Can Supervisor Support Mitigate the Impact of Colleague Exclusion on Silence Behavior?—A Moderated Mediating Model

In this study, we explored the generation and influence mechanism of employees’ silence behavior from the perspectives of different relationship with colleagues and leaders. A questionnaire survey was conducted among 226 employees to investigate the possibility of employees’ silence behavior in organizational situations. The results of regression analysis show that: 1) Colleagues’ exclusion has a significant positive effect on employees’ silence behavior; 2) Psychological security has a significant negative effect on employee silence behavior, and psychological security plays a part mediating role between colleagues exclusion and silence behavior; 3) Supervisor support has a significant negative moderating effect on the relationship between colleague exclusion and psychological security.


Introduction
As is known to all, voice behavior is a kind of organizational citizenship behavior which is beneficial to the development of enterprises. And with the rapid economic development and fierce competition, organizations put forward higher requirements for employees voicing their opinions. However, in organizations, there is a common phenomenon that employees are not willing to express themselves even though they know the truth and clearly know the problem or the correct direction of solution. Once a company loses employee voice behavior, it will reduce innovation opportunities and even leads to failure (Deniz, Open Journal of Social Sciences Noyan & Ertosun, 2013) [1]. This phenomenon has captured the scholars' attention of the field of organizational behavior. Morrison and Milliken (2000) [2] defined this collective cultural phenomenon that "most employees choose to retain their views in face of potential problems in the organization" as employee silence. On this basis, Khalid & Ahmed (2016) further deepened the definition of employee silence behavior. He pointed out the phenomenon that members of the organization know what is the truth but they are unwilling to express even though they know the problem or the correct direction of solution named employee silence. We found that early researches about employee silence behavior have reflected the organization members know about clearly the problems existing in the management process and also know how to improve, but for various reasons they chose to withhold their ideas without vocal expression of behavior (Morrison & Milliken, 2000) [2]. Although silent behavior can sometimes contribute to quick and effective decision-making, its negative effects are obvious in general (Knoll & van Dick, 2013) [3], Employee silence may decrease organizational change and innovation and reduce employee learning motivation and knowledge sharing engagement as well. At the same time, employees' silence behavior is also considered as an important threat to organizational change and development (Morrison & Milliken, 2000) [2]. Therefore, how to effectively reduce the silence behavior of organization members has become a key issue of organizational change management.
In previous studies, the process mechanism of employees' silence behavior is mainly shown in the following aspects: Firstly, leadership styles, such as abusive leadership, narcissistic leadership and authoritarian leadership are significantly positively correlated with employee silence behavior (

Theory and Hypothesis
Conservation of the resource (COR) suggests that the individual has been working hard to maintain, save and create individual resources (objects, the conditions, personal characteristics, energies); pressure will destroy individual resources and individual resources conservation follows the principle of increment spiral and decrement spiral (Hobfoll, 1989(Hobfoll, , 2001 [13] [14]. That means that when individuals have more resources, they are more willing to take risks to acquire new resources, such as voice behavior, innovation behavior, and so on (Wang, Zhao et al., 2017) [15]. When individual resources are scarce, individuals are more willing to adopt conservative strategies to maintain resource they have.
Colleague exclusion is a kind of stress source that can weaken individual resources, so that this study tried to use COR to explain the main effect of the model. What's more, Hobfoll (2001) [14] also pointed out that social support resources have a positive impact on individual resources which provides a strong theoretical support for the supervisor support as boundary mechanism of this study.

Colleague Exclusion and Employee Silence Behavior
Colleague exclusion refers to the perception that an individual is ignored, re-  [17]. Workplace ostracism can create interpersonal pressure, When the pressure of interpersonal rejection is too high, it even affects employees' self-control ability and psychological cognitive function (Williams, Forgas, 2005) [18]. Dealing with these stress will consumes individual psychological resources (Hobfoll, 1989) [13], and Conservation of the resource Therefore, according to the COR, when individuals perceive colleague exclusion, in order to avoid the resources loss, they are more likely to adopt a state of inactivity to avoid risks. Therefore, based on the above inference, we made the following hypothesis: H1: Colleague exclusion can positively predict employee silence behavior

