Jean-François Stich

Monideepa Tarafdar

Patrick Stacey

Cary L Cooper

EMAIL LOAD, WORKLOAD STRESS AND DESIRED EMAIL LOAD: A CYBERNETIC APPROACH

Keywords: Email Stress, Email Load, Cybernetic Theory, Workplace Stress, Email Overload, Technostress

Purpose -Using email is a time-consuming activity that can increase workload stress. This paper investigates the relationship between the individual's email load, workload stress and desired email load, drawing from the cybernetic theory of stress.

Design/methodology/approach -Based on prior theory, we first hypothesized relationships among email load, workplace stress and desired email load. We then tested these relationships on a sample of 504 full-time workers in the U.S., using survey data and covariance based structural equation modeling techniques.

Findings -We find that (1) higher email load is associated with higher workload stress; (2) higher workload stress is associated with lower desired email load; (3) lower desired email load is associated with lower email load; and (4) higher workload stress is associated with higher psychological strain, higher negative emotions, and lower organizational commitment.

Originality/value -The study provides a novel understanding of workload stress due to email load, through the lens of cybernetic theory. It contributes to the email overload and technostress literatures by conceptualizing desired email load as a potential outcome of workplace stress and as a regulator for email load. For practitioners, the study highlights the importance of managing employees' email load to prevent the negative effects of workplace stress and associated strains.

INTRODUCTION

Checking, receiving, reading, sending and sorting through email are time-consuming activities that have a clear influence on workload stress for employees [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Jackson | A simple approach to improving email communication[END_REF]. This is especially so in situations of unsuitable email use such as unnecessary email carbon copying [START_REF] Kimble | The role of contextual clues in the creation of information overload[END_REF][START_REF] O'kane | Workplace interactions and the polymorphic role of e-mail[END_REF][START_REF] Thomas | Reconceptualizing E-Mail Overload[END_REF]. This influence of email load on workload stress may cause individuals to develop perceptions that the email medium is a reason for workload stress [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF], and hence to desire a lower email load (i.e. to distance themselves from the stressful source). In situations where individuals do have some control over their email load [START_REF] Derks | Smartphone use and work-home interference: The moderating role of social norms and employee work engagement[END_REF], their desire to disengage from email may result in reduced email use and a lower email load. However, it can be difficult for individuals to reduce their email load, as emails continue to be sent to them [START_REF] Derks | Smartphone use and work-home interference: The moderating role of social norms and employee work engagement[END_REF][START_REF] Renaud | You've Got E-Mail!' ... Shall I Deal With It Now? Electronic Mail From the Recipient's Perspective[END_REF]. Moreover, individuals who evaluate their email load rarely do so in a detached, objective and attitudefree manner. Individuals who hold negative attitudes towards email generally appraise workload stress more [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Sobotta | A Capacity Perspective on E-Mail Overload: How E-Mail Use Contributes to Information Overload[END_REF]. In all of these examples, the individual's desired email load has emerged as an important concept that shapes why he or she finds email use to be stressful.

However, the literature has not examined the concept of desired email load, specifically its antecedents or consequences. Although the relationship between the individual's email load and workload stress have been investigated (E.g., [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Jackson | A simple approach to improving email communication[END_REF], the relationships between the individual's email load, workload stress and desired email load have not. The objective of this study is to examine the concept of desired email load. We do so by developing and testing a research model between an individual's email load, desired email load, and workplace stress, based on the cybernetic theory of stress [START_REF] Carver | Control theory: A useful conceptual framework for personality-social, clinical, and health psychology[END_REF][START_REF] Liang | Avoidance of Information Technology Threats: A Theoretical Perspective[END_REF]. The principles of the cybernetic approach to stress explain how individuals react to stressful encounters by trying to distance themselves away from the stressful state and to move toward more desirable states. It is a helpful conceptual approach for understanding why desired email load is an important concept which guides individuals' experience of stress from the use of the email medium. It provides therefore an appropriate theoretical lens to examine the relationships between email load, desired email load, and workload stress. We establish the positive influence of the individual's email load on workload stress. More importantly, we investigate how individuals' workload stress can be negatively related to their desired email load as they distance themselves from the source of stress, and how their desired email load is positively related to email load. To our knowledge, these latter two relationships have not been investigated in literature on email overload, and constitute a novel aspect of our understanding of email load [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF].

Guided by prior research on email load and work stress, and the overarching theoretical framework of the cybernetic theory of stress, we adopt a deductive research design in this study. Specifically, we first framed hypothesized relationships among email load, workplace stress and desired email load. We then tested these relationships on a sample of 504 full-time workers in the U.S., using survey data and structural equation modeling techniques. We found that email load was positively related to workload stress. Workload stress was positively related to psychological strain and negative emotions, and negatively related to organizational commitment and desired email load. Finally, desired email load was positively related to email load.

The paper is organized as follows. The next two sections present the theoretical background and our research hypotheses respectively. The fourth section presents the methods of the study. The fifth section details the results of the model testing. The last section discusses the results and their theoretical and practical implications, along with the study's limitations.

THEORY BACKGROUND

Email load and workload stress

Research has frequently discussed the potential of email to increase workload. The volume of emails sent and received is particularly exacerbated by the speed and convenience of sending emails to multiple recipients [START_REF] Taylor | E-mail at work: A cause for concern? The implications of the new communication technologies for health, wellbeing and productivity at work[END_REF][START_REF] Thomas | Reconceptualizing E-Mail Overload[END_REF][START_REF] Vidgen | Understanding e-mail overload[END_REF][START_REF] Yan | A conceptual model of technology features and technostress in telemedicine communication[END_REF], the extensive use of the 'copy' function [START_REF] Ingham | E-mail overload in the UK workplace[END_REF][START_REF] Kimble | The role of contextual clues in the creation of information overload[END_REF], and the sending of irrelevant information [START_REF] O'kane | Workplace interactions and the polymorphic role of e-mail[END_REF]. It has been estimated that 125 billion work emails are sent and received every daya number forecasted to grow to year after year [START_REF] Radicati | Email statistics report[END_REF].

