Exploring the Relationship Between Leaders’ Core Self-Evaluations and Subordinates’ Perceptions of Servant Leadership

Abstract

Recent developments in servant leadership theory exposed a gap in the research literature regarding traits that are important to servant leaders. Our study partially addresses this gap by examining the trait of core self-evaluations and its relationship to servant leadership and leader effectiveness. The results of our study indicate that leader’s core self-evaluations are positively related to followers’ perceptions of servant leadership and leader effectiveness, and the relationship between leaders’ core self-evaluations and leader effectiveness is fully mediated by servant leadership. The results add support to current servant leadership theory by confirming the role that core self-evaluations play in servant leader emergence, and extend the research on core self-evaluations as it relates to leader performance.

Keywords

core self-evaluations leader traits servant leadership

In today’s service-oriented organizations, organizational performance is often a function of high-quality customer service, which in turn is a function of the talent and engagement level of employees (Raymundo, 2014). A recent Gallup (2015) study concludes, however, that only about a third of U.S. workers are engaged in their work, and this number is significantly less at the global level. In a globally competitive business environment, this does not bode well for organizations that increasingly rely on employees as the initial point of contact in a customer-centric environment. Employees report several factors that can influence their work engagement, including the need for organizational leaders to communicate more openly and consistently with them, help employees understand tasks and set goals, and emphasize employee strengths (Gallup, 2015). In other words, organizational leaders need to show employees they care. Showing employees they care implies that organizational leaders must adopt a leadership approach that places the support and treatment of employees at the center of its philosophy.

Over four decades ago, Greenleaf (1977) introduced just such an approach—servant leadership. While other leadership approaches have some focus on people, servant leadership is unique in that it places primary emphasis on the relationship between leader and follower. The core premise of servant leadership is that leaders give priority to the well-being of followers over the servant leader’s self-interest in an effort to increase individual and organizational performance. As Sendjaya and Sarros (2002) noted, the concept of “servant as leader” appears, at first glance, to be an oxymoron, yet the primary motivation of a servant leader is to serve followers (van Dierendonck, 2011) in ways that will help followers become effective contributors to the organization.

Although increasing research attention has been directed toward the concept of servant leadership in recent years, a number of gaps within servant leadership theory remain unaddressed. Among these is the observation that very little is known about the antecedents or leader traits associated with servant leadership (Liden, Panaccio, Meuser, Hu, & Wayne, 2014; van Dierendonck, 2011; Washington, Sutton, & Feild, 2006). It is important to close this gap because some traits influence an individual’s motivation to lead and serve and affect the quality of the relationship between leader and follower (van Dierendonck, 2011). A lack of understanding about traits of a servant leader also limits organizational leaders’ ability to select individuals with a propensity to engage in servant leader behaviors. Therefore, the purpose of this study was to partially address this gap by conducting an empirical investigation about the relationship between leaders’ core self-evaluations and followers’ perceptions of servant leadership and leader effectiveness. This study contributes to the servant leadership literature and the development of servant leadership theory by providing evidence that a leader’s core self-evaluations play an important role in shaping effective servant leadership.

Servant Leadership

At the core of servant leadership theory is the need to serve the follower in such a way as to focus on the follower’s well-being. Leaders demonstrate servant leadership by exhibiting a number of servant-oriented behaviors across several dimensions. These dimensions include (a) being a servant (e.g., giving priority to others’ interests rather than one’s own, giving credit to others); (b) empowering others (e.g., helping others grow and succeed, holding followers accountable for performance they can control); (c) making a difference (e.g., helping the organization make a contribution to the community and society, making a difference in others’ lives, altruism); (d) behaving morally/ethically; (e) exhibiting positive personal qualities, such as humility, integrity, egalitarianism, authenticity, and courage; (f) building relationships through listening, demonstrating empathy, and collaborating; and (g) demonstrating conceptual skills (Barbuto & Wheeler, 2006; Dennis & Bocarnea, 2005; Liden, Wayne, Zhao, & Henderson, 2008; Reed, Vidaver-Cohen, & Colwell, 2011; Russell & Stone, 2002; Sendjaya, Sarros, & Santora, 2008; Spears, 1995; van Dierendonck & Nuijten, 2011).

The application of these behaviors results in a number of positive organizational benefits. For example, Liden, Wayne, Liao, and Meuser (2014) reported that servant leadership behaviors exert their effect by creating a serving culture (where all members of the work unit engage in servant leadership behaviors), which is in turn related to individual job performance, organizational performance, and lower turnover. Owens and Hekman (2012) found that servant leaders can exert their effect by way of their humility—in essence, modeling to followers how to grow and view their uncertainty about their own development as legitimate.