The Mediating Effect of Psychological Security between Colleague Exclusion and Silence Behavior
From the definition, psychological security can be divided into individual level and team level, On the individual level, Kahn (1990) [20] defined psychological security as a kind of individual character, it reflects the employees' internal psychological state and self-awareness, staff show themselves without worrying about the negative effects of self-image, position, or occupation, when individuals have stronger feeling of that, they more likely to show themselves in the work. Ednnondson (1999) [21] expounded psychological security from the perspective of team, defined psychological security as the common belief that employees generally accept that is safe to take interpersonal risk, and is free from punishment, rejection and resistance when they have public discussion. From the definition, no matter the sense of psychological security at the team level or individual level, they all are the experiences of the internal psychological states, it reflects that individual feels others whether will be difficult or trust and respect themselves ( [23], and it is a reflection of the individual's internal resource state. According to the theory of resource conservation, stress will reduce individual resources, change resource state. And from previous researches we found that colleague exclusion can produce stress through affect relationship with co-workers (Yang, 2018) [16]. Therefore, we hypothesized that high colleague exclusion will reduce Individual resources and change internal resource state, which let employees' psychological security be low. H2a: Colleague exclusion negatively affects employees' psychological security The theory of resource conservation also told us that, when individual resources are sufficient, individuals are more willing to take risks to acquire more resources, while when individual resources are less, individuals prefer to take evasive actions to prevent risks and protect existing resources (Hobfoll, 1989) [12]. Individuals with high psychological security means that the richer the in-

Supervisory Support as a Moderator in the Influence of Colleague Exclusion on Psychological Security
Organization is a complex network of relationships that includes relationships with colleagues, superiors, and subordinates. In previous studies, supervisor ex- Based on the above analysis, this study makes the following assumptions.
Hypothesis 3: The supervisor support negatively moderates the relationship between colleague exclusion and psychological security of employees. Specifically, the higher the leader's support, the weaker the effect of colleague exclusion on the psychological security of employees, and on the contrary, the stronger the negative effect will be.

Participants and Procedures
In this study, we used a convenient sampling method to collect the questionnaires, and the sample was employees from enterprises in major cities in China.
Before the formal research, researchers explain the purpose of the study subjects and processes. We promise that the anonymity and confidentiality and ensure that the results of data will be used only for scientific research and will not cause any harmful effects for the enterprise. As soon as participators fill out the questionnaires, they submit the questionnaires directly to the researchers.

Measures
In order to ensure the reliability of data in this study, researchers mainly adopted mature scales used in previous studies. Likert 5-point scoring method was adopted in the responses of the scales involved in this study, and the grades from "totally inconsistent" to "totally consistent" were 1 to 5 respectively.
(1_strongly disagree to 5_strongly agree). The higher the score, the higher degree of compliance.

Colleague exclusion. We measured with 7-item scale developed by Hitlan &
Noel (2009) [29]. Typical questions include "Co-workers giving you the silent treatment". "Co-workers making you feel like you were not a part of the organization". Its internal consistency coefficient in our study is 0.889.  [7].
Sample items include "Don't talking to your boss even if you find potential problems in the company". The internal consistency level of this scale is found in our study is 0.818.

Analyses and Results
In order to test the hypothesis of the study, Mplus 7.11 was used to establish

Confirmatory Factor Analysis Model
Harman's one-factor test shows that, the first factor without rotation explained only 20.47% of the total variation, and did not account for most of the variation of the variable in this study. Further analysis of the competition model (Table 1) shows that the four-factor model has a good fitting degree (χ 2 = 306.098, df = 198, χ 2 /df = 1.499, CFI = 0.957, TLI = 0.950, SRMR = 0.076, RMSEA = 0.049), All the fitting indexes are superior to other alternative models (three-factor model, two-factor model and single-factor model), which indicates that the core variables in this study have good discrimination validity, and the problem of homologous variance is effectively controlled to some extent.

Statistical Analysis
SPSS.22 was used for descriptive statistical analysis of the data. Table 2 shows the mean value, standard deviation and correlation coefficient of the study variables. As can be seen from Table 2, the colleague exclusion is significantly negatively correlated with the employee psychological safety (r = −0.430, p < 0.01) and silence behavior (r = 0.340, p < 0.01). Psychological safety is negatively correlated with silence behavior (r = −0.348, p < 0.01). In addition, perceived supervisor support was significantly negatively correlated with silence behavior (r = −0.429, p < 0.01). These results provide a good foundation for the following hypothesis testing.

