Linking Proactive Personality to Well-Being: The Mediating Role of Person-Environment Fit

This study used work adjustment theory to develop a model of linking proactive personality to employee job satisfaction, career satisfaction, and job involvement. This model was tested using two samples. The first sample, collected using a cross-sectional survey, consisted of 278 employees nested in 25 organizations located in Taiwan, including 17 service organizations and eight manufacturing organizations. The second sample, collected using a two-wave survey, consisted of 300 employees nested in 22 organizations located in Taiwan, including eight service organizations and 14 manufacturing organizations. The results of hierarchical linear modeling (HLM) analysis of Sample 1 revealed that person-job fit and person-organization fit fully mediated the effects of proactive personality on job satisfaction and career satisfaction. The results of HLM analysis of Sample 2 revealed that person-job fit and person-organization fit fully mediated the effects of proactive personality on job satisfaction, career satisfaction, and job involvement. Results are offered, and implications are discussed.

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Original Research
Employee proactivity has become an important determinant of organizational success due to global competition, increasing uncertainty of the industry environment, the need for innovation, the increasing number of decentralized organizational structures, and the requirements for self-directed learning in today's organizations (Crant, 2000;Erdogan & Bauer, 2005;Frese & Fay, 2001;Grant & Ashford, 2008;Li et al., 2014;Major et al., 2006;Parker et al., 2006). Thus, employees with a strong proactive personality are valuable for the employing organization (Crant, 2000;Fuller & Marler, 2009;Z. Wang et al., 2017). Proactive personality was defined by Bateman and Crant (1993) as "relatively unconstrained by situational forces, and who effects environmental change" (p. 105). Dawis and Lofquist (1984) indicated that work adjustment is a process that reflects the responsiveness of an individual and his or her work setting to each other's requirements. The dimension called correspondence is the extent to which the needs of the employee and/or the work environment are met. Work adjustment theory posits that the motive behind an employee's work is to realize and retain a correspondence between his or her characteristics and the work surroundings (Dawis & Lofquist, 1984). In contrast to passive individuals' submission to their environment, proactive individuals tend to look for opportunities to improve their work setting to be congruent with their characteristics (Bateman & Crant, 1993;Crant, 2000;Tolentino et al., 2014). Therefore, it is reasonable to expect these proactive employees to have better person-job (P-J) and person-organization (P-O) fit. Although Erdogan and Bauer's (2005) data indicated that proactive personality is positively related to P-J fit and P-O fit, to our knowledge, previous literature has not explored or tested why proactive employees tend to have better P-J and P-O fits in organizational settings. To fill this important gap in the literature, the first objective of this study was to ascertain whether proactive personality is positively associated with both P-J and P-O fits.
Proactive personality literature has shown that proactive personality is positively associated with job satisfaction (e.g., Liao, 2015) and career satisfaction (e.g., Jawahar & Liu, 2017), and both P-J and P-O fits are positively associated with job satisfaction (e.g., Bauer et al., 2019) and career satisfaction (e.g., Erdogan & Bauer, 2005). According to work adjustment theory's third proposition (Dawis & Lofquist, 1984), an employee's satisfaction is determined by the degree of congruence between the requirements of the employee and those of the work environment. Based on this theory and the evidence, it is reasonable to expect that both P-J and P-O fits would mediate the relationships between proactive personality and career satisfaction and job satisfaction. Furthermore, the person-environment fit model was discovered to be useful for predicting job involvement (Blau, 1987), and P-O fit was discovered to be positively associated with job involvement (e.g., Rich et al., 2010). Accordingly, this study also proposed that both P-J and P-O fits would mediate the relationship between proactive personality and job involvement. An employee's job involvement is important for the employing organization as, for example, job involvement is positively associated with job performance (Keller, 1997). However, the relationship between proactive personality and job involvement has never been explored or tested. Examining the mediating roles of P-J fit and P-O fit in the mechanism linking proactive personality with job involvement might extend work adjustment theory's (Dawis & Lofquist, 1984) third proposition to suggest that employees' person-environment fit in the employing organization determines not only employees' satisfaction but also employees' job involvement (Lange & Pfarrer, 2017). Therefore, except for job satisfaction and career satisfaction, this study tested an extra outcome variable, job involvement, with Sample 2.
The work adjustment theory's (Dawis & Lofquist, 1984) underlying mechanism linking proactive personality with employees' job satisfaction, career satisfaction, and job involvement has not been fully investigated or examined. However, the knowledge of this work adjustment process is valuable for practitioners and academics. Theoretically, this mediating mechanism may provide evidence for using work adjustment theory (Dawis & Lofquist, 1984) to link proactive personality and employees' job satisfaction, career satisfaction, and job involvement. Using this mediating process's knowledge, administrators or career counselors could learn to preclude the indirect and negative influences of the less proactive personality on employees' job satisfaction, career satisfaction, and job involvement. To fill this gap in previous research, this study's second objective was to examine the mediating influences of P-J and P-O fits on the relationships of proactive personality with job satisfaction, career satisfaction, and job involvement.
Employees' job satisfaction, career satisfaction, and job involvement are important for organizations. For example, except for the importance of job involvement mentioned earlier, job satisfaction is negatively associated with employee turnover (Wright & Bonett, 2007), while career satisfaction is positively associated with affective organizational commitment (Carson et al., 1996).

