The Importance of Leader Integrity on Family Restaurant Employees’ Engagement and Organizational Citizenship Behaviors: Exploring Sustainability of Employees’ Generational Differences

The purpose of this study is to investigate how foodservice employees’ perceptions of their leader’s integrity affect their work engagement and organizational citizenship behaviors, with the aim of moderating empirical evidence of generational differences. This study was administered to 218 foodservice employees using a self-administered questionnaire. The validity and reliability of the measured items were reviewed using a confirmatory factor analysis (CFA), and they were verified using structural equation modeling (SEM). The study results showed that leader integrity had a significant positive effect on employees’ work engagement, and organizational citizenship behaviors, while employee engagement induced by leader integrity increased organizational citizenship behaviors (OCBs). Also, the results found that the effects of leader integrity on OCBs were stronger for Generation Y workers than for Generation X workers. Limitations and future research directions are also discussed.


Introduction
Due to intensifying competition and transparent outcomes, foodservice companies rely on their employees to provide leadership and customer service [1], yet they have difficulty recruiting and retaining highly qualified employees because of low wages, long working hours, high turnover rates, and poor conditions of employment [2]. This is why it is necessary to investigate the work attitudes and behaviors that enable these companies to keep service employees engaged in their organizations and encourage these workers to behave with genuine positivity. Researchers of organizational behavior have long been interested in exploring how an organization's members' perceptions of their leaders affect their work-related thoughts and behaviors [3]. Wide-ranging leadership theories have been advanced to explain how managers retain highly qualified employees and motivate an organization's members, and a variety of studies have demonstrated the effectiveness of leadership in this regard [4,5]. Expanding awareness of a leader's integrity has been suggested as a method for establishing and maintaining confidence between leaders and an organization's members [6]. The integrity of a leader relates to how well they keep their promises and how much the employees trust them to do so, and this confidence can serve as a motive for employees to trust their leaders [7]. In regards to the leader's benefits from complying with moral and ethical standards, the concept of leadership integrity is distinct from the Leader-Member Exchange (LMX) theory that explains the superior-subordinate relationship based on social exchange theory [8]. In a frame analysis aimed at forecasting the results of human resources management practices, Gould-Williams and Davies [9] stated that employees' trust in their leaders is highly important for creating employees' enthusiasm, motivating the employees, and retaining them.
Spector and Fox [10] argued that when an organization and its leaders highly prioritize developing a good ethical and moral climate, the long-term well-being of both individuals and the organization is improved. Workers thus feel happy and become productive laborers, demonstrating that the importance of a fair climate and leaders' behaviors in an organization cannot be overemphasized. A recent meta-analysis also revealed that employees' assessments of the integrity of their leaders was clearly associated with the satisfaction, commitment, confidence, and the performance of the employees [11]. Despite the importance of integrity, however, little is currently known about how leader integrity is related to secondary responses-a connection that requires in-depth understanding, because employees in the foodservice industry in particular have significant social interactions with their leaders [12]. Studies of the relationship between leader integrity and an organization's members have, to date, mainly been conducted in terms of business administration. According to the theory of cohorts, common values and opinions can be formed among the people in a cohort by experiencing and growing from specific events at the same time and through common levels of emotional development [13]. Managers in an organization must therefore learn the values and patterns of behavior of members of each generation through trial and error to effectively manage them [14]. According to Porath [15], a lack of proper communication due to differences between generations can cause an increase in interpersonal interaction problems within an organization and these issues require responses at the organizational level [16]. This study therefore examines the roles of moderate based on employees' generations. In Korea, most workers within organizations are currently from Generation X, while Generation Y is now entering the labor market; together, they comprise the majority of the modern foodservice industry [17]. This study will examine whether leader integrity, as perceived by subordinates, enables the establishment of a strong interactive exchange relationship between a leader and those subordinates. The study will also investigate the importance of a leader's integrity in promoting employees' work engagement and organizational citizenship behaviors, with the aim of moderating empirical evidence of generational differences.