Result of Structural Equation Model
To test the hypothesis by using Mplus 7.11 to construct a structural equation model. In order to improve the explanatory power of model and reduce the co-linearity of the model, the researchers treated the supervisor support with grand mean centered. And control the influence of employee age, working years and other control variables. In Figure 1, path a presents the impact of colleague exclusion on psychological safety, path b shows the impact of psychological safety on silence behavior, and path c shows the direct effect of colleague exclusion on silence behavior. Path i represents perceived supervisor support's moderating effect on path b. In addition, a × b denotes the mediation effect, and a × b + c denotes the total effect of colleague exclusion on silence behavior. As can be seen from Table 3, the colleague exclusion has a significant positive effect on the silence behavior (γ = 0.199, p < 0.01). Hypothesis 1 is verified. The colleague exclusion has a significant negative effect on psychological safety (γ = −0.356, p < 0.01) and psychological safety has a significant negative effect on silence behavior (γ = −0.234, p < 0.001). Moreover, the direct effect of the colleague exclusion on silence behavior (γ = 0.286, p < 0.001) is significant. Thus, psychological safety plays a partial intermediary role between colleague exclusion and silence behavior. Hypothesis 2a, hypothesis 2b, and hypothesis 2c are supported.
Since this study examines the mediating effects models by Mplus, BOOTSTRAP     analysis is also needed. If the 95% confidence interval does not include 0, then the mediating effect is significant (Preacher et al., 2010) [31]. As can be seen from Table 4, the mediating effect of psychological safety in the relationship between colleague exclusion and silence behavior was significant, the effect value was 0.117 (p < 0.01), and the 95% confidence interval was (0.038, 0.143), excluding 0. Therefore, H2c is to be further supported.

Summary and Future Research Prospects
This study from the perspective of organizational environment discusses the possibility of employee silence behavior in the workplace when employees gain  the supervisor's support without colleagues' kind. Combining with the viewpoint of resource conservation theory, this paper examines the mediating effect of psychological security in the process that colleague exclusion affects individual silent behavior, and, as well as the interaction of supervisor support and colleague exclusion. In summary, after the testing hypotheses, this study found that colleagues' exclusion has a significant positive effect on employee silent behavior. This result is consistent with the relevant literature. What's more, we proved that psychological security has a significant negative effect on employee silence behavior, and psychological security mediates the relationship between colleague exclusion and employee silence behavior. On the other hand, perceived supervisor support negatively moderates the relation between colleague exclusion and psychological security. That is to say, when the perceived supervisor support is high, the negative relationship between the colleague's exclusion and the employee silence is weakened, and in contrast, the negative relationship is much stronger. From previous studies, it has been found that there have been a large number of studies on employee negative behavior from the perspective of workplace ostracism, and there also has been a mature accumulation of research on employee silence. However, a very common situation has been ignored in the research on the relationship between workplace ostracism and employee silence. That is, the exclusion that individuals face in the organizational context comes from different objects, which may reject or support. For example, employees may be ostracized by their colleagues but supported by their leaders in organizational situations, or ostracized by their leaders and supported by their colleagues. When studying workplace ostracism, previous literatures did not distinguish the different situations, but comprehensively discussed all the possible exclusion.
Therefore, in this study, the influence of different rejection attitudes from leaders and colleagues on employees' silence behaviors was studied in a more detailed manner, which made up for the shortcomings of previous studies.
Despite the strengths, there are still some limitations in this study. The exclusion in organizational context is from two aspects, organizational support also comes from two aspects, and they can compose four different cases, but this study only explores part of them. The situation is that how to change individual silence behavior when they expose to colleague exclusion with different levels of perceived supervisor support. We still lack studies on the case of supervisor exclusion interacting with different levels of colleague support to affect employee silence behavior. Therefore, on the one hand, future researchers can study the opposite of this study to explore whether supervisor exclusion interacts with different levels of colleague support and also affects employee silence behavior. On the other hand, future researchers can also explore more in-depth, comparing the two situations of leadership exclusion interacting with different levels of colleague support and colleague exclusion interacting with different levels of supervisor support in the organizational situation to examine which situation employee's silence behavior is higher.

Conflicts of Interest
The author declares no conflicts of interest regarding the publication of this paper.