Theory and Hypotheses
Proactive Personality and P-J and P-O Fits Dawis and Lofquist's (1984) work adjustment theory indicated that the basic motive behind employees' work is to seek a work setting congruent with their needs, abilities, and values. People are not "passive recipients of environmental presses" (Buss, 1987(Buss, , p. 1220; people "create environments and set them in motion as well as rebut them" (Bandura, 1986, p. 22). The essential characteristic of proactive behavior is that people purposefully and directly alter their social or nonsocial environments (Bateman & Crant, 1993;Buss, 1987). Like other dispositions, the tendency to change the environment varies among individuals (Bateman & Crant, 1993). Unlike passive employees who tolerate their environment, proactive employees look for opportunities and effectively change them (Bateman & Crant, 1993).
Based on the perspective of interactionists (Bandura, 1977;Schneider, 1983), Crant (1995) indicated that proactive employees intentionally influence their environment to make their job and organization more suitable. Seibert et al. (1999) posited that, unlike their passive counterparts, proactive employees would try their best to choose or create work surroundings congruent with their values and needs. Accordingly, this study expected that compared with their passive counterparts, proactive individuals would be more likely to engage in various proactive actions, such as job search, career planning, and job crafting, to search for or create environments that fit their characteristics. Cable and DeRue (2002) indicated that P-J fit includes needs-supplies fit and demands-abilities fit. Furthermore, Wang et al. (2011) indicated that "perceived needs-supplies fit occurs when employees' needs, desires, or preferences are perceived to be met by the jobs that they perform" (p. 166). They also indicated that "perceived demands-abilities fit occurs when employees' knowledge, skills, and abilities are perceived to be commensurate with what the job requires" (p.166). P-O fit is defined as "the congruence between the norms and values of organizations and the values of persons" (Chatman, 1989, p. 339). In the following paragraphs, some indirect evidence is provided to demonstrate the various means that proactive individuals may take to enhance their P-J fit or P-O fit.
The literature indicates that proactive personality is positively associated with job search intensity (Zacher, 2013) and career initiative (Seibert et al., 2001), including career planning and other career management behaviors. Applicants who conduct a more considerable job search would have more job offers and a greater probability of choosing a job and organization that fit their needs (Breaugh, 1992;Saks & Ashforth, 2002). Saks and Ashforth (2002) indicated that career planning better prepares job seekers to search for and gain a job and organization they perceive congruous with their career goals. They also found that career planning is positively related to postentry P-J fit and that both job search intensity and career planning are positively associated with pre-entry P-J and P-O fits, both of which are positively associated with postentry P-J and P-O fits.
Based on the theory of proactive personality (Crant, 2000), Bakker et al. (2012) argued that in work settings, proactive employees tend to create suitable circumstances for themselves. Their work revealed a positive correlation between proactive personality and job crafting, a selfinitiated action defined as "the physical and cognitive changes individuals make in the task or relational boundaries of their work" (Wrzesniewski & Dutton, 2001, p. 179). Employees proactively participate in job crafting to alter their jobs to fit their abilities and preferences (Bakker et al., 2012). In addition, job crafting is positively associated with P-J fit .
Proactive individuals were found to have better adjustment outcomes in task mastery (Kammeyer-Mueller & Wanberg, 2003;Parker & Sprigg, 1999), work group integration (Kammeyer-Mueller & Wanberg, 2003), and political knowledge (Kammeyer-Mueller & Wanberg, 2003) than passive ones. Kammeyer-Mueller and Wanberg (2003) defined task mastery as an employee's evaluation of his or her competence to carry out his or her job responsibilities. Work group integration refers to perceived social acceptance and support from colleagues, whereas political knowledge is defined as an individual's interpersonal and informal power connections in the organization (Kammeyer-Mueller & Wanberg, 2003). Both task mastery and work group integration (social integration) have been found to positively correlate with both P-J and P-O fits (Gruman et al., 2006).
Proactive personality was also positively related to career adaptability (e.g., Jiang, 2017;Tolentino et al., 2014). Career adaptability was defined as "the readiness to cope with the predictable tasks of preparing for and participating in the work role and with the unpredictable adjustments prompted by changes in work and working conditions" (Savickas, 1997, p. 254). When individuals need to cope with occupational transitions or problems, career adaptability enables them to make the adjustments necessary to have a good person-environment fit (Savickas & Porfeli, 2012). In addition, Jiang's (2016) study indicated that career adaptability is positively associated with P-J fit and P-O fit.
Although previous studies have not hypothesized and examined positive associations of proactive personality with P-J fit and P-O fit, Erdogan and Bauer's (2005) data showed positive correlations between proactive personality and both P-J fit and P-O fit. In addition, Wu and Chi's (2020) data also indicated that proactive personality is positively related to P-O fit. Based on this reasoning and the empirical evidence, the following hypotheses are presented.
Hypothesis 1a: Proactive personality will positively associate with P-J fit. Hypothesis 1b: Proactive personality will positively associate with P-O fit.