Leader Integrity in the Foodservice Industry
As mentioned, there is very limited research on leader integrity in the foodservice industry. According to Gatling et al. [12], the effect of leader transparency on followers cannot be underestimated in the hospitality industry, as it has considerable strategic effects, not only at the micro level, such as on followers' behaviors, but also at the macro level, such as on revenue and performance. Lack of leader integrity induces distrust among followers, making them hard to control at the organizational level. In a study of restaurant employees, Gatling et al. [6] reported that the higher a leader's behavioral integrity was, the higher the employees' confidence became; female employees, in particular, were more likely to trust leaders with high levels of behavioral integrity. Guchait, Neal, and Simons [18] found, in a study of food companies, that a leader's integrity toward food safety-demonstrated in the establishment and enforcement of food safety regulations-reduced food safety violations, indicating that leader integrity and its reflection in the behaviors of employees can reduce the risks of diseases related to food. Neal, Binkley, and Henroid [19] also suggested that employees in the foodservice industry need both consistency in their organizations and leaders who demonstrate ethical behaviors and integrity. Although some studies have stressed the effectiveness of leader integrity-and almost nobody denies its potential benefits-research on leader integrity in the foodservice industry is currently at an incipient stage.

Hypothesis Development
In a study on leader integrity and work engagement, Gollan and Wilkinson [20] noted that leaders who transparently communicate about their work and act ethically clearly motivate employees to be engaged in their own work. Vogelgesang and Lester [21] observed that employees who perceived their organizational leaders as having integrity were much more willing to participate in their organizations, and Prottas [22] found that engagement of employees in their work increased as employee perceptions of their leaders' integrity increased. Vogelgesang, Leroy, and Avolio [23] emphasized that employees who see committed leaders tend to imitate the behaviors of those leaders, thus showing a high level of engagement. According to Engelbrecht, Heine, and Mahembe [24], employees who are treated fairly and politely by their leaders are more likely to think about relationships with their leaders in terms of social exchange, thus experiencing greater job commitment, making additional efforts in their jobs, and exhibiting greater initiative. Similarly, Ugwu, Onyishi, Egwu, Akanu, Groupson, and Agudiegwu [25] indicated that employees who are highly aware of leader integrity do not feel cynicism at work and show higher job engagement than those who have lower awareness of leader integrity. These research results led to the development of the following hypothesis: Hypothesis 1: Leader integrity is positively related to employee work engagement.
Many studies have verified the existence of a positive relationship between employees' engagement and their organizational citizenship behavior. Babcock-Roberson and Strickland [26] suggested that the more employees participate in their work, the more they are committed to their organizations, thereby increasing their organizational citizenship behaviors (OCBs). According to Britt, Mckibben, Freene-Shortridge, Odle-Dusseau, and Herleman [27], although OCBs are not regarded as part of official job responsibilities in general and are less likely to be reflected in official performance evaluations, employees with higher engagement are more likely to engage in OCBs. Ariani [28] demonstrated that employees' engagement serves as a potentially important factor in predicting their OCBs and that employees with high engagement tend to participate in constructive and responsible behaviors in their organizations, while Wang, Hinrichs, Prieto, and Howell [29] argued that employees with high engagement in their work are more willing to engage in OCBs in an attempt to be useful for their organizations. Ginsburg, Berta, Baumbusch, Dass, Laporte, Reid, Squires, and Taylor [30] found that high engagement of employees is related to voluntary behaviors, such as collaborating with colleagues and helping their organizations. Matta, Scott, Koopman, and Conlon [31] asserted that OCBs are maximized when employees' work engagement increases, while Al Sahi, Zaabi, Ahmad, and Hossan [32] argued that work engagement is closely related to OCBs. Zhang et al. [2] determined that service employees' active participation and engagement in their jobs has positive effects on employees' citizenship behavior. According to Prottas and Nummelin [33], organization members with higher engagement in their jobs are more likely to perform OCBs than those who are not highly engaged. The following hypothesis is therefore posited: Hypothesis 2: Work engagement is positively related to OCBs.
Previous studies have emphasized the importance of leadership in employees' OCBs, but few have dealt with an association between leader integrity and OCBs. The following are some studies that support the current investigation: Ling, Chia, and Fang [34] found that leaders with integrity are more likely to draw OCBs from their followers. Dirks and Skarlicki [35] asserted that members who trust the compassion and sincerity of their leaders tend to offer more help and engage in more positive OCBs on their own initiative. Also, Zhang, Bai, Caza, and Wang [36] reported that employees who perceived that their leaders have integrity were more likely to engage in discretionary and voluntary behaviors, such as helping to solve problems related to other employees' work or maintaining harmonious relationships in the workplace. Park and Kim [37] suggested that OCBs increase when employees perceive that their leaders have integrity. Dobbs, Jackson, and Lindsay [38] noted that leaders and organizations with integrity have positive effects on the citizenship and non-work behaviors of subordinates and ultimately play an important role in improving organizational performance. These results led to the development of the following hypothesis:

Hypothesis 3: Leader integrity is positively related to OCBs
A generation can be defined as a group of individuals of a similar age who share historical and social experiences over a certain period [13]. Because members of a generational cohort enter school, enter the job market, and retire at similar ages, while experiencing memorable historical events at similar developmental stages [39], they perceive and interpret such historical events based on those developmental stages [40]. Studies of the impact of generational characteristics on jobs have focused on job-related factors, such as work-related values, attitudes, and preferences in an organizational context-impacts that are considered to be significant variables in an organization [41]. Nobel, Haytko, and Phillips [42] stated that Generation Y grew up while being encouraged to select whatever they wanted and to question the errors of authority, and Walsh and Taylor [43] reported that Generation Y tend to find challenging jobs in which they can actively participate in decision-making processes. According to Hurst and Good [44], members of Generation Y also tend to leave their organizations more easily than other generations because they prefer challenging work for self-development, thus exhibiting differences in work situations or values from older generations. Chen and Choi [45] suggested that Generation Y place the highest value on job environments, and, in the same context, Gursoy, Maier, and Chi [46] demonstrated that Generation Y regards a balance between work and life as being most important out of a range of job values. Generation Y also supports social causes and companies that are socially responsible [47] and may not expend as many resources and as much energy on their work compared to earlier generations, given the low centrality of work and the higher priorities of personal and family life for this generation [48]. Because Generation Y has different job values and psychological characteristics than the previous generation (Generation X), this study hypothesizes that Generation Y workers has higher expectations of leader integrity and is more affected by it being higher than Generation X workers: Hypothesis 4a: The relationships between leader integrity and work engagement in Generations X and Y are different.

Hypothesis 4b:
The relationships between leader integrity and organizational citizenship behavior in Generations X and Y are different. Figure 1 shows that, in this study, leader integrity acts as the independent variable, work engagement as a mediating variable, OCBs as the dependent variable, and employees' generation characteristics as a moderating variable. This study investigates the effects of leader integrity on work engagement (Hypothesis 1), the effects of employees' work engagement on OCBs (Hypothesis 2), and the effects of leader integrity on innovative behavior (Hypothesis 3). The study also examines the moderating effects of employees' generations on their perceptions of leader integrity (Hypothesis 4).

Samples and Procedures
The sample in this study comprised five family restaurants located in Seoul. A preliminary survey (with 30 copies) was conducted a month before the main survey to revise unclear and ambiguous expressions. The main survey was conducted in March 2019 with 300 employees from the top five family restaurants in Seoul based on 2018 sales. Prior to the survey, the authors interviewed HR personnel regarding its processes and content. We ensured that the data collected from the respondents would be kept confidential. Because it was impossible to obtain consent from all respondents, we used self-report convenience sampling. We started the survey after explaining the purpose of the study to the respondents and obtaining their voluntary consent to participate. Because of the sensitivity of the research topic and to protect anonymity, each questionnaire was collected in an envelope. The questionnaire was translated from English to Korean and then reverse translated from Korean to English, using Brislin's [49] method, to confirm that there were no differences in meaning. A preliminary survey (with 30 copies) was conducted a month before the survey to revise unclear and ambiguous expressions. A total of 300 questionnaires were distributed to the five family restaurants (60 each); 274 were collected, and 218 (72.6%) were used in the final analysis.

