignores community goods like clean air, schools, and parks.

Voice 2: We purpose that the simultaneous advancement of society and the individual is the real common good. This is not a compromise or an average between classical republicanism and natural rights, the benefits of both systems are included entirely. In short, the common good is a fusion of these two extremes.

Voice 3: Historically politics has not used our definition due to its difficulty to attain. Instead they are compromises including some of both systems. In actuality, the common good is more than a perfect compromise, it is what is best for both at the same time. The framers understood this ideal; Madison said “the public Good, the real welfare of the great body of the people, is the supreme object to be pursued; no form of government… has any other value than as it may be fitted for the attainment of this object.”

Voice 1: My idea of common good, the natural rights theory, can be determined only by every individual deciding what is best for themselves.

Voice 4: I disagree. I believe in the classical republicanism take on common good, which is determined by the selfless wise for the benefit of society.

Voice 3: No, the common good is the selfless wise weighing the opinions of the masses to maximize the individual and collective goods.

Voice 2: Self-interest is looking out for ones own well-being. In contrast, enlightened self-interest is the idea that by helping society we in turn help ourselves. A simple way to distinguish between the two is by asking– Who is directly benefiting and for what reasons? As Du de la Rachefoucauld said, “However brilliant an action it should not be esteemed great unless the result of a great motive.”

Voice 4: Enlightened self-interest is disappearing from our society. It is largely due to social disconnect, lack of trust, feeling of powerlessness and because of the prevailing individualistic attitudes of Americans. The Tipping Point by Malcom Gladwell reveals that to create ideological epidemics one must solve the minute aspects of the problem. In short, to encourage enlightened self interest we should encourage domestic vacationing, labeling state origins of products, promote switching schools, teaching natural leaders to be civic, advocate public forums, providing tax benefits as a reward, and educating about benefits of enlightened self interest.


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Japanese/Background Japan

^ Japanese ^ | << Japanese tests | Background Japan | Internet links >>

History

 * Japanese Mythology Japanese Shinto and Buddhist mythology.
 * History of Japan (10,000 BC - present)
 * Japanese History (Jomon Period - Present)

Literature

 * Kojiki
 * Nihonshoki

Religion

 * Kūkai
 * Saichō
 * Japanese Buddhism
 * Zen Buddhism
 * Shinto Native Japanese religion.
 * Tendai Buddhism
 * Shingon Buddhism
 * Byōdōin Temple
 * Hōryu-ji Temple
 * Enryaku-ji Temple
 * Tōdai-ji Temple
 * O-mikuji

Arts

 * Ikebana The art of flower arrangement.
 * Origami The art of paper folding.
 * Shodō Calligraphy.
 * Ukiyo-e Japanese painting.
 * Japanese tea ceremony Known as chadō.
 * Sen no Rikyū
 * Sumo Sumo wrestlers.
 * Shōgun
 * Kimono
 * Tatami
 * Seiza

Food and Drink

 * Cuisine of Japan
 * Sashimi Sliced raw fish
 * Sushi Rolled vinegared rice with toppings
 * Miso Salty soy bean paste
 * Nattō Strong-smelling whole fermented soy beans
 * Wasabi Spicy green horseradish paste
 * Ramen
 * Soba
 * Udon
 * Matcha Powdered green tea
 * Sake Japanese rice wine

Society

 * Japanese Name
 * Japanese Media
 * Tōkyō Station
 * Mount Fuji
 * Nara Ancient capital of Japan.

Economy

 * Yen The Japanese currency.
 * Plaza Accord An agreement signed in New York to appreciate the Yen against the American Dollar.
 * GDP About Gross Domestic Product (GDP) and Japan's ranking in the global economy.

Politics

 * Emperor of Japan Known as Tennō.
 * Diet of Japan
 * Prime Minister of Japan
 * Constitution of Japan

 * MIT OpenCourseWare Japanese Pop Culture

^ Japanese ^ | << Japanese tests | Background Japan | Internet links >>

title: Japanese/Background Japan


text:
Talk:Japanese/Contributor's Guide

Configuring Japanese Scripts in my Computer
Hi,

How to configure Japanese Scripts in my Computer? If there is any software available for the above purpose, can you please post the same?

Thanks.

 * Hello, I think it would help to answer this question if you gave a little bit of information on the type of computer system you are using. i.e. Windows or Linux or Apple and which browser (Internet Explorer, Firefox, Chrome etc) and what their version numbers are.

title: Talk:Japanese/Contributor's Guide


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Handbook of Descriptive Statistics

This book aims to function as a comprehensive reference guide to the measures used in descriptive statistics. For a general introduction to statistics, see Statistics instead.

It has a section on all the common measures, and they are categorised according to type. Initially we shall concentrate on univariate statistics. Entries should be brief, information-packed and not overly tutorial in nature. Assume a reader which already has a basic knowledge of statistics, and needs detailed information or a refresher.

See /Template/ for how an entry should look.

Table of contents

 * 1) /Introduction/
 * 2) /Types of Statistical Variables/
 * 3) /Measures of Central Tendency/
 * 4) Arithmetic Mean
 * 5) Median
 * 6) Mode
 * 7) Midrange
 * 8) Geometric Mean
 * 9) Harmonic Mean
 * 10) Truncated Mean
 * 11) Interquartile Mean
 * 12) Root Mean Square
 * 13) Trimean
 * 14) Measures of Statistical Variability
 * 15) Variance
 * 16) Population Variance
 * 17) Standard Deviation
 * 18) Range
 * 19) Interquartile range
 * 20) Semiquartile range
 * 21) Absolute Deviation
 * 22) Geometric Standard Deviation
 * 23) Measures of Distribution Shape
 * 24) Skewness
 * 25) Kurtosis
 * 26) Chi-Squared Goodness of Fit
 * 27) Shapiro-Wilks W
 * 28) Kolmogorov-Smirnov test

title: Handbook of Descriptive Statistics


text:
Handbook of Descriptive Statistics/Template

This a template for how an entry in the Handbook of Descriptive Statistics should look. Please copy and paste the source of this page when creating a new entry.

Description

 * Brief description of what it is and what its used for.
 * Mathematical formula
 * Link to a Wikipedia article on it.

Usages
Describe in detail here data sets and purposes on which it is most useful. Describe also data sets for which it may give misleading results.

Distributions

 * Include standard values for common distributions, if they exist. For example, a normal distribution always has a skew and kurtosis of zero.
 * Include standard error for normal distribution, and for other distributions also if possible.
 * Sampling distribution.

Calculation
Include any alternative methods of calculation, especially for large data sets, or when other measures have already been calculated.

(An example: once you have the count, sum, sum of squares, cubes and fourth powers for a data set, you can then use these to easily calculate the Mean, Std. Dev, Skew and Kurtosis, rather than having to go through the entire dataset multiple times calculating differences.)

Software
Include how it is accessed in common statistical packages, if known. Can also provide links to source code samples for calculating it, etc.


text:
Handbook of Descriptive Statistics/Types of Statistical Variables

Statistical variables can be classified as follows:

Level of Measurement
The level of measurement of a variable in mathematics and statistics describes how much information the numbers associated with the variable contain. Different mathematical operations on variables are possible, depending on the level at which a variable is measured. In statistics, the kinds of descriptive statistics and significance tests that are appropriate depend on the level of measurement of the variables concerned.