Reports have further found that 80% of work email are opened [START_REF] Dietzen | Email Use 2017 -EMEA report[END_REF]. The activity of reading and sending emails can thus become significantly time-consuming in current-day workplaces [START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF]. It has been estimated that, in 2006, employees spent on average 29 minutes per day reading emails, let alone sending and answering them [START_REF] Jackson | A simple approach to improving email communication[END_REF]. More recent reports have estimated that receiving, reading and sending work email consume, every day, from one hour and a half (Ofcom, 2016) to over two hours and a half [START_REF] Dietzen | Email Use 2017 -EMEA report[END_REF]. These estimations mirror the finding that the more emails received, the longer the perceived workday and the greater the feelings of workload stress [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF]. Although some work-related emails can increase work effectiveness [START_REF] Mano | E-mail characteristics, work performance and distress[END_REF], others distract employees from accomplishing other tasks [START_REF] Burgess | Email training significantly reduces email defects[END_REF], potentially leading to increased feelings of workload stress.

Studies on email load also focus on interruption of workflow due to email. A high daily volume of emails is often a sign of frequent emails throughout the workday. A report found that 62% of employees leave their email inbox open all day (Future Work Centre, 2015).

Every incoming email is potentially notified to employees. Within a large UK company, employees were found to react to the majority of these notifications in under six seconds [START_REF] Jackson | The cost of email interruption[END_REF]. Such prompt reactions necessarily fragment employees' attention and make it harder for them to return to the tasks that they were working on prior to the interruption. According to this study, employees took an average of 64 seconds to return to their main activity following an email interruption [START_REF] Jackson | The cost of email interruption[END_REF]. [START_REF] Gupta | SIMONE: A Simulator for Interruptions and Message Overload in Network Environments[END_REF] estimated that knowledge workers lose four to five percent or 28 minutes of their workday because of such interruptions. To avoid being interrupted by email, individuals adopt various email management practices such as checking email in batches. Studies have shown however that such practices still do not lead to lower workload stress [START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF].

A third aspect of research on email load focuses on email overload. Email overload has been defined as the perception of the individual that his or her email load is "out of control because they receive and send more email than they can handle, find or process effectively" (Dabbish & Kraut, 2006, p. 431). In general, the higher the volume of emails, the higher the perceptions of email overload [START_REF] Soucek | Coping with information overload in email communication: Evaluation of a training intervention[END_REF][START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF].

Other predictors of email overload include email interruptions [START_REF] Wajcman | Constant Connectivity: Rethinking Interruptions at Work[END_REF], time spent managing email [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF], email batching [START_REF] Whittaker | Email Overload: Exploring Personal Information Management of Email[END_REF] or too many email folders [START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF]. These predictors exemplify the multiple ways in which email can increase workload and perceptions of being overwhelmed. Email overload has been associated with an increased risk of burnout, sleep disorders and emotional distress [START_REF] Barber | Please Respond ASAP: Workplace Telepressure and Employee Recovery[END_REF][START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF][START_REF] Jackson | Theory-based model of factors affecting information overload[END_REF][START_REF] Mano | E-mail characteristics, work performance and distress[END_REF].

Fourthly, the technostress literature, which addresses the phenomenon of stress due to the use of ICT, also acknowledges the stress creating effects of applications such as email [START_REF] Tarafdar | The technostress trifectatechno eustress, techno distress and design: An agenda for research[END_REF]. Information overload, which is a potential correlate of email overload, is encompassed in the techno-overload dimension of technostress creating conditions [START_REF] Tarafdar | The Impact of Technostress on Role Stress and Productivity[END_REF]. Email is now ubiquitous and often accessed anytime, anywhere (Eurofound and the International Labour Office, 2017). Employees who access email outside contracted hours work longer hours (Eurofound and the International Labour Office, 2017), which could almost account for an extra day of unpaid overtime per week (BBC News, 2014). Workload stress due to email overload can, therefore, spill over into employees' personal lives [START_REF] Stich | Electronic communication in the workplace: boon or bane? Journal of Organizational Effectiveness: People and Performance[END_REF]. The techno-invasion dimension of technostress creating conditions captures this perception that ICT has invaded one's personal life [START_REF] Barber | Please Respond ASAP: Workplace Telepressure and Employee Recovery[END_REF][START_REF] Day | Perceived information and communication technology (ICT) demands on employee outcomes: The moderating effect of organizational ICT support[END_REF][START_REF] Tarafdar | The Impact of Technostress on Role Stress and Productivity[END_REF].

Finally, we make a note of how email load is assessed. We define 'email load' as the extent of email sent, read and received by the individual. Literature shows that individuals' perception of their email activity is a good indicator of their email load [START_REF] Karr-Wisniewski | When more is too much: Operationalizing technology overload and exploring its impact on knowledge worker productivity[END_REF].

Studies also show that in order to prevent cognitive overload, individuals assess their information processing (in this case their email use) activity through simple and manageable criterion [START_REF] Browne | Cognitive stopping rules for terminating information search in online tasks[END_REF]. According to a number of studies (E.g., [START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Reinke | When email use gets out of control: Understanding the relationship between personality and email overload and their impact on burnout and work engagement[END_REF], the extent of email, sent, read and received together form such a set of criterion for assessing the individuals' perception of email load.

Desired email load

According to the organizational psychology literature, individuals in organizations have certain 'desired' conditions with respect to specific organizational factors such as information load [START_REF] Frone | Chronic occupational stressors, self-focused attention, and well-being: Testing a cybernetic model of stress[END_REF] or job control [START_REF] Cummings | A Cybernetic Framework for Studying Occupational Stress[END_REF]. A 'desired' state is defined as "any state or condition the employee consciously wants" (Edwards, 1992, p. 249). We thus define 'desired email load' as the email load that the employee wants.

Literature on email load suggests that the extent to which individuals think email is helpful or desirable, influences their email use. For instance, individuals who are apprehensive towards certain communication media tend to use these media less [START_REF] Scott | Relating Computer, Communication, and Computer-Mediated Communication Apprehensions to New Communication Technology Use in the Workplace[END_REF]. This is reflected in their behavior with respect to the use of workplace communication technologies, such as in asking for corporate smartphones [START_REF] Cavazotte | Corporate smart phones: professionals' conscious engagement in escalating work connectivity[END_REF][START_REF] Matusik | Embracing or embattled by converged mobile devices? Users' experiences with a contemporary connectivity technology[END_REF][START_REF] Waller | The impact of e-mail on work-life balance[END_REF]. Similarly, individuals who consider email to be critical to their work use email more [START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF], and potentially have higher desired email load. Further, when individuals have a positive attitude towards use of email, they are thus more likely to send more emails, thereby imposing emails on their colleagues who are the receivers [START_REF] Renaud | You've Got E-Mail!' ... Shall I Deal With It Now? Electronic Mail From the Recipient's Perspective[END_REF], Mazmanian, Orlikowski, & Yates, 2005;[START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF]. This in turn may also influence the amount of emails they get back [START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF]. Based on the above, individuals' desired email load (i.e., the email load the individual wants) is, therefore, a potential predictor of email load.

