Does supportive supervisor complements the effect of ethical leadership on employee engagement?

Abstract The purpose of the study is to examine the effect of perceived supervisor support on the relationship between ethical leadership and employee engagement through organisational commitment in eastern culture. The study uses survey data from 389 employees of information technology sector in Pakistan. To study the relationship between the variables, linear regression, and Preacher & Hayes (2004) PROCESS techniques are used. The results of the study show that ethical leadership relates to employee engagement and organisational commitment. Organisational commitment mediates the relationship between ethical leadership and employee engagement. Perceived supervisor support moderates the relationship such that when perceived supervisor support is high, the effect of ethical leadership on employee engagement through organisational commitment is stronger. The results show that the positive perception of the supervisor complements the effect of ethical leadership on employee engagement through organisational commitment. Ethical leadership contributes towards the development and sustenance of organisational commitment and engagement among the employees. Drawing on social exchange theory, this study contributes to the organisational behaviour literature by studying the complementing effect of perceived supervisor support on the relationship between ethical leadership and employee engagement. An area that needs due attention.


PUBLIC INTEREST STATEMENT
An organisation's workforce must be engaged to maintain competitive advantage. Leadership is critical in energising and motivating employees, as well as increasing their commitment and performance. Sustaining a supportive supervisory relationship improves employee job satisfaction and engagement. In this backdrop, the study examines the influence of supportive supervision on the relationship between ethical leadership and employee engagement through employee commitment to the organisation. This study highlights the benefit of having supportive vis-àvis less supportive supervisors. It indicates that supportive supervisors complement the effect of leadership and helps maintain high engagement among the employees. That provides competitive edge to the organisation. The novelty of this research is that it is the first study where perceived supervisor support is used as a moderator in the relationship between ethical leadership and employee engagement through organizational commitment.

Introduction
Employee engagement is an extensively researched construct (Ababneh et al., 2019). It captures zeal and dedication with which employees perform their work role (Schaufeli & Bakker, 2004). It positively relates to organisational efficiency, inventiveness, and competitiveness (Welch, 2011) and negatively relates to employee withdrawal behaviour, low organisational commitment, and reduced competitiveness (Hunsaker & Jeong, 2020;Saks & Gruman, 2014). Gallup's survey reports that about two-third of the workforce is disengaged (Harter, 2016;Rigby & Ryan, 2018). Absence of employee engagement in the workforce's bulk is a serious concern for the business enterprises. Schaufeli et al. (2001) defines employee engagement as a cognitively pleasing disposition towards work, characterised by 'vigour, dedication, and absorption" p. 74). Vigour refers to an employee's tenacity to perform a job. Dedication represents his/her involvement in the job. Absorption is being immersed in the job. Christian et al. (2011), Newman et al. (2011), and Ababneh et al. (2019 link the notion of employee engagement with the perception of organisational commitment, but the two concepts have distinct constructs (Kahn, 1990;Macey & Schneider, 2008;Saks, 2006;Welch, 2011). Employee engagement refers to work passion (Newman et al., 2011), while organisational commitment represents the relationship between an employee and his/her organisation that inhibits the employee to leave the organisation (Allen & Meyer, 1996).
Literature shows that ethical leadership (Engelbrecht et al., 2017;Özsungur, 2019), organisational commitment (Hunsaker & Jeong, 2020;Kim et al., 2017) and supervisor support (Farndale, 2017;Sarti, 2014) augments employee engagement. Ahmad and Gao (2018) note that study of the effect of ethical leadership on employee engagement in eastern cultures has received little attention. Several researchers have used organisational commitment as a mediator with ethical leadership with different dependent variables (e.g., Asif et al., 2020;Lee et al., 2019;Yang & Wei, 2018) but a few studies can be found where the outcome variable is employee engagement (e.g., Asif et al., 2019). There is scarcity of research where scholars used perceived supervisor support as a moderator with ethical leadership. The only exception is, Tu et al. (2019), who used perceived supervisor support as a moderator in the relationship between ethical leadership and creativity. This is the first paper to study that to what extent perceived supervisor support complements the effect of ethical leadership on employee engagement. That will highlight the importance of a supportive supervisor in the work edifice. To address this gap, the paper examines the relationship between ethical leadership and employee engagement through organisational commitment with perceived supervisor support as moderator using social exchange theory (Blau, 1964). Research model is at Figure 1. This study makes several contributions. First, recognising the effect of culture on leaders' behaviour (Dorfman et al., 2012), this study examines the relationship between ethical leadership and employee engagement in eastern culture. An area that received little attention (Ahmad & Gao, 2018). Second, the study highlights the role of supervisor in the relationship between ethical leadership and outcome variables using moderated mediation analysis. Third, the study enriches literature on mediating effect by organisational commitment in the relationship between ethical leadership and employee engagement. Finally, the study addresses the need to increase our understanding of the mechanism used by ethical leaders to influence followers (Ahmad & Gao, 2018;Babalola et al., 2019;Neves & Story, 2015). In this context, this study highlights the mechanism used by ethical leaders while remaining within the ambit of social exchange theory.