Four levels of measurement are usually recognised:

 * Nominal measurement. The numbers are names or labels. They can and often are replaced by verbal names. If two entities have the same number associated with them, they belong to the same category, and that is the only significance that they have. The only comparisons that can be made between variable values are equality and inequality. There are no "less than" or "greater than" relations among them, nor operations such as addition or subtraction. Examples include: the international telephone code for a country, the numbers on the shirts of players in a sports team, or the number of a bus. The only kind of measure of central tendency is the mode. Information entropy is available as a measure of statistical dispersion, but no notion of standard deviation or the like exists. Variables that are measured only nominally are also called categorical variables.in other word it is used for qualitative data.
 * Ordinal measurement. The numbers have all the features of nominal measures and also represent the rank order (1st, 2nd, 3rd etc.) of the entities measured. The numbers are ordinals. Comparisons of greater and less can be made, in addition to equality and inequality. However operations such as conventional addition and subtraction are still without meaning. A physical example is the Mohs scale of mineral hardness. Another example is the results of a horse race; which horses arrived first, second, third, etc. are reported, but the time intervals between the horses are not reported. Most measurement in psychology and other social sciences is at the ordinal level; for example attitudes and IQ are only measured at the ordinal level. If customers surveyed report preferring chocolate- to vanilla-flavored ice cream, the data are of this kind. The central tendency of a distribution an ordinally measured variable can be represented by its mode or its median; the latter will give more information. Variables measured at the ordinal level are referred to as ordinal variables or rank variables.
 * Interval measurement. The numbers have all the features of ordinal measurement and also are separated by the same interval. In this case, differences between arbitrary pairs of numbers can be meaningfully compared. Operations such as addition and subtraction are therefore meaningful. However, the zero point on the scale is arbitrary, and ratios between numbers on the scale are not meaningful, so operations such as multiplication and division cannot be carried out. On the other hand, negative values on the scale can be used. An example is the year date in many calendars. The central tendency of a distribution an variable measured at the interval level can be represented by its mode, its median or its arithmetic mean; the mean will give most information. Variables measured at the interval level are referred to as interval variables, or sometimes as scaled variables, though the latter usage is not obvious and is not recommended.
 * Ratio measurement. This is the highest level of measurement and is used for quantitative data. The numbers have all the features of interval measurement and also have meaningful ratios between arbitrary pairs of numbers. Operations such as multiplication and division are therefore meaningful. The zero value on a ratio scale is non-arbitrary. Most physical quantities, such as mass, length or energy are measured on ratio scales; so is temperature when it is measured in kelvins, i.e., relative to absolute zero. The central tendency of a distribution an variable measured at the interval level can be represented by its mode, its median, its arithmetic mean, or its geometric mean; however as with an interval scale, the arithmetic mean will give the most useful information. Variables measured at the interval level are referred to as ratio variables.

Interval and/or ratio measurement are sometimes referred to as "true measurement", though this usage reflects a lack of understanding of the uses of ordinal measurement. However, it is only quantities measured on ratio scales that can correctly be said to have units of measurement.

Continuous and Discrete
Continuous variables are those variables that have theoretically an infinite number of gradations between two measurements. For example, body weight of individuals, milk yield of cows or buffaloes etc. Most of the variables in biology are of continuous type. Continuous variables arise from the process of measuring, i.e. assigning numerical values to objects according to explicit rules. The value of such variable is dependent on how precise the measuring instrument is. Discrete variables, on the other hand, do not have continuous gradations but there is a definite gap between two measurements, i.e. they can not be measured in fractions. For example, number of eggs laid by hens, number of children in a family etc. Discrete variables arise from the process of counting, thus regardless of the starting point, the value will always be the same.


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Talk:Handbook of Descriptive Statistics/Types of Statistical Variables

"Level of Measurement" copied from Wikipedia article of same name. --SimonK 03:32, 18 Oct 2004 (UTC)


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Handbook of Descriptive Statistics/Measures of Central Tendency/Arithmetic Mean

Description
Most commonly used measure of central tendency.

 * $$\overline{x} = \frac1n\sum_{i=1}^n x_i$$

Wikipedia article: Arithmetic mean

Usages

 * The mean may be conceived of as an estimate of the median. When the mean is not an accurate estimate of the median, the set of numbers, or frequency distribution, is said to be skewed.

 * The arithmetic mean is greatly influenced by outliers. For instance, reporting the "average" annual income in Redmond, Washington as the arithmetic mean of all annual incomes would yield a surprisingly high number because of Bill Gates. These distortions occur when the mean is different from the median, and the median is a superior alternative when that happens.

 * In certain situations, the arithmetic mean is the wrong concept of "average" altogether. For example, if a stock rose 10% in the first year, 30% in the second year and fell 10% in the third year, then it would be incorrect to report its "average" increase per year over this three year period as the arithmetic mean (10% + 30% + (−10%))/3 = 10%; the correct average in this case is the geometric mean which yields an average increase per year of only 8.8%.

Distributions

 * Include standard values for common distributions, if they exist. For example, a normal distribution always has a skew and kurtosis of zero.
 * Include standard error for normal distribution, and for other distributions also if possible.

For a normal distribution, the standard error of the mean is:

 * σM = σ / sqrt(N)

 * Sampling distribution.

Calculation
Include any alternative methods of calculation, especially for large data sets, or when other measures have already been calculated.

Microsoft Excel
It is relatively easy to determine the arithmetic mean, or average, in Microsoft Excel (v. '97, 2000, 2002/XP) by using a simple equation. Follow these steps to determine the mean in Excel for a set of data:

 * 1) Highlight an empty cell in the worksheet in which the mean will be calculated.
 * 2) Assuming that there are ten data points in cells A1 through A10, the following equation could be typed in the empty cell: "=AVERAGE(A1:A10)". Alternatively, this equation can also accept arguments in the form: "=AVERAGE(A1,A2,A3,...,A10)"

Refer to Microsoft Excels application documentation for further help.

Minitab
In Minitab (v. 14), finding the arithmetic mean is as simple as choosing options from the menu to display several descriptive statistics at once, including the arithmetic mean. Assuming again that there are ten valid data points in column C1, follow the steps below to display the mean:

 * 1) Go to the Menu bar at the top of the Minitab application and choose the following options: Stat -> Basic Statistics -> Display Descriptive Statistics...
 * 2) In the box labeled "Variables:" on the right hand side of the dialog box that appears, type "C1" and then click on the "OK" button in the bottom center of the dialog box. The mean will then be displayed in addition to other useful statistics in the 'Session' window of Minitab.


text:
Handbook of Descriptive Statistics/Measures of Statistical Variability/Variance

Description

 * Brief description of what it is and what its used for.
 * Mathematical formula
 * Link to a Wikipedia article on it.

Usages
Describe in detail here data sets and purposes on which it is most useful. Describe also data sets for which it may give misleading results.

Distributions

 * Include standard values for common distributions, if they exist. For example, a normal distribution always has a skew and kurtosis of zero.
 * Include standard error for normal distribution, and for other distributions also if possible.
 * Sampling distribution.