Instrument Development
The instrument used to measure leader integrity, work engagement, and OCBs involved a 7-point Likert scale responding to the following question: "How much do you agree or disagree with these statements?" (7: strongly agree to 1: strongly disagree).

Leader Integrity
Leader integrity is defined as the degree to which a leader's behavior is consistent with values such as honesty and confidence while complying with moral and ethical standards [50]. Leader integrity was measured using eight items based on work by Vogelgesang et al. [23] and Simons et al. [11]. A high score meant that the respondent perceived that the leader exhibited a high level of integrity. The leader integrity items included "my leader has high moral standards" and "my leader practices what he/she preaches."

Work Engagement
Work engagement is a psychological state related to a positive and satisfying job, such as the vitality and dedication felt by happy employees [51]. Work engagement was measured using five items based on Schaufeli and Bakker [52] and Schaufeli, Bakker, and Salanova [53]. The work engagement items included "I am highly engaged in this job" and "I am proud of the work that I do."

Organizational Citizenship Behaviors
OCBs are defined as creative and voluntary behavior when performing roles that are not officially given [54]. This study measured the respondents' OCBs based on research conducted by Williams and Anderson [55], as well as Podsakoff and Mackenzie [56]. The OCB items included employees that are "always ready to help those around him/her" and "conscientiously follows company rules and procedures."

Data Analysis
The collected data was analyzed using SPSS and AMOS. The Common Method Bias was verified by the Harman test and multicollinearity. The validity and reliability of the variables were tested by using Confirmatory factor analysis (CFA) and a reliability analysis. A correlation analysis was conducted to confirm whether the directionality of the measurement items was consistent with the hypotheses [57]. A total of four hypotheses were verified using Structural Equation Model (SEM) and a multi-group analysis.

Profiles of the Participants
The majority of the participants were male (52.1%); 46.7% of the participants were Generation X, while 53.3% were Generation Y, and the majority of participants had a university degree (72.5%).

Measurement of Reliability and Validity
We performed an Exploratory Factor Analysis (EFA) to confirm the CMB before the analysis. The results of the analysis showed that the explanatory power of the first factor did not exceed 50% of the total variance. Confirming the multicollinearity, all the dispersion coefficients were lower than 2.5. These results indicated that the CMB error in this study, which can occur when all variables are measured at the same time, was not serious. Table 1 shows the results of the validity and reliability analyses of the measurement items [58]. The standardized coefficients for all the items were 0.8 or higher. Cronbach's alpha and the Composite reliabilities were also 0.9 or higher [59,60]. The fit of the model was relatively satisfactory (χ 2 = 174.44; df = 132; χ 2 /df = 1.32; GFI = 0.92; NFI = 0.96; CFI = 0.99; RMSEA = 0.04), considering the degrees of freedom. The Average Variance Extracted (AVE) was also 0.7 or higher, and the Average Shared Variance (ASV) and Maximum Shared Variance (MSV) were smaller than the AVE (see Table 2). In addition, all the measurement items showed positive correlations consistent with the hypotheses in terms of directionality [61].

Moderating Effect
Hypothesis 4 postulated that the positive effects of leader integrity on the engagement and OCBs of employees would moderate by generation. To verify the moderating effects, we compared constrained and unconstrained models, determining significance by differences in the degrees of freedom (see Table 4). The analysis showed that the positive effects of leader integrity on engagement did not moderate by the generation of the employees, so Hypothesis 4a was rejected. However, the effects of leader integrity on OCBs were impacted by the generation of the employees, so Hypothesis 4b was supported. These results show that the effects of leader integrity on OCBs were stronger in Generation Y than in Generation X, indicating that leader integrity served as a significant factor for increasing the OCBs of Generation Y. Because Generation Y naturally poses questions to wrongful authority and supports socially responsible companies [42,47], they may also be affected by leader integrity in terms of OCBs more than Generation X.