Literature has also discussed that the workload stress experienced due to email, causes individuals to want to use email less email [START_REF] Pillet | Email-free collaboration: An exploratory study on the formation of new work habits among knowledge workers[END_REF]. Based on these studies, less desired email load (i.e., the email load the individual wants) is a possible reaction to workload stress caused by email.

Cybernetic theory of stress

Cybernetic theory applied to human behavior is concerned with human beings self-regulating their behaviors [START_REF] Carver | Control theory: A useful conceptual framework for personality-social, clinical, and health psychology[END_REF]. The cybernetic theory of stress [START_REF] Cummings | A Cybernetic Framework for Studying Occupational Stress[END_REF][START_REF] Edwards | A Cybernetic Theory of Stress, Coping, and Well-Being in Organizations[END_REF] suggests that individuals try to distance themselves from stressful stimuli and attempt to influence their environments so as to reduce the intensity of such stimuli. When individuals face a threatening stimulus, that is, an undesired state, they try to increase the distance between them and this undesired state. This 'distancing' is termed as the discrepancy enhancing mechanism [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF]. The undesired state becomes an 'antigoal' based on a negative perception of the threatening stimulus [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF]. In contrast, the discrepancy reducing mechanism [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF] is about trying to bring the actual and desired states closer. Therein, the desired state is the goal that the individual wants to achieve.

Increasing the distance to an undesired state (i.e., discrepancy enhancing) and reducing the distance to a new desired state (i.e., discrepancy reducing) corresponds to a coping process wherein individuals act to regulate the effects of a threatening stimulus [START_REF] Cummings | A Cybernetic Framework for Studying Occupational Stress[END_REF], Fay & Sonnentag, 2002[START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF], and embodies the primary aspects of the cybernetic theory of stress.

The cybernetic approach has been used to explain technology acceptance and avoidance behaviors. For instance, when users feel threatened by malicious use of IT, the IT threat becomes an 'anti-goal', such that they engage in discrepancy enhancing or IT use avoidance behaviors, that take them away from the threatening IT. Similarly, when users have the goal to enhance IT security, they adopt software that will protect them, thus engaging in discrepancy reducing or IT use acceptance behaviors [START_REF] Liang | Avoidance of Information Technology Threats: A Theoretical Perspective[END_REF].

Based on the above, we note that the cybernetic theory of stress can be fruitfully applied to investigate the individual's technology use behavior, especially when use of such technology is generally considered stressful, as is the case for email use. Our objective in this research is to explain how individuals regulate their use of email as a response to workplace stress. The cybernetic theory, which provides us with the conceptual structure of discrepancy enhancing and discrepancy reducing behaviors as regulatory mechanisms for dealing with stressful situations, is thus the informing basis of the research model that we introduce next.

RESEARCH MODEL

In this section, we introduce our research model and develop our hypotheses, as shown in Figure 1. We define email load as the extent of emails currently sent, read and received by the individual in a workplace context. These three email use-related activities cover most of the time spent using email, address the key aspects of email load, conceptually relate well to one another and are relevant to workload stress from email load [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF]. Desired email load refers to the extent of email that the individual wants, in the form of emails sent, received and read. Workload stress is defined as the individual's perception that his or her workload exceeds his or her capability or skills [START_REF] Cooper | Organizational stress: A review and critique of theory, research, and applications[END_REF]. Psychological strain consists of factors such as difficulty in making decisions, feeling unable to cope or having difficulty concentrating [START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF][START_REF] Kahn | Stress in organizations[END_REF]. Negative emotions consist of emotions such as nervousness or apprehension [START_REF] Cooper | Organizational stress: A review and critique of theory, research, and applications[END_REF]. Organizational commitment embodies the individual putting himself or herself out for one's organization and thinking it is worthwhile working there [START_REF] Leiter | The Impact of Interpersonal Environment on Burnout and Organizational Commitment[END_REF].

We integrate the literatures on cybernetic theory of stress, email overload, and organizational stress, to frame our hypotheses. Thus, we hypothesize that: (1) email load is positively related to workload stress (Hypothesis H1), as informed by the email overload literature; (2) workload stress is negatively related to desired email load (Hypothesis H2), as illustrated by the discrepancy enhancing mechanism from the cybernetic theory of stress; (3) desired email load is positively related to email load (Hypothesis H3), as exemplified in the discrepancy reducing mechanism from the cybernetic theory stress; and, that (4) workload stress is positively related to psychological strain (Hypothesis H4a) and negative emotions (Hypothesis H4b), and negatively related to organizational commitment (H4c), based on the organizational stress literature We next develop the logic for each hypothesis.

Hypothesis 1: Relationship between email load and workload stress (email overload mechanism)

As alluded to in Section 2.1, studies have discussed the positive relationship between email load and workload stress. Reading and sending emails are time-consuming and overloading activities that take up a large proportion of individuals' workdays [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Burgess | Email training significantly reduces email defects[END_REF][START_REF] Jackson | The cost of email interruption[END_REF][START_REF] Soucek | Coping with information overload in email communication: Evaluation of a training intervention[END_REF] because of the time spent reading and replying to a large daily volume of email [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF] and the time it

H1 (+) H2 (-) H3 (+)

Discrepancy enhancing mechanism (cybernetics) (i.e. distancing oneself from the source of stress)

Discrepancy reducing mechanism (cybernetics) (i.e. bringing the current and the desired states of email load closer)

Psychological Strain

Negative Emotions

Organizational Commitment

H4a (+) H4b (+) H4c (-)

Workload Stress

Email Load Desired Email Load

Email overload mechanism Cognitive outcome Behavioral outcome Affective outcome

takes to recover from email interruptions [START_REF] Jackson | The cost of email interruption[END_REF][START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF]. Such activities lengthen the workday. In addition to the observation that time spent receiving, reading and sending email is generally stressful per se, studies show that the longer the time spent using email, the higher the stress [START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF]. Receiving email is also mentally overloading, given that it interrupts the workflow and fragment individuals' attention [START_REF] Gupta | SIMONE: A Simulator for Interruptions and Message Overload in Network Environments[END_REF][START_REF] Jackson | The cost of email interruption[END_REF]. Thus, the sending, receiving and reading of email represents a load for the individual, both because it creates mental overload, and because it creates additional work that increases feelings of workload stress. We frame Hypothesis 1 below to exemplify the email overload mechanism (See Figure 1) at play. That is, when individuals' email load is high, it is associated with increased workload, thereby resulting in workload stress.