Other studies have identified the relationship between servant leadership and valued individual and organizational outcomes, including followers’ helping and creative behaviors, organizational citizenship behaviors, organizational learning, followers’ self-efficacy, engagement with work, job satisfaction, service climate, trust in the leader and organization, and organizational commitment (Barbuto & Wheeler, 2006; Choudhary, Akhtar, & Zaheer, 2013; Hunter et al., 2013; Joseph & Winston, 2005; Liden et al., 2008; Neubert, Kacmar, Carlson, Chonk, & Roberts, 2008; Parris & Peachey, 2013; van Dierendonck & Nuijten, 2011; Walumbwa, Hartnell, & Oke, 2010). Many, if not all, of these outcomes are important to employee well-being and organizational performance, both of which are key desired outcomes of servant leadership.

Core Self-Evaluations and Leadership

Core self-evaluations represent a latent, higher order construct that contains four well-known personality traits: self-esteem, generalized self-efficacy, (low) neuroticism, and (internal) locus of control. Core self-evaluations refer to a basic evaluation of one’s worthiness, effectiveness, and capability as a person (Judge, Erez, Bono, & Thoresen, 2003). Judge and colleagues noted that the construct of core self-evaluations is a better predictor of outcomes than any of the four traits it subsumes (Erez & Judge, 2001; Judge, 2009; Judge, Erez, & Bono, 1998; Judge et al., 2003). Core self-evaluations are linked to many important work outcomes, such as job satisfaction (Judge, Heller, & Klinger, 2008), job performance (Kacmar, Collins, Harris, & Judge, 2009), organizational commitment (Stumpp, Hülsheger, Muck, & Maier, 2009), and organizational citizenship behaviors (Avey, Luthans, & Youssef, 2010), to name a few.

While much of the research on core self-evaluations has focused on individual job satisfaction, motivation, and performance, it is likely that core self-evaluations affect other aspects of an individual’s work, specifically leadership behaviors. Judge and Kammeyer-Mueller (2011) hint to this possibility when they said, “It is also possible that individuals with higher levels of core self-evaluations will undertake different leadership behaviors than those with lower levels of core self-evaluations” (p. 336). We also know that core self-evaluations are linked to individuals’ motivation to lead (Kessler, Radosevich, Cho, & Kim, 2008) and are viewed as a “bright-side” leadership trait that should have positive consequences for organizations and followers (Judge, Piccolo, & Kosalka, 2009).

Despite the potential relationship, there is limited research that has examined the relationship between leaders’ core self-evaluations and leadership, though several exceptions do exist. For example, a field study in China found that leaders’ core self-evaluations were positively related to followers’ organizational citizenship behaviors, and this relationship was mediated by leaders’ ethical behaviors (Wang, Sun, & Zhang, 2012). Another study found core self-evaluations are positively related to leaders’ service quality orientation (Salvaggio et al., 2007). A number of studies demonstrate a relationship between core self-evaluations and transformational leadership (Hu, Wang, Liden, & Sun, 2012; Resick, Whitman, Weingarden, & Hiller, 2009) and the quality of leader–member exchanges (Sears & Hackett, 2011). In sum, although limited, the emerging research suggests core self-evaluationss are positively related to leadership. We now turn our attention to why we believe core self-evaluations are related to servant leadership.

Theory and Hypotheses

Despite the increased interest in core self-evaluations and leadership, very little is known about leader core self-evaluations and whether they are associated with servant leadership (Washington et al., 2006). In fact, only a few studies have investigated any leader characteristics associated with servant leadership. These include a study that found followers’ ratings of servant leadership are positively related to their leaders’ values of empathy, integrity, competence, and the leaders’ agreeableness (Washington et al., 2006), and a study that found the leader trait of narcissism was negatively related to servant leadership behaviors (Peterson, Galvin, & Lange, 2012). One other study found a positive relationship between leaders’ agreeableness and followers’ ratings of servant leadership, and a negative relationship between leaders’ extraversion and followers’ ratings of servant leadership (Hunter et al., 2013). Despite the initial interest in leader characteristics associated with servant leadership, we are unaware of any studies that have examined the relationship between core self-evaluations and servant leadership.