Ethical leadership
The concept of ethical leadership gained currency because of unethical conduct by the executives of leading business enterprises (Riggio et al., 2010;Thiel et al., 2018). Riggio et al. (2010) observed that the notion of ethical leadership can be approached in context with individual attributes or traits and the behavioural aspects. Subscribing to individual attributes or virtues, Riggio et al. (2010) defines ethical leader, as the one who conforms to four import qualities: "prudence, courage, temperance, and justice" (p. 235). Prudence implies careful decision-making to avoid risk. That is to consider moral values and consequences of the decision (Stouten et al., 2012). Courage is the ability of an ethical leader to face resistance while acting ethically. Temperance implies exercising restraint from getting indulged in selfish and covetous excesses. Justice is being fair. Brown et al. (2005) defined ethical leaders as the one who display morally correct behaviour as an individual and while interacting with others. Ethical leaders promote such behaviours while interacting with their followers through reward and punishment and by their decisions. That corresponds to the behavioural approach (Stouten et al., 2012). Treviño et al. (2000) describes ethical leadership in terms of "moral person" and "moral manager." As a moral person, the ethical leader must be, "honest, trustworthy, caring, open to input, principled, and respectful of others" (Yukhymenko-Lescroart et al., 2015, p. 38). They show moral attributes and act as a role model for the followers (Bavik et al., 2017;Stouten et al., 2012). Followers observe and emulate their ethical values. They internalise the moral values of their managers and develop their own moral identity (Rupp et al., 2013). In the process, followers develop a genuine concern for others (Schaubroeck et al., 2012). To instil moral values in the followers, managers make them accountable to act appropriately (Brown & Treviño, 2006). As an external regulatory instrument, moral managers enact and execute policies to align employee behaviour with the ethical and organisational norms (Bavik et al., 2017). It is through these processes' the moral manages mould ethical behaviour of their follower (Thiel et al., 2018). Ethical leadership relates to several outcomes, e.g., organisational performance (Brown & Treviño, 2006;Riggio et al., 2010), inclusion climate (Yukhymenko-Lescroart et al., 2015), performance, organisational citizenship behaviour, and reduced production deviance (Thiel et al., 2018), organisational concern (Wingate et al., 2019), employee work engagement (Qin et al., 2014) and so on.

Social exchange theory
Social Exchange Theory (Blau, 1964) provides a conceptual basis to understand the mechanism through which ethical leaders infuse engagement among the employees. Social exchange theory postulates that responsibilities and debts are generated between two dependent parties because of a series of interactions between them (Saks, 2006). It is one of the most important theory to understand workplace behaviour (Cropanzano & Mitchell, 2005). Social exchange theory illustrates that if reciprocity is maintained, it fosters trust, loyalty, and commitment in the relationship (Cropanzano & Mitchell, 2005). It generates mutual obligations through a series of interactions in an interdependent relationship (Blau, 1964). These interactions generate unspecified mutual obligations (Blau, 1964) involving future expectations (Gouldern, 1960). Trust is central to this relationship (Musgrove et al., 2014). Blau (1964) maintains that trust is generated through consistent "discharge of obligations." Schaubroeck et al. (2013) note that trust reduces uncertainty in relationships, that improves the quality of social exchanges and hence the working environment. This theory is often used by the researchers (e.g., Charoensap et al., 2018;Yasir & Rasli, 2018) to explain the process through which ethical leaders influence their followers.