The Mediating Effects of P-J Fit and P-O Fit
Job satisfaction was defined as "a pleasurable or positive emotional state resulting from the appraisal of one's job or job experiences" (Locke, 1976(Locke, , p. 1304. Erdogan et al. (2004) defined career satisfaction as "individuals' satisfaction with their rates of progress toward achieving career goals based on their accumulated work experiences that span the course of their work-life" (p. 309). Furthermore, job involvement was defined as "the extent to which the individual sees his or her job as important to his or her selfimage" (Blau, 1987, p. 243). The following paragraphs address the mediating effects of P-J fit and P-O fit on the relationships between proactive personality and employee job satisfaction, career satisfaction, and job involvement. Wang et al. (2011) indicated that when individuals experience that employing organization's norms and values and their values are similar, they tend to have a satisfaction with the work surroundings because what they care for is consistent with the emphases proposed by the work environment. Compared with employees with low P-O fit, employees with high P-O fit are more likely to receive social and political support from their organization and its members. Accordingly, they tend to perceive their circumstances as comfortable and supportive and thus report greater job satisfaction (Bretz & Judge, 1994;Schreiber, 1983). Bretz and Judge (1994) showed that P-O fit is positively associated with job satisfaction.
As individuals with high P-O fit share employing organization's values, they tend to tailor their daily behavior to organizational expectations. By doing so, individuals with high P-O fit may receive better performance appraisals from their supervisors, feel a considerable sense of accomplishment, and earn more raises and promotions (Schein, 1992;Vogel & Feldman, 2009). In addition, Hall's (1971) career development model indicated that psychological success leads to higher self-esteem, which then leads to increased job involvement. Consequently, this study proposed that the psychological success of individuals with high P-O fit may lead to increased job involvement. P-O misfit may result in poor communication, misunderstandings, or conflicts between an employee and the organization. The employee may also encounter high role conflict and role ambiguity (Tsui & O'Reilly, 1989). Erdogan et al. (2004) found that P-O misfit may contribute to poor communication and collaboration with colleagues and low organizational identification. Thus, employees with high P-O fit can be more satisfied with their job and career. Edwards and Cable (2009) found that P-O fit promotes individuals' trust in their employing organization, communication among employees, and interpersonal attraction among organizational members, all of which increase job satisfaction. Cable and DeRue (2002) argued that employees with high P-O fit tend to commit themselves to the organization's mission, ascribe the organization's actions toward them to positive motives, and experience a greater attachment to the employing organization. Thus, P-O fit is expected to be positively related to career satisfaction and job satisfaction. P-J fit comprises needs-supplies fit and demands-abilities fit (Cable & DeRue, 2002). Locke (1976) posited that "the degree to which the job fulfills or allows the fulfillment of the individual's needs determines his degree of job satisfaction" (p. 1303). Thus, when individuals' needs match the supplies offered by their jobs, job satisfaction may increase. Cable and DeRue (2002) posited that individuals who invest their time, energy, and knowledge in their careers expect to have their needs met. Thus, they suggested that individuals evaluate their career satisfaction based on whether their jobs fulfill their personal needs. In addition, they found positive relationships of needs-supplies fit with career satisfaction and job satisfaction. Theoretically, both the employee's characteristics and the characteristics of the work environment determine job involvement (Holland, 1973;Presthus, 1965;Rabinowitz, 1981;Wanous, 1974). Wanous (1974) believed that if an individual prefers a job that offers challenges and autonomy, this individual would be more involved in that kind of job. Consequently, needs-supplies fit is expected to be positively associated with job involvement. Liu et al. (2015) indicated that when employees' abilities exceed the demands of their jobs, their self-esteem deteriorates because overqualified employees do not fully apply their skills and knowledge to their jobs. Consequently, they may believe that they are not significantly contributing to the organization. Likewise, underqualified employees would be less efficient and more likely to have poorer work outcomes. Their self-esteem is expected to decrease (Cable & DeRue, 2002). In contrast, demands-abilities fit employees tend to perform competently and contribute significantly to the organization. Successful work experiences can enhance the self-esteem of employees with demands-abilities fit (Korman, 1970). Thus, employees with demands-abilities fit may experience greater job satisfaction and career satisfaction because they try to enhance or maintain their organizational self-esteem (Ashforth & Mael, 1989;Cable & DeRue, 2002). Hall's (1971) career development model suggested that increased self-esteem results in greater job involvement. Thus, enhanced self-esteem of employees with demandsabilities fit is expected to lead to increased job involvement.
Based on the reasoning and empirical evidence, Hypotheses 1a and 1b, and proposition III of work adjustment theory (Dawis & Lofquist, 1984), stating that satisfaction is determined by the fit between an employee's values and abilities and the environment's values and ability requirements of the workplace, this study hypothesized that the proactive personality-work outcome relationships would be indirect, mediated through employees' perception of P-J fit and P-O fit. Specifically, proactive personality enhances employees' P-J fit and P-O fit, which then influence job satisfaction, career satisfaction, and job involvement. Accordingly, this study developed the following hypotheses.
Hypothesis 2a: P-J and P-O fits will be positively associated with job satisfaction and mediate the relationship between proactive personality and job satisfaction. Hypothesis 2b: P-J and P-O fits will be positively associated with career satisfaction and mediate the relationship between proactive personality and career satisfaction. Hypothesis 2c: P-J and P-O fits will be positively associated with job involvement and mediate the relationship between proactive personality and job involvement.
The hypothesized model is illustrated in Figure 1.