Nevertheless, there are a number of theoretical and empirical reasons why we believe core self-evaluations are likely to be an important antecedent to servant leadership. From a theoretical perspective, we turn to a comprehensive theory of servant leadership proposed by Liden, Panaccio, et al. (2014). Their theory proposes (a) possible antecedents of servant leadership (including core self-evaluations), (b) servant leader behaviors (including putting followers first, helping followers grow, behaving ethically, creating value for the community, emotional healing, and empowering others), (c) intermediate processes, and (d) outcomes (e.g., organizational citizenship behavior, job performance).

In their discussion of possible antecedents to servant leadership, Liden, Panaccio, et al. (2014) suggest four reasons why core self-evaluations should be positively related to servant leadership. First, because people with positive self-concepts are less preoccupied with themselves, they are more likely to adopt altruistic behaviors and less likely to seek approval or self-gratification when given opportunities to fill leadership roles. This positive self-concept should also buffer leaders from risks of failure associated with follower development and empowerment. Second, because leaders with high self-efficacy believe in their own abilities, they should be more likely to go beyond traditional leadership and engage in the more challenging behaviors associated with servant leadership (e.g., helping followers grow, creating value for the community). Third, engaging in servant leader behaviors such as influencing followers and the community requires a belief in one’s ability to exert environmental influence. Having an internal locus of control consistent with high core self-evaluations should predispose individuals to engage in these behaviors. Finally, low neuroticism is linked to focusing on the positive side of things, and positive-focused leaders should therefore be more likely to see and further develop followers’ strengths. Taken together, this reasoning suggests a direct and positive relationship between core self-evaluations and servant leadership behavior.

From an empirical perspective, although no study has yet directly examined the relationship between leaders’ core self-evaluations and servant leadership, studies have examined the relationship between one of the four components of core self-evaluations and key servant leader behaviors. For example, helping behavior is positively related to self-efficacy (Chen, Zhu, & Zhou, 2015), a component of core self-evaluations, while being negatively related to neuroticism (or negative affectivity; Kaplan, Bradley, Luchman, & Haynes, 2009). Research has also established a positive relationship between helping behaviors and the other components of core self-evaluations, namely, self-esteem (Tang & Ibrahim, 1998) and internal locus of control (Midlarsky, Jones, & Corley, 2005). Ethical behavior, another key element of servant leadership, is negatively related to neuroticism (Xu, Yu, & Shi, 2011) and positively related to self-efficacy (Baden, 2014) and internal locus of control (Cherry & Fraedrich, 2000). Contributing to the community is positively related to self-esteem (Han & Hong, 2013) and internal locus of control (Mellor et al., 2008), and negatively related to neuroticism (Jang, 2012). The research linking key components of core self-evaluations to critical behaviors associated with servant leadership suggests that a positive relationship exists between core self-evaluations and servant leadership.

We propose three additional mechanisms by which positive core self-evaluations can lead to servant leadership. First, Washington et al. (2006, p. 704) noted that Greenleaf, widely regarded as the seminal figure behind current interest in servant leadership, believed that a leader cannot practice servant leadership unless followers have confidence in the leader’s competence. Leaders with high levels of generalized self-efficacy (an important component of core self-evaluations) see themselves as competent across a variety of tasks and domains, usually because they have repeatedly experienced success and mastery. Therefore, they are more likely than other leaders to engender confidence in their competence. Consistent with this view, Judge and Kammeyer-Mueller (2011) stated,

People who have positive core self-evaluations see themselves positively across a variety of situations, and approach the world in a confident, self-assured manner. They believe that they are capable of solving problems (high self-efficacy), worthy of respect and regard (high self-esteem), in control of and responsible for what happens to them (internal locus of control), and prone to be optimistic and free from doubts and worries. (p. 332)

Judge and Kammeyer-Mueller (2011) go further by arguing that the self-confidence of leaders with positive core self-evaluations will likely be transferred to followers, who will in turn feel more confident themselves.

Second, servant leadership requires the motivation and ability to give priority to others’ concerns (rather than one’s own) and to seek and value followers’ opinions. In this context, Judge and Kammeyer-Mueller (2011) have argued that people with positive core self-evaluations are likely to view feedback from others as nonthreatening and to use such feedback effectively. They summarized research illustrating that people with positive core self-evaluations learn more when others gave them information that differs from their own views. In contrast, people with negative (or less positive) core self-evaluations prefer to hear opinions that are consistent with their own views.