Hypothesis 1: Email load (that is, the extent to which the individual currently sends, receives and reads email) is positively related to workload stress.

Hypothesis 2: Relationship between workload stress, and desired email load (discrepancy enhancing mechanism)

We have discussed so far how email load can be positively related to workload stress. We now suggest how workload stress can be negatively related to desired email load. As a 'desired' state is "any state or condition the employee consciously wants" (Edwards, 1992, p. 249), desired email load thus refers to the email load that the employee wants, that is, the extent of emails sent, received or read. The idea that workload stress from email load could subsequently foster rejection and avoidance of email draws on cybernetic theory [START_REF] Carver | Control theory: A useful conceptual framework for personality-social, clinical, and health psychology[END_REF]. We recall that the discrepancy enhancing mechanism is about the individual distancing himself or herself from an undesired state, or 'anti-goal'. Applying this concept to our study, workload stress is the 'anti-goal' that employees want to avoid. Previous studies have investigated workload stress as a threatening stimulus due to which individuals are likely to employ a discrepancy enhancing mechanism (E.g., [START_REF] Frone | Chronic occupational stressors, self-focused attention, and well-being: Testing a cybernetic model of stress[END_REF]. As employees often blame email for their workload stress [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF], they may think that reducing their email load could reduce the intensity of their workload stress, and may thus desire lower email loads. The rejection of email may thus be a reaction to the perceived burden of too much email (Vidgen et al., 2011, p. 90). Furthermore, receiving, reading and sending email are time-consuming activities [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Jackson | A simple approach to improving email communication[END_REF][START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF]. One study found that reading email alone can take 29 minutes each day [START_REF] Jackson | A simple approach to improving email communication[END_REF], and another estimated that employees can lose up to 28 minutes per day being interrupted by email (i.e., receiving email) [START_REF] Gupta | SIMONE: A Simulator for Interruptions and Message Overload in Network Environments[END_REF]. Individuals are likely to want to reduce the reading, sending or receiving of email when they are already facing unmanageable deadlines and workloads. This may also explain why certain individuals would like to get rid of email altogether [START_REF] Pillet | Email-free collaboration: An exploratory study on the formation of new work habits among knowledge workers[END_REF]. Practical examples support these research findings. For example, in some organizations, "email-free" days or weeks are used to raise awareness of email-related workload stress and to reduce the desired email load of their employees [START_REF] Mark | A pace not dictated by electrons: an empirical study of work without email[END_REF]. The discrepancy enlarging mechanism [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF] is thus particularly appropriate, as it suggests that individuals may reject email when they believe it is one important cause of their workload stress. Hypothesis 2 highlights the discrepancy enhancing mechanism, as shown in Figure 1.

Hypothesis 2: Workload stress is negatively related to desired email load (that is, the extent of emails the individual want to send, receive and read).

Hypothesis 3: Relationship between desired email load and email (discrepancy reducing mechanism)

Our previous hypotheses suggest that email load will be positively related to workload stress (Hypothesis 1), which will in turn be negatively related to the desired email load (Hypothesis 2). That is, employees appraise their workload to be stressful when they appraise their email load to be too high. They react to this workload stress by desiring a lower email load.

Hypothesis 3 suggests that when employees desire a lower email load, they use less email.

Drawing from the cybernetic theory of stress, we recall that the discrepancy reducing mechanism is about trying to bring the actual and desired states closer. Applied to our study of email load, the discrepancy reducing mechanism is about employees trying to bring their actual email load as close as possible to their desired email load. Individuals who are apprehensive about emails tend to use email less [START_REF] Scott | Relating Computer, Communication, and Computer-Mediated Communication Apprehensions to New Communication Technology Use in the Workplace[END_REF], and individuals who find emails useful and desire high email load tend to use email more [START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Matusik | Embracing or embattled by converged mobile devices? Users' experiences with a contemporary connectivity technology[END_REF][START_REF] Renaud | You've Got E-Mail!' ... Shall I Deal With It Now? Electronic Mail From the Recipient's Perspective[END_REF]. Although individuals have few direct controls on the extent to which they receive and read email, they often do have control on the extent to which they send email [START_REF] Renaud | You've Got E-Mail!' ... Shall I Deal With It Now? Electronic Mail From the Recipient's Perspective[END_REF].

Individuals who do desire high email loads could reach their desired state by sending more email, and thus receive more email in response [START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF].

Practical findings support these research findings. Indeed, managers exemplify this mechanism, as they often send more emails when they need responses from others [START_REF] Byron | Carrying Too Heavy a Load? The Communication and Miscommunication of Emotion by Email[END_REF]. We know that individuals want to reach desired states in the context of IT use, and will adjust their behaviors so that their goals can be met [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF][START_REF] Liang | Avoidance of Information Technology Threats: A Theoretical Perspective[END_REF]. In the case of email use, this can work both when individuals desire either higher or lower email loads than what they have. For example, on the one hand, individuals who desire low email load can ignore emails piling in their inboxes and turn to alternative communication media [START_REF] Markus | Electronic mail as the medium of managerial choice[END_REF]. On the other hand, however, individuals who desire high email load can leave handwritten notes and voicemails to their colleagues asking to reply to their email [START_REF] Markus | Electronic mail as the medium of managerial choice[END_REF]. In both cases, individuals would try to close the distance between their actual and desired email loads. Hypothesis 3 exemplifies the discrepancy reducing mechanism, as shown in Figure 1.

Hypothesis 3: Desired email load (that is, the extent of emails the individual want to send, receive and read) is positively related to email load (that is, emails the individual currently sends, receives and reads).

Hypotheses 4: Relationship between workload stress and outcomes (stress mechanisms)

According to the stress literature, threatening stimuli such as conditions that create workload stress lead one to experience strain [START_REF] Lazarus | Theory-Based Stress Measurement[END_REF]. Strain manifests itself in a variety of different responses, often categorized in cognitive, affective and behavioral responses [START_REF] Cooper | Organizational stress: A review and critique of theory, research, and applications[END_REF].