Calculation
A formula for calculating the variance σ2 of a population of size N is:
 * $$\sigma^2 = \frac 1N \sum_{i=1}^N (x_i - \mu)^2 = \frac 1N\sum_{i=1}^N x_i^2 - \mu^2 $$

Where:

 * $$\mu = \frac 1N \sum_{i=1}^N x_i$$

stands for the population mean.

A formula for calculating the sample variance s2, the unbiased estimation of the population variance, from a sample of size n, is:
 * $$s^2 = \frac 1{n-1} \sum_{i=1}^n (x_i - \bar{x})^2 = \frac {\sum_{i=1}^n x_i^2 - n \bar{x}^2}{n-1}$$

Where:

 * $$\bar{x} = \frac 1n \sum_{i=1}^n x_i$$

stands for the sample mean.

Algorithm
Therefore a simple algorithm to calculate variance can be described by the following pseudocode: double sum; double sum_sqr; double variance; long n = data.length; // the number of elements in the data array (the actual syntax is language-specific)

for i = 0 to n sum += data[i]; sum_sqr += ( data[i] * data[i] ); end for

variance = ((n * sum_sqr) - (sum * sum))/(n*(n-1));

Algorithm
Another algorithm which avoids large numbers in sum_sqr while summing up double avg; double var; long n = data.length; // number of elements

for i = 0 to n avg = (avg*i + data[i]) / (i + 1); if (i > 0) var += (var * (i - 1) + (data[i] - avg)*(data[i] - avg)) / i; end for

return var; // resulting variance

Another Algorithm
'corrected two pass algorithm' of Chan, Golub, Leveque (American Statistician, 1983, page 242): avg=0 for all i  avg=avg+data[i] end for avg=avg/n

sum=0 sum2=0 for all i   sum2=sum2+(data[i]-avg)^2 sum=sum+(data[i]-avg) end for var=(sum2-sum/n)/(n-1)

return var

Analysis of Algorithms
It is important, when dealing with large data sets or large numbers, on computers, to choose an algorithm which minimizes error due to approximate calculations by the computer. Merge in below discussion of the above algorithms.

It is actually the first formula that has precision problems when dealing with limited-precision arithmetic. If the difference between measurements and the mean is very small, then the first formula will yield precision problems, as information will be lost in the (xi - µ) operation. There is no such loss of significance in the intermediate operations of the second formula.

In fact, the second formula is the one more commonly beset with problems. The first can have problems when the mean is very large relative to the variance, but this is relatively rare in practice and this problem also affects the second formula. Much more common is the situation where you have comparable mean and variance and a very large number of observations. In this case, the second formula will result in the subtraction of two very large numbers whose difference is relatively small (by a factor roughly equal to the number of observations). If you have one million observations, you lose roughly six significant figures with the second formula if you use ordinary floating point arithmetic.

The problem may occur To be precise we have to specify the instrument and the nature of the data.
 * 1) when the deviations are very small relative to the mean or
 * 2) when they are small relative to the representational capacity of the arithmetic instrument (floating point computer, fixed point calculator, paper and pencil).

What do you mean by ordinary floating point arithmetic? Are talking about precision with respect to register width, or is there an implicit reference to some "non-ordinary" scheme, that is, non-IEEE? Thanks. I thought the reference was pretty explicit. I didn't mean, however, to imply the use of non-standard but still floating point arithmetic. I had in mind systems that were entirely different. A simple example is a system that uses rationals based on unlimited precision integers. Another system might be fixed point arithmetic. The first would not lose precision in the computation while the second would lose more or less precision than I quote depending on the values in question and the characteristics of the fixed point system. You could also imagine an optimizer that noted that you might be adding up large numbers of very small numbers and would re-order the addition to avoid most of the round-off error by using log N temporary values to perform the addition.

Software
Include how it is accessed in common statistical packages, if known. Can also provide links to source code samples for calculating it, etc.


text:
User:PrashantMullick

Became a member here on October 17, 2004

title: User:PrashantMullick


text:
Physiotherapy Assessment/General

General information
You should bear in mind that there are many variables that can affect the outcome of your assessment. The following is a (by no means exhaustive) list of possible factors influencing the patient (and condition) at the time of the session:

 * Time of day (are they tired after work or feeling fresh in the morning)
 * Temperature (extremes of hot and cold affect pain and stiffness)
 * Position (if sitting relieves their pain and they sit down for 20 minutes, it may have disappeared by the time you try to assess it)
 * Demeanour (if you’re abrupt with them, they won’t be very open with you)

The list goes on and on and it’s something that you’ll probably only begin to take note of as you gain experience. For now, just be aware that there’s more to the overall picture than what the patient says. Try to take notice of their body language as well as their verbal replies.

It’s important to make the patient feel as comfortable and relaxed as possible, as this will have a direct bearing on how open they are in discussing the problem with you. Remember, you’re probably going to ask them to remove at least a few items of clothing and to get into positions that in any other circumstances would be highly inappropriate. Think carefully about what you’re saying, as while it may be technically correct to say to the patient, “Take off your pants and bend over” when assessing the range of lumbar flexion, it may not be socially acceptable.

Use the subjective assessment as a period in which to make the patient feel calm and to try and create an atmosphere of trust.

Your assessment will almost always fall into 2 categories; the subjective and objective assessment. The subjective assessment, or interview, is used to try and work out the nature and cause of the patient’s symptoms. A good clinician will be able to get a very good idea of what’s going on just by speaking to the patient. The objective assessment is used both to eliminate other possible causes as well as to verify the hypothesis formed during the interview.

Personal details
Many outpatient settings will have their own forms for clinical notes. These differ greatly in layout but will always follow a similar sequence. The top of the form is usually reserved for the patient’s personal information, which is important to gather for the purposes of records. It usually consists of the following:

 * Name and surname
 * Date of birth
 * Telephone number
 * Address
 * Date of referral
 * Date of first appointment
 * Referring doctor/consultant/physiotherapist
 * There may be other information gathered, like medical chart number (if you're in a hospital setting), sex (‘male’ or ‘female’, not ‘often’), occupation and hobbies.

title: Physiotherapy Assessment/General


text:
Physiotherapy Assessment/Subjective

Subjective assessment
''Note: While the subjective assessment is examined in detail in this chapter, the objective assessment will be dealt with separately in each following chapter, as they will all be slightly different depending on the type of condition being assessed. Therefore, each chapter after this one will actually be an objective assessment of that type of condition i.e. the chapter on Respiratory assessments is actually a description of the objective assessment performed on a respiratory patient.''

Observation
Without saying a word, you could start picking information from the patient from the very first moment. This begins as soon as you see the patient in the waiting area and continues until they leave your company. Everything they do is a potential clue to their problem. Take note of how they’re sitting (or are they standing?). Do they look like they’re in pain? When they stand up, is it a struggle, or effortless? Watch them walk to the cubicle, do they limp, do they favour one side, are they steady on their feet? If they have to undress, watch them closely. If they’re saying they can’t lift up their arm and yet remove a T-shirt with no apparent discomfort, are they faking it (if it’s a medico-legal issue) or are they just having a pain-free day?