Third, servant leaders seek to make a difference in others’ lives (which includes helping the organization make a contribution to the community and society). In this context, Judge and Kammeyer-Mueller (2011) have argued that people with positive core self-evaluations likely find their work more satisfying because they pursue goals that they truly value and find personally meaningful (rather than pursuing goals for extrinsic reasons). Taken together, we believe the theoretical reasoning and empirical evidence presented, along with our own proposed mechanisms describing how core self-evaluations might lead to servant leader behavior, provide a compelling rationale to expect that leaders’ core self-evaluations will be positively related to followers’ judgments of servant leadership. Hence, we hypothesize,

Hypothesis 1: Leaders’ core self-evaluations are positively related to followers’ perceptions of servant leadership.

We also believe that leaders’ core self-evaluations are related to perceptions of leader performance. A number of studies have identified positive relationships between core self-evaluations, or one or more of its components, and employee job performance (e.g., Erez & Judge, 2001; Judge & Bono, 2001; Kacmar et al., 2009). Despite these studies, almost no attention has been directed to examining the relationship between leaders’ core self-evaluations and leader job performance or effectiveness. We expected that core self-evaluations would be positively related to leadership effectiveness.

Hypothesis 2: Leaders’ core self-evaluations are positively related to followers’ perceptions of leader effectiveness.

Finally, we argue that the effect of leaders’ core self-evaluations on leader effectiveness will occur, at least in part, through their effect on servant leadership. This belief is consistent with a long-standing view that (a) leader traits affect leadership emergence (Judge, Bono, Ilies, & Gerhardt, 2002; Lord, de Vader, & Alliger, 1986) as well as leadership styles and behaviors (Hoffman, Woehr, Maldagen-Youngjohn, & Lyons, 2011) and (b) leadership styles and their associated behaviors (rather than leader traits) are the immediate precursors of leader effectiveness, including individual-, group-, and organization-level outcomes (e.g., Searle & Barbuto, 2013). This view implicitly underlies the extensive research that has examined and linked the relationship between leadership styles, such as charismatic leadership, transformational leadership, and leader–member exchange, to various measures of leader effectiveness and outcomes (Fuller, Patterson, Hester, & Stringer, 1996; Gerstner & Day, 1997; Lowe, Kroeck, & Sivasubramaniam, 1996; Piccolo et al., 2012). Hence, we hypothesize,

Hypothesis 3: Servant leadership mediates the relationship between leaders’ core self-evaluations and followers’ perceptions of leader effectiveness (see Figure 1).

Figure 1.

Hypothesized model.

Figure 1 illustrates the hypothesized model.

Method

Research Setting and Procedures

Data were collected from a facilities maintenance organization of a large university in the southeastern United States. To facilitate the data collection, online surveys were created and administered to two separate groups: (a) organizational leaders (i.e., managers) and (b) the leaders’ subordinates. For the purposes of this study, a leader was defined as any individual with the formal authority to perform performance evaluations for subordinates. The resulting sample consisted of assistant supervisors, supervisors, assistant managers, managers, assistant directors, and directors. To collect the data, employees were provided a link to a web page containing web links for both the leader and subordinate surveys. Employees then clicked on the link for the relevant survey. All employees were allowed to complete the surveys on work time and at computers within their work area.

Sample

Survey invitations were sent to leaders (n = 72) and their subordinates (n = 469) inviting them to assist with a study of managerial performance. After accounting for cases of incomplete or blank responses and creating matched sets between a single leader and all of the subordinates that responded for that leader, we retained a total of 64 complete matches: n (manager) = 64, n (subordinate) = 283, total N = 347. Of the complete matched sets, 57 sets (89%) had three or more complete subordinate ratings for each manager. The remaining seven cases included managers with fewer subordinates. In these cases, 30% or more of the managers’ subordinates responded (three cases had 100% response rate; two cases had 50% response rate; two cases had 30% response rate), so these cases were retained. The overall response rate for managers was 89%, and the response rate for subordinates was 60%.

Most leader respondents were male (87.5%), and most were 41 years old or older (82.8%). Many leaders had a 4-year (bachelor’s) degree or higher (50.8%), were with their organization for 11 or more years (59.4%), and were in their position 3 or more years (60.9%). Subordinate characteristics were somewhat similar. Most were male (76.0%), older than 40 years (66.8%), and in their respective position 3 or more years (67.5%) and had organizational tenure of 3 or more years (76.7%). Education levels among subordinates tended to be clustered around 2-year (associate’s) degrees, technical certificates, and high school diplomas (68.9%), with many (38.2%) possessing only a high school diploma.