Cognitive responses manifest in psychological outcomes such as psychological strain [START_REF] Kahn | Stress in organizations[END_REF]. Psychological strain embodies conditions such as having difficulty in making decisions, feeling unable to cope or having difficulty concentrating [START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF]. Individuals exposed to workload stress can experience these conditions, because workload stress depletes their capacity to meet job demands up to the point that they become unable to cope and recover from work [START_REF] Maslach | Understanding Burnout -New Models[END_REF], resulting in chronic fatigue and psychological ill health [START_REF] Sparks | The effects of hours of work on health: A meta-analytic review[END_REF]. We thus frame Hypothesis 4a as follows.

Hypothesis 4a: Workload stress is positively related to psychological strain.

Affective responses to stressful conditions manifest in the form of negative emotions such as anxiety, nervousness or apprehension [START_REF] Cooper | Organizational stress: A review and critique of theory, research, and applications[END_REF]. Individuals respond to workload stress by expressing such negative emotions because such stress can take an emotional toll [START_REF] Wright | Organizational behavior 'rediscovers' the role of emotional well-being[END_REF]. Indeed, workload stress is of particular relevance to negative emotions because workload stress is a negative stimuli that can lead individuals to frequently feel anxious, angry or frustrated [START_REF] Spector | Why negative affectivity should not be controlled in job stress research: Don't throw out the baby with the bath water[END_REF], and to a general state of emotional exhaustion associated with negative emotions [START_REF] Maslach | Understanding Burnout -New Models[END_REF].

Hypothesis 4b is framed to reflect this effect of workload stress on negative emotions: Hypothesis 4b: Workload stress is positively related to negative emotions.

Behavioral responses manifest in how individuals function in organizations and affect key attitudes that the individual has toward his or her job or their organization [START_REF] Cooper | Organizational stress: A review and critique of theory, research, and applications[END_REF]. Organizational commitment consists in behaviors such as being prepared to put oneself out for one's organization [START_REF] Leiter | The Impact of Interpersonal Environment on Burnout and Organizational Commitment[END_REF]. It is a notably important behavioral response to work related stress because it will determine if the individual is prepared to go the 'extra mile' at work or leave the organization or engage in presenteeism behavior (being present but contributing little added value to their job). Workload stress can negatively impact organization commitment because individuals being overloaded can develop depersonalized and less enthusiastic views of the organizations they use their energy for [START_REF] Leiter | The Impact of Interpersonal Environment on Burnout and Organizational Commitment[END_REF]. We thus frame Hypothesis 4c as follows:

Hypothesis 4c: Workload stress is negatively related to organizational commitment.

We next proceed to test our hypotheses.

METHOD

In this section, we present the details of our research design. To test our hypotheses that were informed by the literatures from cybernetic theory, email overload and organizational stress, we collected primary survey data for the purpose of this study. We describe our instruments, sample and data collection procedures. We also present the analysis of data we undertake to test our hypotheses.

Sample and data collection procedure

We collected data from a sample of full-time U.S. workers recruited from a Qualtrics panel. This panel company was selected because of the quality of their samples as reported in literature [START_REF] Brandon | Online Instrument Delivery and Participant Recruitment Services: Emerging Opportunities for Behavioral Accounting Research[END_REF]. 795 individuals accessed the online survey from a link they received by email. 67 of those were rejected as they were not full-time workers. 222 were rejected because they failed to correctly answer the attention filters, and 2 were because they answered four times quicker than the average answering time. In total, 504 complete valid responses were collected, representing a usable response rate of 63%. This sample was composed of 47.4% men and 52.6% women aged from 20 to 73 years and having a mean age of 44 years. The full sample characteristics are presented in Appendix 1.

Measures

Email load and desired email load

We measured email load and the desired email load on the basis of email sent, received and read. These three components of email load have been commonly used in email research (E.g., [START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF]. Email load was measured with three items: "At work, to what extent do you (1) receive / (2) send, forward or reply to / (3) read work e-mail?" This scale of three items was found to be reliable at α = .875. The desired email extent was measured using three similar items: "At work, to what extent would you like to (1) receive / (2) send, forward or reply to / (3) read work e-mails?" This scale of three items was found reliable at α = .871. Both these items were assessed using 7-point Likert scales ranging from "1 = Not at all" to "7 = To a very great extent" 1 .

Workload stress

Workload stress was measured using items adapted from workplace stress instruments found psychometrically reliable in previous studies [START_REF] Donald | Work environments, stress, and productivity: An examination using ASSET[END_REF][START_REF] Johnson | Organizational Screening: The ASSET Model[END_REF][START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF]. The three items assessed the extent to which participants were troubled about (1) facing unmanageable deadlines, (2) facing unmanageable workloads, and (3) lacking time to do their jobs as well as they would like. This scale was found reliable (α = .860). Each item was assessed on a 6-point Likert scale of agreement from 1="Strongly Disagree" to 6="Strongly Agree", as done in previous studies having used these items [START_REF] Donald | Work environments, stress, and productivity: An examination using ASSET[END_REF][START_REF] Faragher | A shortened stress evaluation tool (ASSET)[END_REF][START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF] and in other instruments measuring workload stress (E.g., [START_REF] Lyne | A psychometric evaluation of the Occupational Stress Indicator[END_REF]. 1 We note that our measurement of email load is different from measurement of email overload, which is what is usually done in the literature. According to the literature, email overload is measured by items such as "I find dealing with my email overwhelming" (Dabbish and Kraut, 2006, p. 434) or "I get too much email" (Hogan & Fisher, 2006, p. 1). Its measurement is thus about both the email and the cognition associated with it. We measure email load (i.e., the extent of emails sent, read and received) and workload stress separately. Our email load items do not contain cognition of workload stress, and our workload stress items do not refer to email use.

Psychological strain, organizational commitment, and negative emotions

Psychological strain was measured with three items taken from previous studies [START_REF] Donald | Work environments, stress, and productivity: An examination using ASSET[END_REF][START_REF] Johnson | Organizational Screening: The ASSET Model[END_REF][START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF]. The items asked for the frequency of occurrence over the last three months of the following: (1) difficulty in making decisions, (2) feeling unable to cope, and (3) having difficulty concentrating. The frequency was assessed on a 4-point Likert scale from 1="Never" to 4="Often". The scale was found reliable (α = .855).