History of the Present Condition (Main problem)
You might begin your session (after taking details) with the following question, or one like it. “What seems to be the problem?” While this could elicit many responses, people will usually tell you what it is in terms of a functional deficit i.e. they’ll tell you what they can’t do, or name an activity that causes pain. You can’t expect a patient to reply, "Well Bob, I seem to have torn my left rotator cuff in what I think was a hyperextension injury." It’ll more than likely be something along the lines of, "It hurts when I sit for a long time", or "I can’t walk as far as I used to", or "My neck hurts when I type". You may occasionally get a response like: "My cow pushed me up against the wall", as I did when I treated a farmer with rib fractures. My first thought was that this guy had a very different approach to looking after his animals than more conventional farmers.

It’s part of your ability as a clinician to interpret these answers. As you gain experience you’ll start doing it subconsciously, but in the beginning it may take some effort. You’ll need to break the activities down into the likely actions/postures involved (are they sitting, standing, bending over, rotating, extending, jumping, running, etc.), analyse the functional muscle groups (what’s contracting, what’s relaxing?), think about the structures under duress (ligaments and tendons being strained) and figure out the potential causes (traumatic injury, arthritis, ‘wear and tear’, poor posture, fracture, etc.).

Body chart
The main problem is usually recorded on a body chart, all which have similar features and all are similarly asexual. The chart on the right is a more or less standard view of one. It shows an anterior and posterior view of the body (some charts have left and right views as well) and shows it in the anatomical position. It is the ideal place to reflect the description and relationship of symptoms. You could qualify them as following: nature, depth, frequency and impact. If the symptom is pain, you could add the VAS/NRPS grade. Some departments will have their own symbols for describing pain, stiffness, acute, chronic, whether it radiates, etc.

Behaviour of symptoms
A Typical 24-hour pattern; What aggravates it; What eases it; Any particular activities that bring on symptoms

Past Medical History (PMH)
It’s important to have a good understanding of the patient’s history at this point. You need to know whether this kind of thing happens often. Is it long-standing (chronic) or is it a recent thing?

Social/Family History (SH/FH)
FAMILY HISTORY: to rule out whether the pathological condition is due to hereditary transmission,example:diabetes also it can out the relationship with others

Past surgical history (PSH)
Have they had recent surgery that might give a clue to an underlying problem? If a patient has had a spinal fusion 6 months ago, and is now complaining of back pain, might the two be related?

Special questions

 * General health

 * Operations

 * Weight loss

 * Drugs (steroids, anticoagulants)

 * Rheumatoid arthritis (RA)

 * Osteoporosis

 * Diabetes

 * Spinal cord/Cauda equina symptoms

 * Dizziness

 * X-rays

 * Working environment

 * Constant or night pain

Life impact
What is the effect of the problem on their activities of daily living (Basic DLA, DLA and Participation): - Personal care - Home management - Social life and hobbies - Work

title: Physiotherapy Assessment/Subjective


text:
File:Body chart.jpg

Body chart for use in physiotherapy assessment

title: File:Body chart.jpg


text:
Wikibooks talk:Designated agent

Since this page is protected, please could an admin change the address to

This is the new official Wikimedia address. Thanks. Angela 19:37, 18 Oct 2004 (UTC)

 * Done. --mav 20:23, 18 Oct 2004 (UTC)

 * Thank you. Angela 02:46, 19 Oct 2004 (UTC)

Sorry to be a nuisance. Could the phone number change to 727-231-0101 and the address to board@wikimedia.org please. Angela 19:32, 19 Oct 2004 (UTC)

 * done. Gentgeen 20:34, 19 Oct 2004 (UTC)

The address has changed again. Please could an admin update it to

Wikimedia Foundation Inc. 200 2nd Ave. South #358 St. Petersburg, FL 33701-4313 +1 727 231 0101

Thanks. Angela 00:44, 30 September 2005 (UTC)

 * done. Gentgeen 08:17, 30 September 2005 (UTC)

Direct this page to Foundation
Please direct this page to

http://wikimediafoundation.org/wiki/Designated_agent

The correct & official information will always be kept there.

title: Wikibooks talk:Designated agent


text:
Geometry/Properties

Triangle Properties
Side-Side-Side (SSS) (Postulate 12)  If three sides of one triangle are congruent to three sides of a second triangle, then the two triangles are congruent.

Side-Angle-Side (SAS) (Postulate 13)

If two sides and the included angle of a second triangle, then the two triangles are congruent.

Angle-Side-Angle (ASA)

If two angles and the included side of one triangle are congruent to two angles and the included side of a second triangle, then two triangles are congruent.

Angle-Angle-Side (AAS)

If two angles and a non-included side of one triangle are congruent to two angles and the corresponding non-included side of a second triangle, then the two triangles are congruent.

NO - Angle-Side-Side (ASS)

The "ASS" postulate does not work, unlike the other ones. A way that students can remember this is that "ass" is not a nice word, so we don't use it in geometry (since it does not work).

title: Geometry/Properties


text:
How To Search/Boolean Logic

Boolean logic symbolically represents relationships between entities. There are three Boolean operators:

AND Use the AND operator to retrieve a set in which each citation contains all the search terms. This operator places no condition on where the terms are found in relation to one another; the terms simply have to appear somewhere in the same citation.

OR Use the OR operator to retrieve documents that contain at least one of the specified search terms.

Use OR when you want to pull together articles on similar subjects.

NOT Use the NOT operator to exclude the retrieval of terms from your search.

title: How To Search/Boolean Logic


text:
Cookbook:Meatballs

Meatballs are a class of food made of minced/ground meat shaped into a ball or similar oblong shape. The meat mixture may be bulked out with eggs and/or breadcrumbs, or seasoned with a range of ingredients. Meatballs are found in a wide variety of cultures and cuisines, where they can be stewed, baked, fried, grilled, and more.

Recipes
Recipes involving meatballs include:

 * Fried Meatballs
 * Swedish Meatballs
 * Italian Meatballs
 * Spaghetti and meatballs
 * Frikadelle

title: Cookbook:Meatballs


text:
Armour

This book consists of a set of short tutorials on making period armour and chain mail. We refer to items that are in or out of period in the context of which re-creation group we belong to. In the case of the armours presented here, the operational time span is that of the Society for Creative Anachronism, or the SCA. The 'uptime' cut-off date is 1600 CE, as the defining documents for the Society mandate a 'pre-16th century' mode of dress, etc. We allow a bit of leeway to include the years up to the death of Elizabeth I, at 1603 CE. The 'downtime' date(s) are a favourite argument topic; a rough estimate is 400 CE to 500 CE

Chapters:

 * /Making Basic Armour/
 * /Making Period Leather Armour/
 * /Making Period Mail/

title: Armour


text:
User:Publunch~enwikibooks

18th October 2004

Hello. My nick is publunch. If you go to my home page you might discover what my real name and my email address is. You might also find an old c.v./resume lying about. You'll see that I've been educated here and there. My certificates tell me that I'm supposed to know something about philosophy and one or two other things as well. When I got too old to be a perpetual student I got admitted to a mental hospital, but I haven't updated my c.v. since that happened. Generally people leave me alone these days, which means I may have time to make one or two minor contributions to wikipedia, wikiversity and so on, and might actually do me some good as well as benefitting other people.

21st March 2005

I haven't being doing much here, but I am still alive. I've been reading stuff about animal welfare and rights. I do a little bit of work for Compassion in World Farming. Indeed this seems to be taking up more and more time, so I have less time to work here.

title: User:Publunch~enwikibooks


text:
User:Dpbsmith

AKA w:User:Dpbsmith

title: User:Dpbsmith


text:
Introduction to Philosophy/What is Buddhist Philosophy?