Measures

Core Self-Evaluations

Leaders completed the Core Self-Evaluations Scale (Judge et al., 2003), a 12-item scale that displays a unitary factor structure as well as acceptable internal consistency, test–retest reliability, and intersource agreement (i.e., self with important others). Sample items include “I am confident I get the success I deserve in life” and “When I try, I generally succeed.” Each item was rated on a 6-point scale (1 = strongly disagree to 6 = strongly agree). Coefficient alpha in the current study was .72.

Servant Leadership

We assessed followers’ perceptions of servant leadership using a 14-item measure by Ehrhart (2004) that asks followers to rate the extent to which the leader demonstrated behaviors associated with servant leadership. We chose this measure because it was designed to capture followers’ perceptions of servant leadership, is psychometrically sound, and is of an appropriate length for the needs of the study. Ehrhart developed the items after a review of the servant leadership literature. Item development emphasized putting followers’ concerns first, and ethical behavior. Ehrhart demonstrated the construct validity of this measure by testing via confirmatory factor analysis that it was related to, yet distinct from, well-established measures of transformational leadership and leader–member exchange and explained significant incremental variance in predicting satisfaction with the manager, procedural justice, trust in the leader, and organizational commitment. Sample items include “My supervisor is sensitive to department employee’s responsibilities outside the workplace” and “My supervisor works hard at finding ways to help others be the best they can be.” Each item was rated on a 5-point scale (1 = to a very small extent to 5 = to a very great extent). Coefficient alpha in the current study was .96.

Leader Effectiveness

In choosing a measure of leader effectiveness, we considered three criteria: (a) the measure must align with the task and contextual elements of a leader’s behaviors, (b) the measure must have an acceptable level of reliability, and (c) given typical organizational constraints (i.e., time and money), the number of items must not be overly burdensome to the respondents. We selected an eight-item measure by Mount (1984) that met these criteria and was reflective of basic work behaviors observable by subordinates. This measure was based on items taken from the Management Position Description Questionnaire (Tornow & Pinto, 1976), and the statements were worded based on the responding referent group. Mount tested the measure in a study with manager self-ratings, as well as ratings from their supervisors and subordinates; he found a scale reliability of .87. Sample items include “Serves as a resource that others can rely on for technical advice” and “Encourages employees to reach high standards of quality and quantity.” Each item was rated on a 5-point scale (1 = consistently performs way below expectations to 5 = consistently performs way above expectations). Coefficient alpha in the current study was .94.

Control Variables

In the analyses that follow, we controlled for the effect of leaders’ psychological capital and cognitive ability on servant leadership. The construct of psychological capital has its origin in the positive organizational behavior movement. According to Luthans, Avolio, Avey, and Norman (2007), psychological capital is composed of four facets: (a) self-efficacy, having the confidence to take on challenging tasks and put in the effort to succeed; (b) optimism, believing one can succeed now and in the future; (c) hope, having the will to succeed and the ability to identify, clarify, and pursue the way to success; and (d) resiliency, the ability to bounce back from adversity to attain success.

Resick et al. (2009) have argued that core self-evaluations represent the pinnacle of positive, or “bright-side,” personality constructs and should therefore be related to both leadership and organizational performance. Indeed, the theoretical model proposed by Liden, Panaccio, et al. (2014) specifically includes core self-evaluations and not other “bright-side” constructs, such as hope, optimism, and resiliency. It is important therefore to control for these other constructs to demonstrate that it is indeed core self-evaluations, above and beyond other “bright-side” constructs, that are related to servant leadership. Otherwise, a relationship between core self-evaluations and servant leadership could be merely an artifact of a relationship between any “bright-side” characteristic and leadership.

To assess Psychological Capital, we included the 24-item Psychological Capital Questionnaire (Luthans et al., 2007). This scale measures the level of a manager’s state-based self-efficacy, optimism, hope, and resiliency. Each item was rated on a 6-point scale (1 = strongly disagree to 6 = strongly agree). Coefficient alpha in the current study was .89.

We also included a measure of leaders’ cognitive ability as a control variable because cognitive ability has repeatedly been found to be a strong predictor of job performance, including managerial performance (Bertua, Anderson, & Salgado, 2005). Furthermore, according to van Dierendonck (2011), cognitive complexity (a related construct) may be influential in a person’s development toward servant leadership because it reveals a person’s ability to perceive differentiated social behavior and allows for a more accurate judgment of social situations. In addition, servant leadership requires leaders to occasionally step back and allow others to learn from their own experiences, be able to forecast needs beyond the immediate present, predict outcomes of situations, reason through conflicting situations, and help overcome differences. Consequently, one might expect cognitive ability to be positively related to servant leadership.