Negative emotions were measured using three items taken from the PANAS scale [START_REF] Watson | The PANAS-X: Manual for the positive and negative affect schedule-expanded form[END_REF]. The scale asked the extent to which respondents generally felt (1) afraid, (2) nervous, and (3) scared. This frequency was assessed on a 5-point Likert scale ranging from 1="Very slightly or not at all" to 5="Extremely". The reliability of this scale was satisfactory (α = .856).

Organizational commitment was measured with three items developed in stress research to represent behavioral outcomes of work stressors [START_REF] Donald | Work environments, stress, and productivity: An examination using ASSET[END_REF][START_REF] Johnson | Organizational Screening: The ASSET Model[END_REF][START_REF] Johnson | The construct validity of the ASSET stress measure[END_REF]. The three items asked respondents the extent to which they (1) felt it was worthwhile to work hard for their organizations, (2) were prepared to put themselves out for their organizations if necessary, and (3) were committed to their organizations. Each item was assessed on a 6-point Likert scale of agreement from 1="Strongly Disagree" to 6="Strongly Agree", as for the aforementioned workload stress scale. As in previous studies, the scale was found reliable (α = .862).

Control variables

In order to rule out alternate factors that might influence workload stress, we controlled for a number of variables. In terms of individual characteristics, we selected the respondent's age, sex, and education level. In terms of work related variables, we selected the number of persons supervised by the respondent, and the respondent's occupation, industry and company size (See Appendix 1).

Statistical analysis

We assessed the reliability and validity of the constructs by examining the Cronbach's Alpha, Average Variance Extracted (AVE), and the inter-construct correlations. Our measurement model and hypotheses were tested using covariance-based structural equation modeling (SEM) with maximum likelihood (ML) estimation2 . To evaluate our measurement and structural models, we relied on a mix of recommended fit indices. We followed the recommended cut-off values of [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF] to assess whether our models were of acceptable fit. For each model, Chi-Square (χ 2 ) with its degrees of freedom and significance, the Comparative Fit Index (CFI), the Root Mean Square Error of Approximation (RMSEA), the Standardized Root Mean Square Residual (SRMSR), the Goodness-of-Fit index (GFI), the Adjusted Goodness-of-Fit index (AGFI), the Normed Fit Index (NFI), and the Tucker-Lewis Index (TLI) were computed. For a good fitting model, the CFI should exceed .95, the RMSEA should not exceed .06, the SRMSR should not exceed .08 [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF], the GFI, AGFI, NFI and TLI should exceed .90 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF], and the χ 2 /df should be between 1 and 5 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF]. Using these techniques and guidelines, we now present the results for the measurement and structural models.

RESULTS

Construct reliability and validity

Table 1 shows the means, standard deviations and reliability of the constructs, together with their item loadings. The reliability, measured by Cronbach's Alpha is greater than the recommended value of 0.7, for all constructs. Using [START_REF] Fornell | Structural Equation Models with Unobservable Variables and Measurement Error: Algebra and Statistics[END_REF] criteria, the convergent validity of a construct is satisfactory when (1) all of its indicators are significant and have loadings exceeding 0.7 and (2) its Average Variance Extracted (AVE) value exceeds 0.50. All items load significant at p < .001 with their standardized loading range from .715 to .921. The constructs thus demonstrated satisfactory convergent validity. The discriminant validity of the constructs is satisfactory when the square root value of their AVE is greater than their highest correlation with other constructs [START_REF] Chin | The partial least squares approach to structural equation modeling[END_REF]. This was the case for each of our constructs (See Table 2). Furthermore, we did not find common method bias to be a significant concern in our study based on the Harman's single factor test [START_REF] Podsakoff | Common method biases in behavioral research: a critical review of the literature and recommended remedies[END_REF]. .772 Facing unmanageable workloads (LOAD2)

.960 Lacking time to do your job as well as you would like (LOAD3)

.761 Psychological strain (α = .855;Mean = 1.75;Std Deviation = 0.76) Having difficulty in making decisions (STRAIN1) .793

Feeling unable to cope (STRAIN2)

.847

Having difficulty concentrating (STRAIN3)

.803 Negative emotions (α = .856; Mean = 1.76; Std Deviation = 0.85) Feeling afraid (NE1)

.883 Feeling nervous (NE2)

.756 Feeling scared (NE3)

.831 Organizational commitment (α = .862;Mean = 4.29;Std Deviation = 1.19) Feeling it is worthwhile to work hard for one's organization (ORGCOM1) .921

Being prepared to put oneself out for one's organization if necessary (ORGCOM2) .715

Being committed to one's organization (ORGCOM3) .838

Note. All items loadings were significant at p < .001. Note. Bold italic cells show the square root of AVE for each construct. Note 2. ***: p < .001 ; *: p < .05.

Structural model

The construct validities being satisfactory, the hypotheses were then examined using SEM.

The structural model presents the results of the hypotheses testing. The fit indices are presented in Table 3. The results showed that the model had a good overall fit. Table 4 and Figure 2 show that all the hypotheses were supported. Email load was positively related to workload stress (β = .229, p < .05), thereby supporting Hypothesis 1. Hypothesis 2 and 3 were also supported, as workload stress was negatively related to desired email load (β = -.386, p < .001), and as desired email load was positively related to email load (β = .764, p < .001). Finally, workload stress was positively related to both psychological strain (β = .489, p < .001) and negative emotions (β = .404, p < .001), and negatively related to organizational commitment (β = -.332, p < .001), thereby supporting Hypotheses 4a, 4b and 4c. Workload stress was not significantly related to any of the control variables. .00 CFI > .95 [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF] .98 RMSEA < .06 [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF] .04 SRMR < .08 [START_REF] Hu | Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives[END_REF] .06 GFI > .90 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF] .95 AGFI > .90 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF] .93 NFI > .90 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF] .96 TLI > .90 [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF] .98 χ 2 /df [1;5] [START_REF] Salisbury | Research Report: Better Theory Through Measurement -Developing a Scale to Capture Consensus on Appropriation[END_REF] 1.87 Note. ***: p < .001 ; *: p < .05

DISCUSSION

The purpose of this research was to investigate the relationships between email load, workload stress, and desired email load. We addressed it by investigating these relationships based on theoretical foundations from email overload literature, stress theories, and cybernetic theory, thereby unveiling new mechanisms influencing email load and desired email load. Specifically, we found that the extent of emails sent, received and read is positively related to workload stress, that workload stress is negatively related to the desired extent of emails sent, received and read, and that the desired extent of emails sent, received and read is positively related to the extent of emails sent, received and read. Furthermore, workload stress is positively related to psychological strain and negative emotions, and negatively related to organizational commitment. Our study makes a number of theoretical