Data Sources
This study used two independent samples to test the hypothesized model. Data from Sample 1 were collected using a cross-sectional survey, that is, all variables were collected at one time point and were used to test the mechanism linking proactive personality to job satisfaction and career satisfaction. Although collecting data using a cross-sectional survey is relatively easy, it may introduce a common method bias. To reduce common method bias, data from Sample 2 were collected at two time points (Podsakoff et al., 2003). Because employees' job involvement is very important for both employees and organizations, and limited research has examined the linkage between proactive personality and job involvement, except job satisfaction and career satisfaction, this study added one more outcome variable, job involvement, in Sample 2. Analysis of Sample 2 sought to replicate the findings in Sample 1 to enhance the credibility of this study's conclusion and identify the mechanism linking proactive personality to job involvement to extend the findings of the analysis conducted with Sample 1 (Wu & Chi, 2020). The details of Samples 1 and 2 are described in the following two paragraphs.

Sample 1
The author invited 25 organizations located in Taiwan to join this study. Seventeen were service organizations, including nine retailers, one restaurant, two universities, three banks, one insurer, and one hospital, and eight were manufacturing organizations, including one food packaging material manufacturing company, one industrial computer manufacturing company, one petrochemical manufacturing company, one semiconductor chip manufacturing company, one silicon chip manufacturing company, one receipt printer manufacturing company, one notebook manufacturing company, and one fabric manufacturing company. After 25 organizations' senior managers agreed to participate in this study, trained coordinators distributed and gathered the questionnaires. Personnel secretaries in each organization assisted the coordinators in identifying and inviting participants to participate. The coordinators distributed 318 questionnaire copies to the participating organizations. Each participant received an envelope with a questionnaire and a cover letter assuring them that their participation is voluntary and their information will remain anonymous. The participants completed the questionnaires and returned them to their organization's personnel secretaries. Three weeks after the initial invitation, 307 questionnaires were gathered and sent back to the author. The final Sample 1 comprised 278 participants after excluding incomplete questionnaires.
Of the 278 participants, 47.8% were male, 72.6% had junior college or university degrees, and 75.2% were operatives. These participants had an average age of 34.18 years (SD = 9.87) and an average tenure of 88.04 months (SD = 101.28).