To assess cognitive ability, we used a short version of the Raven’s Advanced Progressive Matrices (APM; Bors & Stokes, 1998). The full Raven’s APM is a widely used measure of g or fluid intelligence (Bors & Stokes, 1998; Carpenter, Just, & Shell, 1990) said by some to be the purest measure of fluid intelligence (Day, Arthur, & Gettman, 2001). Furthermore, because it is a nonverbal test of intelligence, it is generally considered culture-neutral (Arthur & Day, 1994) and not susceptible to differences in reading ability (McKay, Doverspike, Bowen-Hilton, & Martin, 2002). The test was designed to measure the ability of respondents to solve problems and handle complexity through progressively more complex puzzles (Carpenter et al., 1990; Raven, 2000). The short version of the test consisted of two practice puzzles and 12 scored puzzles. Bors and Stokes obtained a correlation of .92 with the full-length APM and an internal consistency (alpha) of .73. In the current study, internal consistency reliability was .82.

Procedures

The multilevel nature of this study lends itself to analysis using random coefficient modeling, that is, hierarchical linear modeling (Raudenbush & Bryk, 2002). Hierarchical linear models are the appropriate statistical mechanism for investigating and drawing conclusions about data that cross between levels of analysis (Hofmann, Griffin, & Gavin, 2000), as is the case in this study.

Results

Table 1 reports the means, standard deviations, and intercorrelations among the study variables within each level. Two of the correlations presented are sufficiently high to merit additional comment. At the leader level (Level 2), the correlations between psychological capital and core self-evaluations are positive and statistically significant. Significant correlation coefficients among independent variables are often assumed to suggest the possibility of multicollinearity; however, according to Kline (2005), multicollinearity is not an issue unless the coefficients exceed 0.85. Additionally, a calculation of the coefficient of determination (r² = .38) indicates only moderate shared variance between the variables, suggesting that these variables are capturing information about distinct constructs. Additionally, previous research has established that the construct of Psychological Capital is distinct from core self-evaluations (Luthans et al., 2007), so we deemed this evidence sufficient to consider the constructs distinct.

Table 1.

Means, Standard Deviations, and Intercorrelations.

Variable	M	SD	1	2	3	4	5
Level 1
1. Perceptions of servant leadership	3.52	0.91	(.96)
2. Perceptions of leader effectiveness	3.7	0.92	.77**	(.94)
Level 2
3. Core self-evaluations	4.68	0.53			(.72)
4. Cognitive ability	5.92	3.28			.22	(.82)
5. Psychological capital	4.94	0.49			.62**	.38**	(.89)

Note. Level 1 n = 283; Level 2 n = 64; Cronbach’s alphas are on the diagonal.

p < .01.

Likewise, the correlation between perceptions of servant leadership and perceptions of leader effectiveness at Level 1 is positive and statistically significant, and high enough to indicate a possible lack of discriminant validity between constructs. Given that the coefficient of determination was higher (r² = .59) than that of Psychological Capital–core self-evaluations, and no previous research had established construct distinctiveness between the two measures, we felt additional examination was necessary. Consequently, we ran a confirmatory factor analysis on these two variables. The results indicated that a two-factor model achieved a satisfactory model fit (see Table 2 for goodness-of-fit indicators). Based on these results, we treated servant leadership and leadership effectiveness as two separate constructs in our analyses.

Table 2.

Goodness-of-Fit Indicators of Models for Servant Leadership and Leader Effectiveness.

Model	χ²	df	χ²/df	CFI	RMSEA	RMSEA CI₉₀	SRMR
Single-factor model	1420.72**	299	4.75	.81	.12	[.12, .13]	.06
Two-factor model	990.90**	298	3.33	.88	.10	[.09, .10]	.05

Note. df = degrees of freedom; CFI = comparative fit index; RMSEA = root mean square of error approximation; CI = confidence interval; SRMR = standardized root mean square residual.

p < .01.