Employee engagement
Employee engagement is a principal issue in human resource management (Borkowska & Czerw, 2017). Attridge (2009) and Schaufeli and Bakker (2004) note that Kahn (1990) is the first scholar who theorized engagement. Kahn (1990) defines engagement as employee attachment with their work, such that they express themselves physically, psychologically, and intellectually through the work. Kahn (1990) conceptualizes engagement as a relationship between employee and his job, wherein the job provides a platform for self-expression, that is, creativity. For the purpose, the employee uses their physical and mental abilities. Schaufeli et al. (2001) defines employee engagement as cognitively pleasing disposition towards work distinguished by "vigour, dedication, and absorption" (p. 74). Vigour refers to an employee's hard work, persistence, and resilience. Dedication represents employee involvement in the job such that the job becomes a source of pride and motivation. Absorption means an employee's involvement in the jobs to the extent that he or she loses track of time (Bakker et al., 2008;Del Líbano et al., 2012). Employee engagement positively relates to several outcomes, for example, distributive, and interactional justice (Alvi & Abbasi, 2012), organisational commitment (Lin et al., 2019), employee intrapreneurial behaviour, and personal resources (Gawke et al., 2017), and negatively relates to employee turnover intention (Malik & Khalid, 2016), voluntary absence (Shantz & Alfes, 2014), and diversity-oriented HR practices (Luu et al., 2019).
Social exchange theory is one of the important theories that is used to understand how employee engagement takes effect (Oades et al., 2017). Reciprocity is central to social exchange theory (Blau, 1964). Subscribing to the notion of reciprocity, ethical leaders create a collaborative model of interaction with their followers. They maintain positive relation with the employees, listen to them, and guard their interests (Brown et al., 2005) and take fair decisions. In the process, they maintain an honest exchange relationship with the employees (Bedi et al., 2016). When employees are treated justly, they reciprocate and exhibit higher commitment (Mahsud et al., 2010). Walumbwa et al. (2012) observe that as a response to the positivity exhibited by ethical leaders the followers respond by performing well on the job. This leads to the hypothesis that: Hypothesis 1: Ethical leadership positively relates to employee engagement.

Organisational commitment
Organisational commitment embodies attachment between the employee and the organisation (Lambert et al., 2019). Yahaya and Ebrahim (2016) note that Organisational commitment is defined in different ways. Citing, Porter and Smith (1970), Mowday et al. (1979) define organisational commitment as degree of an individual's affiliation with and taking part in the activities of the organisation. Mowday et al. (1979) note that this definition reflects employee's conviction in the goals and values of the organisation, readiness to put in efforts on behalf of the organisation and desire to keep the membership of the organisation. Allen and Meyer (1990) define organisational commitment as, attachment between an employee and his organisation that reduces the possibility of employee turnover. Allen and Meyer (1990) underscores that for a better understanding of employee-organisation link and turnover intention, it would be appropriate to study the three dimensions of organisational commitment, i.e., affective commitment that encapsulates employee emotional affection with the organisation (Imamoglu et al., 2019), continuance commitment is the employee preference to continue with the job based on cost-benefit analysis (Meyer & Herscovitch, 2001) and normative commitment implies continuing with the job out of sense of responsibility or gratitude (Meyer & Herscovitch, 2001). Uraon (2018) note that these dimensions measure three different aspects of organisational commitment having a distinct effect on the efficacy of employees and the organisation. Organisational commitment is positively associated to several outcomes like employee devotion to work (Yahaya & Ebrahim, 2016), work proficiency (Saadeh & Suifan, 2019), job performance (Hussain et al., 2019), employee performance (Hendri, 2019), job satisfaction (Lin et al., 2019), work engagement, (Zhang et al., 2015) and so on. It is negatively related to turnover intention (Rawashdeh & Tamimi, 2019), and absenteeism (Samad & Yusuf, 2012).
Ethical leaders treat their followers in a positive manner. They exhibit loving behaviour and guard their best interests (Brown et al., 2005), listens to them, are fair in their decisions, and enforce ethical standards. Bedi et al. (2016) note that ethical leaders maintain a quality exchange relationship with their followers through positive behaviours (Brown & Treviño, 2006). Mahsud et al. (2010) observes that the followers reciprocate fair treatment extended to them by being respectful, loyal, and committed. The ethical leadership is positively related to organisational commitment (Addai et al., 2019;Aryati et al., 2018), and employee engagement (Sarwar et al., 2020;Zappalà & Toscano, 2020). While organisational commitment is positively related to employee engagement (Adi & Fithriana, 2020;Putri & Setianan, 2019). These earlier studies reflect on direct relationship between ethical leadership and organisational commitment and role of organisational commitment as mediator (Baron & Kenny, 1986). This leads to the following hypotheses: Hypothesis 2: Ethical leadership positively relates to organisational commitment.
Hypothesis 3: Organisational commitment mediates the relationship between ethical leadership and employee engagement.