Sample 2
The data from Sample 2 were collected at two time points to reduce common method bias, and the questionnaires distributed at Time 1 were sealed in two separate envelopes (Podsakoff et al., 2003). The first envelope contained information on employees' gender, age, organizational tenure, education, position, and proactive personality. The second envelope contained information on employees' P-J and P-O fits. Time 2, 1 month after Time 1, measured employees' job satisfaction, career satisfaction, and job involvement. To collect data from Sample 2 participants, the author invited 22 organizations in Taiwan to join this study. Eight were service organizations, including one hospital, one estate agent, one publisher, two retailers, one insurer, one logistics, and one accounting. Fourteen were manufacturing organizations, including one light-emitting diode manufacturing company, one internet access devices manufacturing company, one integrated circuit manufacturing company, one lathe manufacturing company, one notebook manufacturing company, one ceramics manufacturing company, one silicon chip manufacturing company, one industrial paper manufacturing company, one swimming goggles manufacturing company, two electric power equipment manufacturing companies, one monitor manufacturing company, one industrial computer manufacturing company, and one cement manufacturing company. Questionnaires were assigned the same codes at Time 1 and Time 2 to allow matching the data. With the permission of the participating organizations' senior managers, the author's research assistant distributed and collected the questionnaires. Each participating organization's personnel secretaries assisted the research assistant in identifying and inviting the participants. The research assistant distributed 346 copies of questionnaires to the participating organizations at Time 1. The participants completed the questionnaires and sent them back to their corresponding personnel secretaries. A total of 338 questionnaires were gathered and sent back to the author by the research assistant. The final sample of Time 1 comprised 323 remained after excluding incomplete questionnaires; therefore, at Time 2, 323 questionnaire copies were distributed to the participating organizations. At each time point, the questionnaire came with a cover letter ensuring the participants that their participation is voluntary and data are anonymous. After Time 2, 318 questionnaires were gathered and sent back to the author by the research assistant. The final Sample 2 comprised 300 participants after excluding incomplete questionnaires.
Of the 300 participants, 57.7% were male, 62.4% had junior college or university degrees, and 78.0% were operatives. These participants had an average age of 35.51 years (SD = 10.56) and an average tenure of 93.70 months (SD = 105.49).

Measures
All the measures were created in English. A standard translation and back-translation process was utilized to ensure the equivalence of the measures in Chinese and English (Brislin, 1980). The response options all ranged from 1 ("strongly disagree") to 5 ("strongly agree").
Proactive personality. Seibert et al.'s (1999) 10-item version was used to measure proactive personality. A sample item is, "I am constantly on the lookout for new ways to improve my life." Scale reliabilities were .80 and .82 for Samples 1 and 2, respectively. P-J fit. This study used Saks and Ashforth's (2002) four-item scale to assess employees' perception of P-J fit. A sample item is, "My knowledge, skills, and abilities match the requirement of my job." Scale reliabilities were .81 and .83 for Samples 1 and 2, respectively. P-O fit. Saks and Ashforth's (2002) four-item scale assessed employees' perception of P-O fit. A sample item is, "The values of my organization are similar to my values." Scale reliabilities were .85 and .84 for Samples 1 and 2, respectively.
Job satisfaction. Job satisfaction was assessed with two items that reflect overall job satisfaction. Tekleab et al. (2005) utilized this two-item scale from Dunham and Smith's (1979) Index of Organizational Reactions. A sample item is, "All in all, I am satisfied with my job." Scale reliabilities were .82 and .80 for Samples 1 and 2, respectively. Martins et al.'s (2002) three-item scale. A sample item is, "In general, I am satisfied with my career status." Scale reliabilities were .83 for both Samples 1 and 2.