To test our hypotheses, we analyzed intercepts-as-outcome models using HLM 7 for Windows (Raudenbush, Bryk, & Congdon, 2011). Before testing Hypothesis 1, it was important to determine the amount of variance in the outcome variable due to the Level 2 variable (Davison, Kwak, Seo, & Choi, 2002), accomplished by performing an analysis of the null model (entering the outcome variable into a model by itself). The total amount of variance accounted for by Level 2 variables can be determined by dividing the intercept variance component by the sum of the intercept variance component and the Level 1 variance component. The result is the intraclass correlation coefficient (ICC) and indicates the amount of variance in the outcome variable accounted for by the Level 2 variable(s). For Hypothesis 1, we inserted servant leadership into the model as the outcome variable and calculated the null model, which resulted in ICC = .277, indicating that approximately 28% of subordinate perceptions of servant leadership are due to leader differences. This value is within accepted ranges to proceed with hypothesis testing (Aguinis, Gottfredson, & Culpepper, 2013). To test the hypothesis, we added core self-evaluations as a predictor variable at Level 2. We also included psychological capital and cognitive ability at Level 2 as control variables. As seen in Table 3, the results indicate that leaders’ core self-evaluations were positively related to followers’ perceptions of servant leadership after controlling for the leaders’ cognitive ability and psychological capital. This finding supports Hypothesis 1.

Table 3.

Hypotheses Testing.

	Hypothesis 1 (servant leadership as outcome)		Hypotheses 2 and 3 (leader effectiveness as outcome)
Level and variable	Null model	Hypothesis 1	Null model	Hypothesis 2	Hypothesis 3
Level 1
Intercept (γ₀₀)	3.54** (0.077)	3.53** (0.074)	3.706** (0.073)	3.670** (0.071)	3.70** (0.037)
PSL (γ₁₀)					0.78** (0.040)
Level 2
CSE (γ₀₁)		0.45** (0.167)		0.35* (0.154)	0.00 (0.080)
CA (γ₀₂)		−0.01 (0.024)		0.00 (0.023)	0.01 (0.011)
PsyCap (γ₀₃)		−0.23 (0.197)		−0.18 (0.203)	0.00 (0.109)
Additional information
ICC	.277		.205

Note. PSL = perceptions of servant leadership; CSE = core self-evaluation; CA = cognitive ability; PsyCap = psychological capital; ICC = intraclass correlation coefficient. Values in parentheses are standard errors. Level 1 n = 283 and Level 2 n = 64.

p < .05. **p < .01.

To test Hypothesis 2, we built a new model, with subordinate ratings of leader effectiveness as the outcome variable. As with Hypothesis 1, we determined the ICC value (the amount of variance in the outcome variable accounted for by any Level 2 variables with leader effectiveness as the outcome variable) for this model to be .21, which indicated that approximately 21% of the variance in leader effectiveness ratings might be attributed to Level 2 variables. We then added core self-evaluations as the indicator variable (along with psychological capital and cognitive ability as control variables) at Level 2 and ran the analysis. As can be seen in Table 3, leaders’ core self-evaluations were positively related to followers’ perceptions of leader effectiveness after controlling for the leaders’ cognitive ability and psychological capital, supporting Hypothesis 2.

To test Hypothesis 3, we added subordinate ratings of servant leadership as a Level 1 predictor to the model created to test Hypothesis 2. As seen in Table 3, servant leadership was positively related to leader effectiveness after controlling for leaders’ core self-evaluations, and leaders’ core self-evaluations were no longer significantly related to leader effectiveness after controlling for servant leadership. These findings demonstrate that the effect of leaders’ core self-evaluations on leader effectiveness is fully mediated by servant leadership, and hence support Hypothesis 3.

Discussion

If employers desire to cultivate a servant leader culture, they need direction about which attributes are most important to the selection and development of employees that are most likely to evolve into servant leaders. Yet very little research exists about the traits that affect servant leadership. Our study partially addresses this issue by demonstrating how one attribute, core self-evaluations, is important to servant leadership. The results of this study indicate that leader core self-evaluations appear to affect servant leadership and its associated behaviors, which in turn are the immediate precursors of leader effectiveness.

Theoretical and Methodological Implications

This finding has a number of theoretical and methodological applications. From a theoretical standpoint, this finding extends the emerging literature concerning the relationship between core self-evaluations and leadership approaches in general. To date, research has found that leader’s core self-evaluations are related to transformational leadership, and the results of our study add to this literature by providing evidence that leaders’ core self-evaluations are also related to servant leadership. Additionally, this study extends theory development of servant leadership by providing a test of a theoretical model, which is in line with Colquitt and Zapata-Phelan’s (2007) discussion of theory building. Specifically, this study supports Liden’s, Panaccio’s et al. (2014) theoretical model of servant leadership by demonstrating an empirical relationship between leaders’ core self-evaluations and followers perceiving those leaders as servant leaders.

We also found that core self-evaluations were positively related to followers’ perceptions of the leader’s effectiveness, extending the research on the relationship between core self-evaluations and job performance. Most of the previous research on this relationship has focused on the job performance of nonleaders (i.e., outside of a leadership role). Moreover, our finding extends research on core self-evaluations by illustrating their importance for leadership effectiveness.