Implications for research

The first theoretical contribution of this study is that it provides a novel understanding of workload stress due to email load, through the lens of the cybernetic theory. Literature has primarily investigated the relationships between email load and workload stress (i.e., email overload mechanism), but has not considered how individuals can engage in approach and avoidance behaviors regarding email use (i.e., discrepancy reducing and enhancing mechanisms). Our study examines these through the added construct of desired email load and through an examination of its antecedent and consequent effects. Specifically, we considered how discrepancy enlarging and discrepancy reducing mechanisms [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF] can be applied to understand how individuals react to workload stress from email load. One limitation of this study is that it is based on cross-sectional data. However, despite that, we find evidence that cybernetics theory can theoretically inform research that investigates stress from email load. Future studies could use longitudinal methods such as diary studies to look at how the relationships examined in this paper can develop over time. Based on our findings, we suggest that individuals possibly cope with higher workload stress due to email received, sent and read, by desiring a lower email load. They further, seek to adjust the extent of email received, sent and read, in line with their desired email load.

Second, the study provides a deeper understanding of email overload by examining the regulatory mechanisms at play between email load, desired email load and workplace stress.

Desired email load is important because it serves as a reference point for individuals to assess their email use. Stress literature has shown that desired states are core to how individuals cognitively identify the sources of their stress and the associated coping responses [START_REF] Cummings | A Cybernetic Framework for Studying Occupational Stress[END_REF][START_REF] Edwards | A Cybernetic Theory of Stress, Coping, and Well-Being in Organizations[END_REF]. While sources of stress (email load in our study) help individuals identify their undesired states, desired states (desired email load in our study) help them identify relevant coping responses [START_REF] Carver | Approach, Avoidance, and the Self-Regulation of Affect and Action[END_REF]. We thus suggest that desired email load is central to understanding both email rejection [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Mark | A pace not dictated by electrons: an empirical study of work without email[END_REF][START_REF] Pillet | Email-free collaboration: An exploratory study on the formation of new work habits among knowledge workers[END_REF] and email management practices [START_REF] Kalman | Filing, piling, and everything in between: The dynamics of E-mail inbox management[END_REF][START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF]. In spite of that it has not been examined in research on email use. While previous studies have suggested that individuals desiring to use email less suffer from greater email overload (E.g., [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF][START_REF] Sobotta | A Capacity Perspective on E-Mail Overload: How E-Mail Use Contributes to Information Overload[END_REF], they do not explain how desired email load can regulate the individual's email use when the latter leads to workload stress. By drawing on the mechanisms suggested by cybernetic theory, we conceptualize desired email load in our framework as both a potential outcome of workplace stress and a potential influencer of email load, something that current research does not examine. Interestingly, the effect size of the email load-workload stress relationship (β = .229, p < .05) is both smaller and of higher p value than that of the workload stress-desired email load relationship (β = -.386, p < .001). This finding implies that the discrepancy enhancing mechanism may be stronger than the email overload mechanism. That is, individuals might 'over-correct' for the effects of higher email load by desiring a lower email load than what might be required to retain existing levels of workload stress. In addition to these new findings, our study also supports previous findings that have shown that the more emails sent, received and read, the greater the workload stress (E.g., [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Jackson | The cost of email interruption[END_REF].

We further note that our findings have complementarity with studies that have focused on email management such as email batching and regular inbox cleaning [START_REF] Mark | Email Duration, Batching and Self-interruption: Patterns of Email Use on Productivity and Stress[END_REF][START_REF] Kalman | Filing, piling, and everything in between: The dynamics of E-mail inbox management[END_REF]. Such email management practices have potential conceptual links to our study because they could form the basis of discrepancy enhancing mechanisms (E.g., practices such as email batching could be adopted by users in order to avoid email interruptions) and discrepancy reducing mechanisms (E.g., practices such as cleaning their email inboxes regularly to keep their email load low). Future research could examine these links. We further note that the cybernetic approach may be helpful for understanding, in a similar way, the stressful effects of other characteristics of IT use such as connectivity and multitasking. Future research can study discrepancy-enhancing and discrepancy-reducing processes associated with these aspects of IT as well and identify implications for other stressors such as techno-overload and techno-invasion [START_REF] Tarafdar | The Impact of Technostress on Role Stress and Productivity[END_REF].

Third, in examining the relationship between workload stress, and psychological strain, negative emotions and organizational commitment, we show that these negative effects can arise directly and indirectly from email load. Literature has often considered email overload by itself (E.g., [START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF][START_REF] Dabbish | Email overload at work: an analysis of factors associated with email strain[END_REF][START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF] or as an antecedent of work overload (E.g., [START_REF] Barley | E-mail as a Source and Symbol of Stress[END_REF][START_REF] Taylor | E-mail at work: A cause for concern? The implications of the new communication technologies for health, wellbeing and productivity at work[END_REF], burnout (E.g., [START_REF] Reinke | When email use gets out of control: Understanding the relationship between personality and email overload and their impact on burnout and work engagement[END_REF]) and emotional exhaustion (E.g., [START_REF] Brown | E-mail in the Workplace: The Role of Stress Appraisals and Normative Response Pressure in the Relationship Between E-mail Stressors and Employee Strain[END_REF].

We enrich this literature by conceptualizing and validating workload stress as well as the three types of strains as potential effects of email load. In doing so, we also create theoretical links between the literatures on email use and concepts from organizational stress. To the best of our knowledge, such integration between two literatures is rare.

Fourth, we note here that the relationship linking desired email load to actual email load did not take into consideration the role of control the individual has over his or her email load [START_REF] Hair | The influence of self-esteem and locus of control on perceived email-related stress[END_REF]. Indeed, employees might not have entire control over their email load. Desiring one's email load to decrease might not be enough to decrease one's email load. For instance, literature has discussed the imbalance in control over email load between managers and subordinates (E.g., [START_REF] Derks | Smartphone use and work-home interference: The moderating role of social norms and employee work engagement[END_REF] or between senders and receivers (E.g., [START_REF] Burgess | Email training significantly reduces email defects[END_REF][START_REF] Hiltz | Structuring Computer-mediated Communication Systems to Avoid Information Overload[END_REF]. We note, however, that controlling for the number of persons under one's supervisions and for one's occupation did not influence our results, meaning that our model held for both managers and non-managers.