Introduction
The Buddha expressed his philosophy when he said: "I teach only two things, O disciples, the nature of suffering and the cessation of suffering."

The Buddha taught the famous "Four Noble Truths" and "Eightfold Path," which allows people to achieve enlightenment. Enlightenment (nirvana, awakening, realization, satori) is the cessation of suffering, freedom from conditioned existence (samsara). The Buddha taught that every action has a consequence; things are because of previous conditions. If one practices the Four Noble Truths and the Eightfold Path, then one will no longer be subject to the cycle of existence samsara.

"My teaching is not a philosophy. It is the result of direct experience...

My teaching is a means of practice, not something to hold onto or worship.

My teaching is like a raft used to cross the river.

Only a fool would carry the raft around after he had already reached the other shore of liberation."

To his favourite disciple, Ananda, the Buddha once said (from: Old Path, White Clouds by Thich Nhat Hanh):

Three Marks of Existence

 * 1) Annica - Everything is subject to change.
 * 2) Dukkha - All pervasive unsatisfactoriness.
 * 3) Anatta - Everything is empty of a separate self.

Four Noble Truths

 * 1) Dukkha  - Life is unsatisfactory, disjointed, suffering.
 * 2) Samudaya - There is a cause of suffering, which is attachment or desire (tanha).
 * 3) Nirodha - There is a cessation of suffering, which is to eliminate attachment and desire.
 * 4) Marga   - The path that leads out of suffering is called the Noble Eightfold Path.

The Buddha taught that in order to realize enlightenment, man must free himself from his ego, and give up all desires. He taught that by having so many desires (such as wanting pleasure, wealth, happiness, security, success, long life, etc.), man subjects himself to suffering, and will never escape the cycle of rebirths.

Therefore Buddhism believes that suffering is self-created.

Wisdom - Prajna
1. Right Understanding (or Right View, or Right Perspective)

"And what, monks, is right understanding? Knowledge with regard to dukkha, knowledge with regard to the origination of dukkha, knowledge with regard to the stopping of dukkha, knowledge with regard to the way of practice leading to the stopping of dukkha: This, monks, is called right understanding.

2. Right Thought (or Right Intention, or Right Resolve)

"And what is right thought? Being resolved on renunciation, on freedom from ill will, on harmlessness: This is called right thought.

Morality - Sila
3. Right Speech

"And what is right speech? Abstaining from lying, abstaining from divisive speech, abstaining from abusive speech, abstaining from idle chatter: This, monks, is called right speech.

4. Right Action

"And what, monks, is right action? Abstaining from taking life, abstaining from stealing, abstaining from unchastity: This, monks, is called right action.

5. Right Livelihood

"And what, monks, is right livelihood? There is the case where a disciple of the noble ones, having abandoned dishonest livelihood, keeps his life going with right livelihood: This, monks, is called right livelihood.

Concentration - Samadhi
6. Right Effort (or Right Endeavour)

"And what, monks, is right effort? (i) There is the case where a monk generates desire, clout, endeavors, activates persistence, upholds & exerts his intent for the sake of the non-arising of evil, unskillful qualities that have not yet arisen. (ii) He generates desire, endeavors, activates persistence, upholds & exerts his intent for the sake of the abandonment of evil, unskillful qualities that have arisen. (iii) He generates desire, endeavors, activates persistence, upholds & exerts his intent for the sake of the arising of skillful qualities that have not yet arisen. (iv) He generates desire, endeavors, activates persistence, upholds & exerts his intent for the maintenance, non-confusion, increase, plenitude, development, & culmination of skillful qualities that have arisen: This, monks, is called right effort.

7. Right Mindfulness

"And what, monks, is right mindfulness? (i) There is the case where a monk remains focused on the body in & of itself -- ardent, aware, & mindful -- putting away greed & distress with reference to the world. (ii) He remains focused on feelings in & of themselves -- ardent, aware, & mindful -- putting away greed & distress with reference to the world. (iii) He remains focused on the mind in & of itself -- ardent, aware, & mindful -- putting away greed & distress with reference to the world. (iv) He remains focused on mental qualities in & of themselves -- ardent, aware, & mindful -- putting away greed & distress with reference to the world. This, monks, is called right mindfulness.

8. Right Concentration

"And what, monks, is right concentration? (i) There is the case where a monk -- quite withdrawn from sensuality, withdrawn from unskillful (mental) qualities -- enters & remains in the first jhana: rapture & pleasure born from withdrawal, accompanied by directed thought & evaluation. (ii) With the stilling of directed thought & evaluation, he enters & remains in the second jhana: rapture & pleasure born of concentration, one-pointedness of awareness free from directed thought & evaluation -- internal assurance. (iii) With the fading of rapture, he remains in equanimity, mindful & fully aware, and physically sensitive of pleasure. He enters & remains in the third jhana, of which the Noble Ones declare, 'Equanimous & mindful, he has a pleasurable abiding.' (iv) With the abandoning of pleasure & pain -- as with the earlier disappearance of elation & distress -- he enters & remains in the fourth jhana: purity of equanimity & mindfulness, neither pleasure nor pain. This, monks, is called right concentration."

Buddhism's world view
The Buddha taught that beings were born into their position because of past karma. He taught that there were six realms of existence: hell, insatiable-spirit, animal, fighting-spirits, human, and heavenly-being. A human birth was most desired because you have the best chance of enlightenment.

Summary

 * Life is dukha (suffering)
 * Karma: Cause-effect relationship.
 * Enlightenment: Escape from samsara.
 * Everything is marked by suffering, change and emptiness

 * Emptiness in this context means empty of an unchanging essence or self or soul.

 * The following quote by The Buddha summarizes many of his beliefs1:
 * On ignorance depends karma;
 * On karma depends consciousness;
 * On consciousness depend name and form;
 * On name and form depend the six organs of sense;
 * On the six organs of sense depends contact;
 * On contact depends sensation;
 * On sensation depends desire;
 * On desire depends attachment;
 * On attachment depends existence;
 * On existence depends birth;
 * On birth depends old age and death, sorrow, lamentation, misery, grief, and despair.


text:
User:Ford

O.T. Ford

Generalist in world studies, based in Los Angeles, but originally from West Lafayette, in Hoosierland. Particular interest in recent history, geography, language and symbols, and the nature and practice of dominion. Proponent of transcendent rationalism, and its corollary, stewardship.

Primary locations of my work: O.T. Ford — essays and commentaries Earth as it is — research on the state of the world

And a personal page: Of The Ford

I am primarily active in Wikipedia.

title: User:Ford


text:
Talk:Algebra/Variables

I just rewrote the page. As such an archived the previous discussions relating to the old page. There is a lot left to be added, specifically there should be a rather lengthy problems section. I am now thinking that order of operations should wait until its own section? We shall see. Thenub314 (talk) 08:57, 11 June 2010 (UTC)

Natural numbers
A recent edit changed "whole numbers" to "natural numbers" in a few places. This made sense because the text then gave as examples of whole numbers 1, 2, 3, … etc. I really wanted to stick with the term "whole" because I felt is was a bit more familiar, and I wanted to keep the terminology friendly at least until the formal definitions that come later in Sets. Thenub314 (talk) 21:00, 2 July 2010 (UTC)

Set notation
Hi I was hoping to remove the symbols { and } from the paragraph here. I wanted to avoid using set notation until after it is introduced section on sets a bit later on in the book. As the students I taught often don't understand what the notation means. I also was hoping to change leading sentence in Evaluating expressions to emphasize the idea that "variables are numbers". But I wanted to make sure there were no objections. Thenub314 (talk) 15:04, 14 July 2010 (UTC)

Editorial Opinions Welcome
I have no objection to any changes you want to make to the Algebra book.