Finally, our study provides a methodological contribution to the field of servant leadership. van Dierendonck (2011) stated, “We have to cope with another methodological weakness of the field, namely, that some studies consisted of leaders estimating their own leadership behavior . . . Here, the perspective of the follower on a leader’s behavior is clearly missing” (p. 1252). Our study addresses this issue by assessing servant leadership from the follower’s perspective.

Practical Implications

From a practical standpoint, this finding is valuable to those selecting and preparing future leaders in organizations seeking to cultivate a servant leadership culture. The emphasis on customer service and the expectation that leaders will help develop employees to their fullest potential in our current service-based economy requires leaders to use a more personal approach to leadership (Liden, Wayne et al., 2014). In that context, organizations should consider screening candidates for core self-evaluations when selecting individuals for leadership positions where servant leadership is a desired leadership approach. Once leaders are selected, leader development programs may prove to be more effective by including a special emphasis on leader self-efficacy (a core component of core self-evaluations). This emphasis could be accomplished by including the opportunity for new leaders to model others who are successful and adopt a small-wins strategy where new leaders are taught to break big problems into smaller units that can be attacked individually, thereby generating a sense of progress and efficacy (Whetten & Cameron, 2007).

Strengths, Limitations, and Directions for Future Research

A strength of the current study is that we collected our measure of core self-evaluations from leaders themselves, but we collected our outcome measures from followers. Furthermore, given our managers had, on average, 11 years of tenure and their subordinates had, on average, 3 years of tenure, our field study was conducted in a very stable environment where employees and managers had ample time to become thoroughly acquainted with each other’s attributes and behavior. We also controlled for both general mental ability as well as psychological capital, both of which are strongly related to performance. Still, we collected our measures of servant leadership and leader effectiveness from followers in a single survey, thereby potentially raising concerns about common-source (method) variance. Nonetheless, it is noteworthy that only one of our hypotheses would be affected by this limitation. That is, the relationships between leaders’ core self-evaluations and (a) servant leadership and (b) leader effectiveness would not be affected by common source bias.

Another limitation is that ratings of servant leadership and leadership effectiveness were obtained from the same source (i.e., followers). We noted a high correlation between the two measures, although a confirmatory factor analysis indicated that it was appropriate to treat the two measures as separate constructs. Nonetheless, it would be helpful for future research to obtain an objective measure of leader effectiveness (e.g., department sales). In the meantime, future research should continue to extend servant leadership theory by examining other possible precursors of servant leadership. For example, van Dierendonck (2011) has proposed that the leader’s level of moral development (Kohlberg, 1976) is likely a precursor of servant leadership.

It would also be beneficial to demonstrate that similar findings are observed using other measures of servant leadership and alternative measures of leadership effectiveness. Of special interest would be organizational outcomes associated with corporate social responsibility and sustainability (van Dierendonck, 2011). Finally, from a methodological perspective, it would be ideal if the precursors of servant leadership, perceptions of leadership, and outcomes of leadership could be collected from three different sources (e.g., leaders, followers, and organizational records, respectively) thereby eliminating any possible concerns with mediation analyses where two measures are collected from the same source.

In sum, the literature on servant leadership continues to evolve. This study contributes to this literature by demonstrating that leaders’ core self-evaluations are an important determinant of followers’ perceptions of servant leadership. It also shows that servant leadership, in turn, mediates the relationship between leader’s core self-evaluations and leadership effectiveness. Undoubtedly there are additional leader traits that contribute to the effectiveness of servant leaders, and we encourage future research on what these traits might be. We view this study as a step in that direction.

Footnotes

Acknowledgements

We wish to thank Dr. Christopher L. Shook for his helpful comments on an earlier draft of this article.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Author Biographies

C. Brian Flynn is an Assistant Professor in the Department of Management at the University of North Florida. His research interests include selection, personality, and managerial/leadership development. He completed his Ph.D. at Auburn University. Prior to beginning his Ph.D., he performed human resource and management roles in the customer service, aerospace, and IT industries.

James W. Smither is a Professor in the Management and Leadership Department at La Salle University. His research interests include multi-source feedback and leadership development. He received his Ph.D. in industrial and organizational psychology from Stevens Institute of Technology.

Alan G. Walker is an Associate Professor in the Management Department at Auburn University. His research interests include spirituality in the workplace and organizational ethics. He received his Ph.D. in industrial and organizational psychology from Bowling Green State University.

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