Perceived supervisor support as moderator
Perceived supervisor support underlines employee perception that their supervisor "values their contributions and cares about their well-being" (Gonzalez-Morales et al., 2018, p. 152). They identify four basic elements that reflect supervisor support, that is, "benevolence, sincerity, fairness, and experiential processing". Benevolence implies acknowledging extra efforts put in by the employees, accepting and using mistakes for learning, providing necessary training to the employees, and compensating for the mistreatment by the customers. It reflects sincerity when supervisors fulfil their promises, treat employees with respect, give honest feedback on their performance, give clear directions, and advise them on how to improve their performance (Eisenberger & Stinglhamber, 2011). Uniform and unbiased enforcement of policies represent fairness. Fairness also includes listening to the employees and providing them opportunity for correction (DeConinck, 2010). Experiential processing means handling the information responsibly to avoid knee-jerk reactions (Good et al., 2016). That provides the supervisor an opportunity to study the situation in an unbiased manner. Such behaviour by the supervisor in a stressful environment leads to a stronger perception of supervisor support. Perceived supervisor support positively relates to trust in the supervisor (Akram et al., 2018), job autonomy and job security (Alvi et al., 2014) affective and normative commitment (Bashir & Long, 2015), task performance (Afzal et al., 2019), affective commitment, normative commitment, and motivation to learn and develop (Mylona & Mihail, 2019). This discussion leads to the resultant hypothesis to study moderation by perceived supervisor support in the relationship between ethical leadership and employee engagement through organisational commitment.
Hypothesis 4: Perceived supervisor support moderates the relationship between ethical leadership and employee engagement through organisational commitment such that this relationship is stronger when perceived supervisor support is high than low.

Sample and procedure
The data for the study is collected through a field survey conducted among the employees of information technology companies located in Rawalpindi-Islamabad region of Pakistan. After necessary coordination with the management of respective information technology companies' 600 questionnaires are distributed among the employees for the cross-sectional survey. A covering letter with the questionnaire explained the purpose of the survey. To assure privacy of the respondents, their responses are collected by the survey team. At the end of the survey, 389 usable responses are available. That accounts for 64.83% response rate. Of these participants, 82.5% are male, and 17.5% are female. The average age of the respondents is 28.03 years. The average experience of the participants is about six years. Table 1 presents demographic information of the participants.

Measures
Self-reported questionnaire in English is used to collect the data for the study. Most of the individuals working in IT industry of Pakistan can speak and understand English; however, to facilitate less educates individuals, Urdu translation of the questions is added to the questions in English. No complaint is received about the understanding of the questionnaire. To tap responses, a five-point Likert scale (1 = strongly disagree to 5 = strongly agree) is used.  Brown et al. (2005) is used. It is a popular measure of ethical leadership (Bedi et al., 2016). Sample items include "My leader listens to what employees have to say" and "My leader discusses business ethics or values with employees." The Cronbach's alpha for this measure in the current study is 0.91.
Organisational Commitment: A 9 items, shorter version of unidimensional Organisational Commitment Questionnaire by Mowday et al. (1979) is used in this study. The use of this shorter version of the questionnaire is common among the scholars (e.g., Ozmen, 2019;Rawashdeh & Tamimi, 2019;Talukder, 2019). Sample items include "I am proud to tell others that I am part of this organisation" and "I really care about the fate of this organisation." The reliability of the scale in the present study is 0.90.
Employee Engagement: Christian et al. (2011) observes that Utrecht Work Engagement Scale (UWES) is the most popular scale used by the researchers to measure work engagement. This study uses the nine items (shorter version of UWES) to measure employee engagement (e.g., Albrecht et al., 2018;Jha et al., 2019;Kaya & Karatepe, 2020). Sample items include "At my work, I feel bursting with energy" and "My job inspires me." The reliability of the scale in the current study is 0.90.