I am currently working my way through it trying to make it "more conversational" while still keeping the rigor. The set notation is probably a style remnant from initializing arrays. Nfgdayton (talk) 19:30, 15 July 2010 (UTC)

Need to at least add answers to the problems given.
There are no answers given for teh problems shown at the bottom of th spage. This is needed. More practice problems would be nice as well. Kweeks (talk) 11:35, 6 September 2010 (UTC)

title: Talk:Algebra/Variables


text:
Puzzles/Easy Sequence 10/Solution

If one indexes the sequence from t, then the function for each term is trivially
 * $$a_n = \left\{\begin{matrix} 1\ \mathrm{if}\ n > t \\ 0\ \mathrm{otherwise} \end{matrix}\right.$$

Because this is the end of the easy sequences, you get something a bit more tricky - another solution:

 * $$a_n = \left\{\begin{matrix} 1\ \mathrm{if}\ n < t \\ 1\ \mathrm{if}\ t < n < t + 7 \\ 1\ \mathrm{if}\ t + 7 < n \\ 0\ \mathrm{otherwise} \end{matrix}\right.$$

Part of what mathematicians do is look for patterns. But be warned, just because it *looks* like it's doing something doesn't mean it's going to keep doing it forever! Showing that something does actually follow a pattern is some of what mathematicians spend their time on. But don't worry about that now, go look at some more sequences!

A bit too trivial for my liking, what about

$$a_n = (n + 4)\ \mathbf{div}\ 6$$

resulting in 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2...

What about any of these?

$$a_n = (n + k)\ \mathbf{div}\ (k+2)$$ with k >= 4

The sequence wasn´t supposed to necessarily change from 1 to 2 exactly after the ellipsis ("...").

another solution: $$a_n = (k*f(n))\ \mathbf{div}\ f(n)$$ with $$k \in \ ]1,2[$$

f(n) = f(n-1) ! for n > 1 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1...

title: Puzzles/Easy Sequence 10/Solution


text:
Cookbook:Rissoles

| Cuisine of Australia | Meat Recipes

Rissoles (ris·sole) is an extremely popular traditional Australian dish, similar to the American meatloaf.

Ingredients

 * 1 kg (2.2 lb) regular grade beef mince (ground beef)
 * ½ cup (40 g / 1.4 oz) breadcrumbs
 * 2 eggs
 * Gravy powder or flour
 * Various herbs

Procedure

 * 1) Place beef mince in mixing bowl with eggs, breadcrumbs and your favourite meat herbs and seasonings.
 * 2) Mix thoroughly. When fully mixed, remove one handful and mould into a the shape of a very thick hamburger patty.
 * 3) Roll the rissole in either flour or gravy powder (depending on your preferences).
 * 4) Cook in the oven, on a grill, or in a frying pan on a medium level of heat until cooked through and outer layer is crunchy.
 * 5) Serve with vegetables, hot chips, salad or by themselves on bread or toast to make rissole burgers.

title: Cookbook:Rissoles


text:
Statistics/Testing Data/z-tests2

Indications
The Null Hypothesis should be an assumption about the difference in the population means for two populations (note that the same quantitative variable must have been measured in each population). The data should consist of two samples of quantitative data (one from each population). The samples must be obtained independently from each other.

Requirements
The samples must be drawn from populations which have known Standard Deviations (or Variances). Also, the measured variable in each population (generically denoted x1 and x2) should have a Normal Distribution.

Note that if the distributions of the variables in the populations are non-normal (or unknown), the two-sample z-test can still be used for approximate results, provided the combined sample size (sum of sample sizes) is sufficiently large. Historically, a combined sample size of at least 30 has been considered sufficiently large; reality is (of course) much more complicated, but this rule of thumb is still in use in many textbooks.

Procedure

 * The Null Hypothesis:

 * H0 : μ1 - μ2 = δ

in which δ is the supposed difference in the expected values under the null hypothesis.

 * The Alternate Hypothesis:

 * H0 : μ1 - μ2 < δ

 * H0 : μ1 - μ2 > δ

 * H0 : μ1 - μ2 ≠ δ

For more information about the Null and Alternate Hypotheses, see the page on the z test for a single mean.

 * The Test Statistic:

 * $$z=\frac{(\bar{x}_1 - \bar{x}_2) - \delta}{\sqrt{\frac{\sigma _1^2}{n_1}+\frac{\sigma _2^2}{n_2}}}$$

Usually, the null hypothesis is that the population means are equal; in this case, the formula reduces to

 * $$z= \frac{\bar{x}_1 - \bar{x}_2}{\sqrt{\frac{\sigma _1^2}{n_1}+\frac{\sigma _2^2}{n_2}}}$$

In the past, the calculations were simpler if the Variances (and thus the Standard Deviations) of the two populations could be assumed equal. This process is called Pooling, and many textbooks still use it, though it is falling out of practice (since computers and calculators have all but removed any computational problems).

 * $$\frac{\bar{x}_1 - \bar{x}_2}

{\sigma \sqrt{\frac{1}{n_1} + \frac{1}{n_2}}} $$

 * The Significance (p-value)

Calculate the probability of observing a value of z (from a Standard Normal Distribution) using the Alternate Hypothesis to indicate the direction in which the area under the Probability Density Function is to be calculated. This is the Attained Significance, or p-value.

Note that some (older) methods first chose a Level Of Significance, which was then translated into a value of z. This made more sense (and was easier!) in the days before computers and graphics calculators.

 * Decision

The Attained Significance represents the probability of obtaining a test statistic as extreme, or more extreme, than ours—if the null hypothesis is true.

If the Attained Significance (p-value) is sufficiently low, then this indicates that our test statistic is unusual (rare)—we usually take this as evidence that the null hypothesis is in error. In this case, we reject the null hypothesis.

If the p-value is large, then this indicates that the test statistic is usual (common)—we take this as a lack of evidence against the null hypothesis. In this case, we fail to reject the null hypothesis.

It is common to use 5% as the dividing line between the common and the unusual; again, reality is more complicated.

Do Professors Make More Money at Larger Universities?
Universities and colleges in the United States of America are categorized by the highest degree offered. Type IIA institutions offer a Master's Degree, and type IIB institutions offer a Baccalaureate degree. A professor, looking for a new position, wonders if the salary difference between type IIA and IIB institutions is really significant.

He finds that a random sample of 200 IIA institutions has a mean salary (for full professors) of $54,218.00, with standard deviation $8,450. A random sample of 200 IIB institutions has a mean salary (for full professors) of $46,550.00, with standard deviation $9,500 (assume that the sample standard deviations are in fact the population standard deviations).

Do these data indicate a significantly higher salary at IIA institutions?