Career satisfaction. This variable was measured with
Job involvement. Job involvement was measured with four items selected from Kanungo's (1982) 10-item scale with a factor loading of at least .49 for both times in Blau's (1985) study. The four items are, "The most important things that happen to me involve my present job," "I live, eat, and breathe my job," "Most of my interests are centered around my job," and "I consider my job to be very central to my existence." This research did not collect data on job involvement for Sample 1. For Sample 2, the scale reliability was .86.

Data Analysis
This study used AMOS 6.0 to conduct confirmatory factor analysis (CFA) to test variables' distinctiveness in Samples 1 and 2. The hypothesized model's fit was compared with several alternative nested models.
After clarifying variables' distinctiveness in Samples 1 and 2, this study used hierarchical linear modeling (HLM; Bryk & Raudenbush, 1992) to test this study's hypotheses. As 278 participants in Sample 1 and 300 participants in Sample 2 were nested in 25 and 22 organizations, respectively, these participants were not independent (Anand et al., 2010). This study used some null models without any predictors to calculate the Level 1 (individual-level) and Level 2 (organization-level) variances for Samples 1 and 2. For instance, for Sample 1, job satisfaction's individual-level variance was .468 and organization-level variance was .083. The ratio of organization-level variance to total variance indicated an intraclass correlation coefficient (1) (ICC(1)) of .151, showing that for Sample 1, 15.1% of job satisfaction's total variance was ascribed to an organization membership effect. In addition, in Sample 1, the ICC(1) value for career satisfaction was .208, and in Sample 2, the ICC(1) values for career satisfaction, job satisfaction, and job involvement were .181, .183, and .171, respectively. Those ICC(1) values indicated this study could use HLM to control and model the effects of organization membership in both samples when testing the hypotheses (Bliese, 2000).
In this study, Level 1 independent variables were centered on the grand mean for Samples 1 and 2 (Hofmann & Gavin, 1998). Following Anand et al. (2010), to control the influences of the between-organizations variations on Level 1 dependent variables for both samples, this study modeled random effects for Level 2 intercept and fixed effects for Level 2 coefficients except the intercept. To compare different models and report effect size for both samples, this study used full maximum likelihood estimation to perform deviance tests, and the results are presented based on the generalized least squares (GLS) standard errors (e.g., Anand et al., 2010). In addition, the conditions recommended by Baron and Kenny (1986) and the Sobel test were applied in this study to test mediation. Table 1 demonstrates the results of CFA that examined the variables' distinctiveness for Sample 1. As demonstrated in Table 1, the fit indexes indicated that the hypothesized fivefactor model fits the data better than any other alternative nested models. This result supports the constructs' distinctiveness. As Table 1 shows, for instance, the fit indexes of CFA (χ 2 = 519.20, df = 220; incremental fit index [IFI] = .90; comparative fit index [CFI] = .90; root mean square error of approximation [RMSEA] = .07) of the hypothesized five-factor model are significantly better compared with the fit indexes of CFA (χ 2 = 559.80, df = 224; IFI = .89; CFI = .89; RMSEA = .07) of the four-factor Model 6, where job satisfaction was combined with career satisfaction into a single factor. The chi-square difference test was significant (χ 2 [4] = 40.60, p < .01; Farh et al., 2007). Accordingly, this result also shows that job satisfaction and career satisfaction are distinct factors. Table 2 demonstrates the results of CFA that examined the variables' distinctiveness in Sample 2. Except for the fivefactor Model 2 (with job satisfaction combined with career satisfaction to form a single factor), the fit indices showed that the hypothesized six-factor model fit the data better compared with any other alternative nested models. Although the two decimal model fit indices (IFI, CFI, and RMSEA) of the hypothesized six-factor model and the five-factor Model 2 were identical, the chi-square difference test (χ 2 [5] = 14.82, p < .05) showed that career satisfaction and job satisfaction are distinct factors. Accordingly, the above results demonstrated variables' distinctiveness in Sample 2.