Perceived Supervisor Support:
Perceived organisational support questionnaire developed by Eisenberger et al. (1986) and as modified by Rhoades et al. (2001) by replacing word organisation with the supervisor is widely in use to measure perceived supervisor support (e.g., Afzal et al., 2019;Mylona & Mihail, 2019). This study uses the questionnaire as modified by Rhoades et al. (2001) to measure perceived supervisor support. Sample items included "My supervisor cares about my opinions" and "My supervisor strongly considers my goals and values." In this study, the reliability of the scale is 0.85.

Data analysis
For data analysis, SPSS AMOS version 20 and Preacher & Hayes (2004) PROCESS macro for SPSS is used. Following Kline's (2011) advise, Confirmatory Factor Analysis (CFA) is used to assess the model. For a good model fit, Kline (2011) suggests that the value of χ 2 /df should be less than 3, and the values of GFI, CFI, NFI, and TLI should be more than 0.90, whereas the value of RMSEA should be less than 0.08. CFA of the data show that χ 2 /df = 1.61, GFI = .90, CFI = .96, NFI = .90, TLI = .96 and RMSEA = 0.04. These values are within the specified limits and show a good fit of the model to the data.
Internal consistency reliability is checked using Cronbach's alpha. Hair et al. (2011) note that the Cronbach's alpha should be higher than 0.70; however, in the case of exploratory research, values from 0.60 to 0.70 may be accepted. In this study, the values of Cronbach's alpha range from 0.85 to 0.91 (Table 2), which indicates excellent consistency. Convergent validity and discriminant validity is established using Composite Reliability (C.R.) and Average Variance Extracted (AVE). The acceptable values for C.R. and AVE should be 0.70 and 0.50, respectively (Joseph F Hair et al., 2010). In this study, the values of C.R. and AVE are higher than the threshold level (Table 2). That shows a good convergent validity. For a good discriminant validity, the value of the square root of AVE should be more than the value of correlation coefficients of the variables in the Pearson correlation matrix (Joseph F Hair et al., 2010). In this study, the values of the square root of AVE are greater than the values of the correlation coefficients of the Pearson correlation matrix (Table 3). That reflects on satisfactory discriminant validity.
Harman's one-factor analysis is used to check for common method bias (Podsakoff et al., 2003). Single factor accounts for 31.16% variance, which is less than the 50% threshold level. To further confirm the finding, CFA of the one-factor model is performed. The results show a poor model fit (χ 2 /df = 6.92, GFI = .51, CFI = .59, NFI = .55, TLI = .56 and RMSEA = 0.124). The findings show that the possibility of common method variance in the data is minimal.

Control variables
Control variables are identified using one-way ANOVA. Education is controlled for organisational commitment, while gender is controlled for employee engagement.