The null hypothesis is that there is no difference; thus

 * H0 : μA = μB

(where μA is the true mean full professor salary at IIA institutions, and μB is the mean at IIB institutions)

He is looking for evidence that IIA institutions have a higher mean salary; thus the alternate hypothesis is

 * H1 : μA > μB

Since the hypotheses concern means from independent samples (we'll assume that these are independent samples), a two sample test is indicated. The samples are large, and the standard deviations are known (assumed?), so a two sample z-test is appropriate.

 * $$z=\frac{\mu _A -\mu _B}{\sqrt{\frac{\sigma _A ^2}{n _A}+\frac{\sigma _B ^2}{n _B}}}=

\frac{54218-46550}{\sqrt{\frac{8450 ^2}{200}+\frac{9500 ^2}{200}}}= 8.5292$$

Now we find the area to the right of z = 8.5292 in the Standard Normal Distribution. This can be done with a table of values or software—I get 0.

If the null hypothesis is true, and there is no difference in the salaries between the two types of institutions, then the probability of obtaining samples where the mean for IIA institutions is at least $7,668 higher than the mean for IIB institutions is essentially zero. This occurs far too rarely to attribute to chance variation; it seems quite unusual. I reject the null hypothesis (at any reasonable level of significance!).

It appears that IIA schools have a significantly higher salary than IIB schools.

Example 2
A student scored 65 on a calculus test that had a mean of 50 and a standard deviation of 10; she scored 30 on history test with a mean of 25 and a standard deviation of 5.compare her relative position on the two tests?

title: Statistics/Testing Data/z-tests2


text:
Statistics/Testing Data/z-tests

The Null Hypothesis should be an assumption concerning the value of the population mean. The data should consist of a single sample of quantitative data from the population.

Requirements
The sample should be drawn from a population from which the Standard Deviation (or Variance) is known. Also, the measured variable (typically listed as $$x-\bar x$$ is the sample statistic) should have a Normal Distribution.

Note that if the distribution of the variable in the population is non-normal (or unknown), the z-test can still be used for approximate results, provided the sample size is sufficiently large. Historically, sample sizes of at least 30 have been considered sufficiently large; reality is (of course) much more complicated, but this rule of thumb is still in use in many textbooks.

If the population Standard Deviation is unknown, then a z-test is typically not appropriate. However, when the sample size is large, the sample standard deviation can be used as an estimate of the population standard deviation, and a z-test can provide approximate results.

Definitions of Terms

 * $$\mu_0$$ = Population Mean

 * $$\sigma$$ = Population Standard Deviation

 * $$\bar x$$ = Sample Mean

 * $$n$$ = Sample Population

Procedure

 * The Null Hypothesis:

This is a statement of no change or no effect; often, we are looking for evidence that this statement is no longer true.

 * H0 : μ = μ0

 * The Alternate Hypothesis:

This is a statement of inequality; we are looking for evidence that this statement is true.

 * H1 : μ < μ0 or

 * H1 : μ > μ0 or

 * H1 : μ ≠ μ0

 * The Test Statistic:

 * $$z=\frac{\bar x -\mu _0}{\sigma / \sqrt{n}}$$

 * The Significance (p-value)

Calculate the probability of observing a value of z (from a Standard Normal Distribution) using the Alternate Hypothesis to indicate the direction in which the area under the Probability Density Function is to be calculated. This is the Attained Significance, or p-value.

Note that some (older) methods first chose a Level Of Significance, which was then translated into a value of z. This made more sense (and was easier!) in the days before computers and graphics calculators.

 * Decision

The Attained Significance represents the probability of obtaining a test statistic as extreme, or more extreme, than ours - if the null hypothesis is true.

If the Attained Significance (p-value) is sufficiently low, then this indicates that our test statistic is unusual (rare) - we usually take this as evidence that the null hypothesis is in error. In this case, we reject the null hypothesis.

If the p-value is large, then this indicates that the test statistic is usual (common) - we take this as a lack of evidence against the null hypothesis. In this case, we fail to reject the null hypothesis.

It is common to use 5% as the dividing line between the common and the unusual; again, reality is more complicated. Sometimes a lower level of uncertainty must be chosen should the consequences of error results in a decision that can injure or kill people or do great economic harm. We would more likely tolerate a drug that kills 5% of patients with a terminal cancer but cures 95% of all patients, but we would hardly tolerate a cosmetic that disfigures 5% of those who use it.

Are The Kids Above Average?
Scores on a certain test of mathematical aptitude have mean μ = 50 and standard deviation σ = 10. An amateur researcher believes that the students in his area are brighter than average, and wants to test his theory.

The researcher has obtained a random sample of 45 scores for students in his area. The mean score for this sample is 52.

Does the researcher have evidence to support his belief?

The null hypothesis is that there is no difference, and that the students in his area are no different than those in the general population; thus,

 * H0 : μ = 50

(where μ represents the mean score for students in his area)

He is looking for evidence that the students in his area are above average; thus, the alternate hypothesis is

 * H1 : μ > 50

Since the hypothesis concerns a single population mean, a z-test is indicated. The sample size is fairly large (greater than 30), and the standard deviation is known, so a z-test is appropriate.

 * $$z=\frac{\bar x -\mu _0}{\sigma / \sqrt{n}} =\frac{52-50}{10/ \sqrt{45}}=1.3416$$

We now find the area under the Normal Distribution to the right of z = 1.3416 (to the right, since the alternate hypothesis is to the right). This can be done with a table of values, or software- I get a value of 0.0899.

If the null hypothesis is true (and these students are no better than the general population), then the probability of obtaining a sample mean of 52 or higher is 8.99%. This occurs fairly frequently (using the 5% rule), so it does not seem unusual. I fail to reject the null hypothesis (at the 5% level).

It appears that the evidence does not support the researcher's belief.

Is The Machine Working Correctly?
Sue is in charge of Quality Control at a bottling facility. Currently, she is checking the operation of a machine that is supposed to deliver 355 mL of liquid into an aluminum can. If the machine delivers too little, then the local Regulatory Agency may fine the company. If the machine delivers too much, then the company may lose money. For these reasons, Sue is looking for any evidence that the amount delivered by the machine is different from 355 mL.

During her investigation, Sue obtains a random sample of 10 cans, and measures the following volumes:

 * 355.02 355.47 353.01 355.93 356.66 355.98 353.74 354.96 353.81 355.79

The machine's specifications claim that the amount of liquid delivered varies according to a normal distribution, with mean μ = 355 mL and standard deviation σ = 0.05 mL.

Do the data suggest that the machine is operating correctly?

The null hypothesis is that the machine is operating according to its specifications; thus

 * H0 : μ = 355

(where μ is the mean volume delivered by the machine)

Sue is looking for evidence of any difference; thus, the alternate hypothesis is

 * H1 : μ ≠ 355

Since the hypothesis concerns a single population mean, a z-test is indicated. The population follows a normal distribution, and the standard deviation is known, so a z-test is appropriate.

In order to calculate the test statistic (z), we must first find the sample mean from the data. Use a calculator or computer to find that $$\bar x = 355.037$$.