Discussion of Results
Recent instances of companies facing crises due to unethical behavior have increased interest in the desirable behaviors of leaders and consequently in research related to such behaviors. Although leader immorality is considered to be one of the most disruptive forms of workplace behavior and can undermine a company's success, the negative effects caused by the unfair behaviors of leaders in the foodservice industry-an area that includes a variety of social interactions-have been overlooked as merely personal problems that should be tolerated by individual employees, not as behaviors to be addressed at the organizational level. This study aimed to determine whether leader integrity in the foodservice industry increases engagement and the OCBs of employees. The results show that leader integrity has positive effects on OCBs of employees and that the positive effects of leader integrity are stronger in Generation Y.

Theoretical and Practical Implications
There have been few empirical studies examining effects of leader integrity on the engagement and OCB of employees in the foodservice industry. Compared to those in other industries, employees in the foodservice industry work with closer social interactions due to the nature of their work environment, but studies dealing with them have been rare because morality and integrity are sensitive subjects. This study is one of the first empirical examinations to determine whether leader integrity has a significant positive effect on the responses and behaviors of employees, thus contributing to the literature in the foodservice industry and to the understanding of the process characteristics of leader integrity that increase the engagement and OCBs of employees. It also offers an academic, theoretical opportunity to explore the appropriateness of enhancing leader integrity-an opportunity that may contribute to future studies. This study is also significant in that it emphasizes the need to expand existing theories, which have so far focused on simple causal relationships, thereby clarifying what has been missed in the existing studies by controlling for the generation of the participants. The results of this study suggest two important practical implications for leader integrity. First, as this study found that leader integrity could predict engagement with the organization, jobs, and OCBs of employees, the foodservice industry-which desperately needs to reduce employee turnover-should select and train leaders who have high relational transparency and can serve as role models. To this end, foodservice organizations should create protocols for monitoring leader integrity and use performance assessments to measure that integrity, making efforts to enhance the ethical capabilities of leaders at the organizational level. Notably, the researchers confirmed that leader integrity enhanced employees' enthusiasm more strongly than organizational citizenship behavior. Given that employees with greater job engagement can be happier and spend more time in their organizations, leader integrity is also critical in terms of securing and retaining quality human resources. In other words, today's rapidly changing organizations must have healthy and motivated employees to attain sustainable outcomes [62]. For this reason, leader integrity should also be properly harnessed to create a resilient organization.
Second, this study identified a peculiarity of Generation Y-as the human resources for and future core of the foodservice industry-that may offer help in predicting the behaviors of different generations within organizations. Generation Y, on whom the positive effects of leader integrity were relatively high, was confirmed as placing a particularly high value on leader transparency. Generation Y are more likely to perform innovative behaviors when they trust their supervisors within social interactions because they have relatively high standards for leader integrity and are affected more positively by it. Generation Y are now part of the labor market as employees and will retain their share of it for several decades; this study offers empirical evidence that leader integrity should be used at the organizational level to reduce the high turnover rate of Generation Y employees and to encourage them to remain in their organizations. Compared to their predecessors, Generation Y-born during a time of social justice advocacy-have relatively high ethical expectations that may be a significant factor triggering their different organizational behaviors. It is therefore necessary to provide institutional strategies in which the integrity of leaders is stressed at the organizational level so that Generation Y employees can continue to be assured of the integrity of their leaders.

Limitations and Future Research
First, because the sample in this study included only family restaurant employees and a self-reported convenience sampling, it may be difficult to generalize the results. Further studies are needed that include more diverse samples, including from other industries. Also, CMB error could have occurred because this study was measured under the self-reporting method. Second, since this study is cross-sectional, it cannot be extrapolated over time; longitudinal studies are therefore needed. Third, this study restricted the dependent variables to engagement and OCBs; further studies may be needed that examine other psychological response variables affected by leader integrity. Fourth, this study used only generation as a control variable; further studies could examine cultural dimensions, national differences, or demographic characteristics, such as sex, as control variables.
Author Contributions: The authors contributed equally to this work. All the authors contributed to the conceptualization, formal analysis, investigation, methodology, writing of the original draft, and review and editing. All authors have read and agreed to the published version of the manuscript.

Conflicts of Interest:
The authors declare no conflict of interest.