Results
Tables 3 and 4 demonstrate the standard deviations, means, and correlations among the study variables and the control variables for Samples 1 and 2, respectively. Tables 5 and 6 summarize HLM results for Sample 1, and Tables 7 and 8 review HLM results for Sample 2.
Only control variables were included in Model 1, whereas control variables and proactive personality were included in Model 2, as shown in Table 5. As indicated in Models 1 and 2 of Table 5, after controlling for the effects of control variables on P-J fit, proactive personality was significantly associated with P-J fit (γ 60 = .46, p < .01). Model 2 had a significantly better fit compared with Model 1, as demonstrated by the test of deviance (χ 2 [1] = 26.95, p < .01). These results supported Hypothesis 1a. Similarly, as Note. IFI = incremental fit index; CFI = comparative fit index; RMSEA = root mean square error of approximation; P-J = person-job; P-O = person-organization. Note. IFI = incremental fit index; CFI = comparative fit index; RMSEA = root mean square error of approximation; P-J = person-job; P-O = person-organization.
p < .01) and P-O fit (γ 80 = .43, p < .01) were significantly related to career satisfaction. The deviance test (χ 2 [2] = 182.14, p < .01) demonstrated a significant improvement in the model fit. Regarding the mediated hypotheses, the results for Models 3 and 6 in Table 6 indicate that the significant relationships between proactive personality and job satisfaction and career satisfaction ceased to be significant when the two mediators, P-J fit and P-O fit, were included in the model. The support for Hypotheses 1a and 1b and the significant relationships between proactive personality and job satisfaction and career satisfaction met two of the conditions for testing mediation. The third condition for testing mediation was also met because the previously significant relationships between proactive personality and job satisfaction and career satisfaction became insignificant when controlling for the two mediators (Baron & Kenny, 1986).

Discussion
The findings of this study on the positive relationships between proactive personality and P-J fit and P-O fit are consistent with previous literature. For example, although Wu and Chi (2020) did not propose a positive relationship between proactive personality and P-O fit, their data indicated that proactive personality is positively associated with P-O fit. Theoretically, these findings are in line with Dawis and Lofquist's (1984) work adjustment theory, which posits that individuals' basic motivation in their work is to seek a congruence between the work surroundings and their characteristics. In addition, these findings are also aligned with the literature on proactive personality (e.g., Bateman & Crant, 1993;Crant, 1995;Seibert et al., 1999), which suggests that proactive individuals, compared with their passive counterparts, are more likely to take actions to create or seek work environments that fit their needs and values. Accordingly, this study verified the underlying theory and provided empirical evidence supporting the positive relationships of proactive personality with P-J fit and P-O fit.
This study revealed significant mediating effects of P-J and P-O fits on the relationships of proactive personality with job satisfaction, career satisfaction, and job involvement. These findings are consistent with the previous literature; for example, Jawahar and Liu (2017) found a positive association between proactive personality and career satisfaction, while Yen et al. (2019) reported a positive association between P-J fit and career satisfaction. Although previous literature has indicated that proactive personality is positively associated with job satisfaction (e.g., Liao, 2015) and career satisfaction (e.g., Jawahar & Liu, 2017), from the perspective of person-environment fit, this study expanded upon the previous literature and revealed the mechanism linking proactive personality with job satisfaction, career satisfaction, and job involvement. Specifically, this study found that proactive personality enhances P-J fit and P-O fit, leading to increased job satisfaction, career satisfaction, and job involvement. This mechanism is in line with work adjustment theory's (Dawis & Lofquist, 1984) third proposition that an individual's satisfaction is a function of the extent of the fit between the work and individual requirements. In addition, the findings linking proactive personality to job involvement provide new insight into the literature, suggesting that proactive employees, compared with passive employees, tend to be more involved in their jobs and that the influence of proactive personality on job involvement is indirect, operating through the mediating influences of P-J fit and P-O fit. Moreover, the findings of the positive relationships between both P-J and P-O fits and job involvement extend Dawis and Lofquist's (1984) third proposition and suggest that person-environment fit would lead to not only increased satisfaction but also increased job involvement.

Theoretical Implications
This study on the mediating influences of P-J and P-O fits on the relationships between proactive personality and job satisfaction, career satisfaction, and job involvement contributes to the literature on proactive personality and work adjustment in three ways. First, our study indicated that proactive personality is positively related to both P-J fit and P-O fit. This result supports evidence that proactive personality is an important antecedent of both P-J fit and P-O fit. Second, P-J and P-O fits significantly mediated the relationships of proactive personality with job satisfaction, career satisfaction, and job involvement. This result verified the work adjustment theory's (Dawis & Lofquist, 1984) third proposition that an individual's satisfaction is determined by the extent of the fit between this individual's characteristics and his or her work environment. Third, this study extends the third proposition of the work adjustment theory (Dawis & Lofquist, 1984), concluding that P-J fit and P-O fit influence not only satisfaction but also job involvement.