 * $$z=\frac{\bar x -\mu _0}{\sigma / \sqrt{n}} =\frac{355.037-355}{0.05/ \sqrt{10}}=2.34$$

The calculation of the p-value will be a little different. If we only find the area under the normal curve above z = 2.34, then we have found the probability of obtaining a sample mean of 355.037 or higher—what about the probability of obtaining a low value?

In the case that the alternate hypothesis uses ≠, the p-value is found by doubling the tail area—in this case, we double the area above z = 2.34.

The area above z = 2.34 is 0.0096; thus, the p-value for this test is 0.0192.

If the machine is delivering 355 mL, then the probability of obtaining a sample mean this far (0.037 mL) or farther from 355 mL is 0.0096, or 0.96%. This is pretty rare; I'll reject the null hypothesis.

It appears that the machine is not working correctly.

N.B.: since the alternate hypothesis is ≠, we cannot conclude that the machine is delivering more than 355 mL—we can only say that the amount is different from 355 mL.

title: Statistics/Testing Data/z-tests


text:
Talk:Introduction to Philosophy/Existentialism

Well, content of this page is fair enough. I can't see why it is put under the broader title 'ethics' however. Like Sartre's Being and Nothingness, which I consider to be one of the core texts of existentialism, has the subtitle An Essay on Phenomenological Ontology. If no-one objects, I might soon move this page to a different chapter of the textbook.

--publunch 09:38, 19 Oct 2004 (UTC)

It's worth noting that most existentialists - including Sartre who first coined the term - would reject that they were part of a 'movement'. Kierkegaard didn't call himself an existentialist, and it wasn't until the 20th Century that people used that term in reference to him. - Tom M

"Apathy" is a misnomer as used in "One existentialist feeling is nausea, another is apathy." Existentialism might seem at first to condone a nihilistic lifestyle, but an apathetic existentialist is failing to be an existentialist. --Mute.prophet 12:18, 4 December 2007 (UTC)

I thought that "Nothing is real, all is permissible" was originally attributed (falsely) as the last words of Hassan-i Sabbah by a historian of the period. Neither existentialist. ~ 24.130.102.249 (talk) 00:12, 11 February 2009 (UTC)


text:
Talk:XML - Managing Data Exchange/Parsing XML files

I have revised the chapter. A few comments:

-Overall the chapter is a lot to swallow. Some of the parsers are based off Java code, some are based off of .NET, and one is bassed off of Tcl, a language I have never seen before. Maybe we should focus on a few parsers that are relavent to our class.

-This chapter lacks diagrams, maybe a diagram to show the relationship between xml files, parsers, and 'client applications'.

-The example given is based of movies rather than tourguide. Hopefully this could stay this way because I still don't really understand the exact mechanics of how parsers work and the possibility of me incorrectly changing the examples are extremely high.

--67.34.230.240 19:47, 5 March 2006 (UTC)Andy Sytsma

= Editorial Board =

Viji - 3/8/06

 * I think that just focusing on Java is best (therefore eliminating the .net and all other languages)

 * The examples should in some way be related to the Tourism example. If you are to teach this chapter to the class it will be an excellent way for you to prepare by creating your own example.  Remember that Dr. Watson is an excellent resource and that you can ask him for help.

Thanks, viji

Christina - 3/8/06

Good feedback, Andy. You're right--this chapter is quite a bit to swallow.

 * I concur with Viji's comment about the Java focus and tourism example.

 * Modify the chapter learning objectives to match your plan for the narrowed focus of the chapter.

 * You should verify comments about previous chapters. The Java parsing content has been removed from those chapters, so references to Java parsing in past chapters should be removed.

 * It may be worth looking at the history of the beginning chapters to review the Java parsing content that used to exist in those chapters.

 * Definitely follow the checklist. I tried to use the checklist for this chapter, and I could only check off a few of the many author guidelines in the checklist.

= Professor = I agree with the focus on Java and the addition of some diagram. Move the other material to an appendix for this chapter. A tourism example should not be hard to create. Remember to follow the guidelines and the checklist. Check that the code works and for class create a problem for students to parse a given xml file. They should be able to modify the sample code.

Rtw 16:10, 8 March 2006 (UTC)


text:
User talk:Nelson castaneda

EJERCICIO 11 (Si es compuesta)

un tractor cuesta $120,000 cada año se devalua en 8% de su precio original. Encuentre la fôrmula para el valor (V) de la maquina en (T)años.

¿Que proponen?? Encontrar la formula para el valor (V) de la maquina en (T) años.

¿Que nos dan? El valor de el tractor $120,000 y el porcentage 8%con el cual se devalua cada año de su precio original.

Solucion

I=valor en que se devalua P=precio del tractor R=% de devaluacion

$$I=P(R/100)$$

La sucesiôn de valores es: $$P, P-I, P-2I, P-3I, P-4I,....$$

Despues de t años el valor esta dado por

$$V(t)=P-t*I$$

en este caso:$$P=120,000 Y R=8\%$$

$$I=P(R/100)$$ $$\Rightarrow\I=120,000(8/1000)=9600$$

Despues de t años, el valor total devaluado sera

$$t*I=9600T$$, por lo tanto $$V(t)=p-tI=120,000-9600t$$

=$$V(t)=120,000-9600t$$

EJERCICIO 11 (Si no es compuesta) Si la devaluacion de tractor no es de su precio original sin no apartir de la precio anterior despues de insertarle la devaluacion.

Se devalua 8% o vale 92% cada año. ¿porque? $$100-8\%=92\%$$

Que nos dan?

a=valor inicial=120,000 r=valor cada año =23/25 t=tiempo en años $$92/100=46/50=23/25$$ (se simplifica)

$$23/25 de 120,000 $$ es el valor de la maquina al termino de un año.

$$23/25 de 120,000=120,000*(23/25)$$

Al segundo año $$=120,000(23/25)^2$$

=V(t)=a*r^t-1 \Rightarrow\V(t)=120,000(23/25)^t-1</m

EJERCICIO 3.27 Demostrar por generalizacion la ley de Morgan

$$(/cup/_{i=0) ^n A_i)'=/cap/_{i=0} ^n  A_i$$

Demostrar para el primer caso:

suponiendo valido para n=k

$$(/cap/_{i=1} ^k A_i)'=/CUP/_{i=1}^k  A__i$$ H.I

debo demostrar, usando HI que: $$(/cap/_{i=1} ^k A_i)'=(/cup/_{i=1} ^{k+1} A_i)'$$

$$(/cap/_{i=1} ^{k+1} A_i)=/cup/_{i=1} ^{k+1} A_i$$

$$(/cap/_{i=1} ^k A_i) /cap/ A_{k+1}'= /cup/_{i=1} ^k  A_i /cup/ A^1 _{k+1}$$

Ejercio 3.24

Demostrar que la suma de los $$n$$ primeros numeros impares es $$n^2$$

Que es una sucession?

Por ejemplo la sucession dada por la suma de los #'s impares:

$$s=1+3+5+7...2n-1$$

Tiene la propiedad comutativa:

$$s=2n-1......5+3+1$$

Al sumar las dos expresiones anteriores

$$s=1+3+5.....2n-1$$ $$s=2n-1....5+3+1$$

tendremos $$2s=(2n-1)+1$$ se puede escribir de esta manera:$$2s=[(2n-1)+1]n$$

despejando $$s</math\%$$

title: User talk:Nelson castaneda