Results
Means, SD, Pearson bivariate correlations, and the square root of AVE are shown in Table 3. The correlation reveals that ethical leadership is positively relates to employee engagement (r = .44, p < .01), organisational commitment (r = .54, p < .01), and perceived supervisor support (r = .56, p < .01). Values of the square root of AVE, as shown in parentheses, are greater than the correlation valves. That shows a satisfactory discriminant validity among the variables.  To test the hypotheses, the variables are mean centred. The results at Table 3 (correlations) and Table 4 (regression coefficients) show a direct relationship of ethical leadership with organisational commitment and employee engagement. In this, ethical leadership is significantly and positively related to employee engagement (β = 0.44, p < .001), and organisational commitment (β = 0.54, p < .001). That supports hypotheses 1 and 2.
Mediation is tested using Preacher & Hayes (2004) PROCESS technique. Table 5 presents the results for the mediation hypothesis. The two-tailed test with normal distribution indicates that the mediation by organisational commitment is significant for employee engagement (Sobel effect = 0.16, z = 5.82, p < .001). The results of the Sobel test with bias corrected 5000 bootstrap sample and with 95% Confidence Interval (CI) show non-zero values for employee engagement (0.11, 0.23). Thereby the hypothesis 3 is supported.
Lastly, Table 6 presents the findings of moderated mediation effects of perceived supervisor support on the relationship between ethical leadership and employee engagement through organisational commitment. The conditional indirect effect of ethical leadership on employee engagement is analysed at three different values of perceived supervisor support, i.e., the mean (.00), +1 SD (1.47), and −1 SD (−1.47). The indirect effect of ethical leadership on employee engagement through organisational commitment exists on low (0.062, 0.176), medium (0.088, 0.206) and high (0.101, 0.256) level of perceived supervisor support. However, at high level of perceived supervisor support, the effect of ethical leadership on employee engagement through organisational commitment is more pronounced. That renders support to hypothesis 4.

Discussion
The main objective of the study is to investigate the effect of perceived supervisor support on the performance of ethical leadership in eastern culture. For the study, data is collected from the employees of IT companies operating in Pakistan. The results show that ethical leadership is positively and significantly related to employee engagement and organisational commitment. Organisational commitment mediates the relationship between ethical leadership and employee engagement. Perceived supervisor support moderates the relationship such that when it is high the effect of ethical leadership is stronger on employee engagement through organisational commitment.

Theoretical implications
The study contributes to the literature on a number of accounts. First, it examens the relationship between ethical leadership and employee engagement in non-western culture. An area that received limited attention (Chughtai et al., 2015;Demirtas, 2013). Findings of this study suggest that ethical leadership enhances employee engagement. This finding is in line with the earlier work done on the subject by Demirtas (2013) and Ahmad and Gao (2018). Second, the study uses organisational commitment as mediator in the relationship between ethical leadership and employee engagement. The findings of the study indicate that the organisational commitment mediates the relationship. The finding complements the work of Asif et al. (2019) as they studied the effect of ethical leadership on work engagement through affective commitment in China. Third, the most important contribution of the study is that it highlights the role of supervisor support as moderator. Perceived supervisor support moderates the relationship between ethical leadership and employee engagement through organisational commitment such that the effect of ethical leadership on employee engagement is stronger when perceived supervisor support is high. That indicates that supportive supervisor complements the effect of ethical leadership. In all probability, this study is the first that examines the effect of perceived supervisor support on the relationship between ethical leadership and employee engagement through organisational commitment.

Practical implications
The study has a number of practical implications for the management. First, this study confirms the effectiveness of ethical leadership in collectivist and high-power distance culture of Pakistan (Hofstede, 1980). That underscores the adoption of ethical leadership style in this culture will enhance employee engagement. Second, the study shows that ethical leadership augments both organisational commitment and employee engagement. The study also demonstrates that organisational commitment mediates the relationship between ethical leadership and employee engagement implying that organisations should work to enhance the commitment of the employees for their better engagement at work. Third, perceived supervisor support complements the effect of ethical leadership on employee engagement. This highlights that perceived supervisor support plays an important role in optimizing employee engagement. Organisations need to develop supportive culture among the supervisors to ensure better performance by the employees. Finally, the study demonstrates that positivity exhibited by the ethical leaders and the supervisor's results into increased engagement by the employees. Positive reciprocity underscores the mechanism that plays a cardinal role in inducing engagement among the employees.

Limitations and future research
The major limitation of this study is that the data is collected using self-reported questionnaires from a single source. Although, Harman's one-factor analysis (Podsakoff et al., 2003) and CFA of the one-factor model is done to check for common method bias. To preclude the possibility of common method bias, future researchers may resort to time-series data collection. Second, the data is collected from the employees of IT sector of Pakistan. That limits the generalizability of the findings of the study. Future researchers can conduct multi-industry and multi-cultural study for better generalizability.