Implications for Managers
This study has two implications for managers. The first is that the positive relationships of proactive personality with P-J fit and P-O fit have implications for hiring proactive employees. For example, managers may use Bateman and Crant's (1993) 17-item scale to assess candidates' proactive personalities and then hire proactive individuals. The other implication is that because P-J fit and P-O fit fully mediate proactive personality's influences on career satisfaction, job satisfaction, and job involvement, managers can implement managerial practices to enhance employees' P-J fit and P-O fit to prevent the negative indirect effect of less proactive personalities on job satisfaction, career satisfaction, and job involvement. For example, organizational socialization refers to the process through which employees acquire appropriate attitudes, learning, and behaviors to adjust to the new role in their jobs (Chong et al., 2021;Van Maanen & Schein, 1979). Jones (1986) suggested that organizational socialization tactics may influence newcomers' adjustments to their organizations. Furthermore, Cable and Parsons (2001) reported that organizational socialization tactics, such as providing newcomers with clear information about the succession of activities they will experience in the new surroundings and senior organizational members acting as mentors for newcomers, are positively associated with P-O fit. In addition, Boon et al. (2011) revealed that a set of human resources practices, such as training and development, performance appraisal and rewards, teamwork and autonomy, work-life balance, and recruitment and selection, are positively related to P-J and P-O fits. Since not all employees are proactive, managers can implement those socialization tactics and human resources practices to increase employees' P-J and P-O fits to prevent the negative indirect effects of employees' passive personality on job satisfaction, career satisfaction, and job involvement.

Limitations and Suggestions for Future Study
The following limitations of this study should be acknowledged and considered in future studies. First, to reduce potential single-source bias, the data for Sample 2 were collected at two separate time points; the questionnaires assessing proactive personality and the mediators (P-J fit and P-O fit) at Time 1 were sealed in separate envelopes (Podsakoff et al., 2003). However, in future studies, employees' parents, spouses, or friends may be asked to rate employees' proactive personalities to prevent single-source bias. Second, this study used P-J and P-O fits as mediators on the relationships between proactive personality and job satisfaction, career satisfaction, and job involvement. The results indicated that P-J fit and P-O fit significantly mediated the relationships between proactive personality and outcome variables. As this study did not consider other person-environment fit variables, such as person-supervisor fit and person-group fit, as mediators, future studies may include these variables to examine whether person-supervisor fit and person-group fit mediate the relationships between proactive personality and work outcomes. Third, this study did not test the reciprocal relationship of proactive personality with P-J fit and P-O fit. However, Li et al.'s (2014) study revealed that proactive personality is associated with changes in work characteristics, which are further associated with changes in proactive personality. Therefore, future research should examine whether proactive personality increases P-J fit and P-O fit and whether these fits are positively associated with proactive personality. Fourth, this study did not test the potentially detrimental effects of proactive personality on employees' wellbeing. However, Crant et al. (2017) indicated that a proactive personality might harm an individual's well-being. Similarly, Sun et al.'s (2021) study revealed that individuals with a proactive personality might receive less help and more social undermining from coworkers. Hence, future study is encouraged to investigate the unknown positive effects and the unknown negative effects of proactive personality on wellbeing. Fifth, this study did not control for the potential effects of organization-based self-esteem. However, Bowling et al.'s (2010) meta-analysis indicated that organization-based selfesteem is positively related to job satisfaction and job involvement. Future research should control for the effects of organization-based self-esteem on job satisfaction, career satisfaction, and job involvement.

Conclusion
This study was the first to use the work adjustment theory to link proactive personality and individuals' job satisfaction, career satisfaction, and job involvement. It also developed a model to explain how and why proactive employees are more likely to achieve higher career satisfaction, job satisfaction, and job involvement. The findings of this study indicated that proactive personality enhances P-J and P-O fits, and these fits significantly mediate the relationships between proactive personality and career satisfaction, job satisfaction, and job involvement. Proactive employees are more likely compared with passive employees to create a work environment congruent with their characteristics, resulting in increased job satisfaction, career satisfaction, and job involvement. This study and its results make important contributions to theory and practice.

Declaration of Conflicting Interests
The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding
The author disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by a grant from the Ministry of Science and Technology in Taiwan