Future research could study the effect of control over email load (E.g., [START_REF] Hair | The influence of self-esteem and locus of control on perceived email-related stress[END_REF] on the relationships examined in this paper.

Fifth, this study contributes to the technostress literature in the following ways. Through the cybernetic theory of stress, we introduce the concept of regulation as a means of coping with stress from the use of email. In our study, we examined regulation as embodied in changes in desired email load. Future research can examine other means of regulation as ways to cope with technostress from other types of applications [START_REF] Tarafdar | The technostress trifectatechno eustress, techno distress and design: An agenda for research[END_REF]. Similar to our findings about desired email load, desired technology use or attitudes towards technology may act as technostress coping responses and lead to IS use related behaviors (e.g., IS approach and avoidance).

Implications for practice

In terms of implications for practice, we empirically demonstrated the existence of discrepancy enlarging and discrepancy reducing mechanisms. On the one hand, employees may want to distance themselves from email when they experience high levels of workload stress. It may therefore be risky to promote a culture encouraging the use of email [START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF] in organizations with already high levels of workload stress. On the other hand, employees want to send, receive and read emails to the extent they actually desire to do so. It may thus be equally risky to reduce or ban emails [START_REF] Pillet | Email-free collaboration: An exploratory study on the formation of new work habits among knowledge workers[END_REF] when employees consider email to be an important medium [START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF]. Individuals' desired email load should also be respected by those who have control over their email load. Senders with managerial responsibilities have a particular responsibility to consider the email they send to their subordinates [START_REF] Derks | Smartphone use and work-home interference: The moderating role of social norms and employee work engagement[END_REF], given their hierarchical power over them. Similarly, when individuals send email, they should consider the fact that the receivers' extent of emails received and read may increase. Adapting one's email use to others' desired email loads may however be difficult in organizations that already have strong cultures either promoting [START_REF] Sumecki | Email overload: Exploring the moderating role of the perception of email as a 'business critical' tool[END_REF] or discouraging [START_REF] Pillet | Email-free collaboration: An exploratory study on the formation of new work habits among knowledge workers[END_REF] email use and, thereby, limiting individual opportunities to self-adjust. Finally, we have shown that workload stress can be associated with increased psychological strain and negative emotions, and decreased organizational commitment. The email use regulating mechanisms we have unveiled should thus matter to organizations, because through these relationships, they matter to the individuals' workplace well-being.

To conclude, given that email is the most widely used medium for electronic communication in organizations, it is important to understand the relationships among employees' email load, workload stress and desired email load. In this paper, we show that workload stress can be influenced by email load and in turn influence desired email load. The relationships investigated in this paper can form the basis of future studies that examine how individuals cope with workload stress from their use of organizational email. This article is © Emerald Group Publishing and permission has been granted for this version to appear here (http://www.jfstich.com/). Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited.

Appendix 2. Covariance Matrix (N = 504). Note 1. EL: Email load (EL_receive refers to the extent of emails received, EL_send refers to the extent of emails sent, and EL_read refers to the extent of emails read). Note 2. DEL: Desired email load (DEL_receive refers to the desired extent of emails received, DEL_send refers to the desired extent of emails sent, and DEL_read refers to the desired extent of emails read). Note 3. LOAD: Workload stress (LOAD1, LOAD2 and LOAD3 refer to the three items of workload stress). Note 4. STRAIN: Psychological strain (STRAIN1, STRAIN2 and STRAIN3 refer to the three items of psychological strain). Note 5. NE: Negative emotions (NE1, NE2 and NE3 refer to the three items of negative emotions). Note 6. ORGCOM: Organizational commitment (ORGCOM1, ORGCOM2 and ORGCOM3 refer to the three items of organizational commitment).

Figure 1 .

 1 Figure 1. Research Model.

Figure 2 .

 2 Figure 2. Structural Model (N = 504).

  up avenues for further research and has implications for practice, as we describe below.

Table 1 .

 1 Item Loadings and Significance Levels for Constructs (N = 504).

	Items descriptions

Table 2 .

 2 Construct Correlations and Average Variance Extracted

		1.	2.	3.	4.	5.	6.
	1. Email load	0.84
	2. Desired email load	0.80***	0.83
	3. Workload stress	-0.07	-0.22*** 0.83
	4. Psychological strain	0.01	-0.09	0.49*** 0.82
	5. Negative emotions	-0.06	-0.12*	0.40*** 0.71*** 0.82
	6. Organizational commitment 0.17***	0.32*** -0.33*** -0.35*** -0.28*** 0.83

Table 3 .

 3 Fit Indices for the Structural Model (N = 504).

	Fit indices	Recommended values	Structural model
	χ 2		229.00
	d.f.		123
	Sig. (p value)

Table 4 .

 4 Hypotheses testing (N = 504).

	Hypotheses

This article is © Emerald Group Publishing and permission has been granted for this version to appear here (http://www.jfstich.com/). Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited.

The analyses were done using the R software with the package lavaan[START_REF] Rosseel | lavaan: An R package for structural equation modeling[END_REF] version 0.5-20 for SEM and semTools[START_REF] Pornprasertmanit | semTools: Useful tools for structural equation modeling. R Package Available on CRAN[END_REF] version 0.4-11 for the calculations of Cronbach's Alpha and Average Variance Extracted (AVE). The covariance matrix is reported in Appendix 2 and the R syntax is reported in Appendix

APPENDICES

covariance_matrix <-getCov(lower_matrix,names = c("EL_receive", "EL_send", "EL_read", "DEL_receive", "DEL_send" , "DEL_read", "LOAD1", "LOAD2", "LOAD3", "STRAIN1", "STRAIN2", "STRAIN3", "NE1", "NE2", "NE3", "ORGCOM1", "ORGCOM2", "ORGCOM3")) fitMeasures(fit, c("cfi", "rmsea", "srmr", "gfi", "agfi", "nfi", "tli"))

# Optional: Plot the model using the semPlot package # install.package("semPlot") # library(semPlot) # semPaths(fit, what="path", whatLabels="std", edge.label.cex=1, sizeLat=10, sizeMan=8, reorder=FALSE, nCharNodes=15, curvePivot = TRUE, residuals=FALSE, rotation=2, layout="tree2")