The Mediating Role of Social Capital in Islamic Work Ethic, Organizational Commitment, and Lecturer’s Performance

The success of higher educations in producing intelligent, noble, skillful, and selfdeveloping graduates with good personality to improve the nation’s competitiveness in globalization era is very much determined by lecturer’s performance. However, various problems in the performance hamper the advancement of higher educations, especially private Islamic ones. The poor implementation of Tridharma Perguruan Tinggi (tree role of higher education), particularly in research, public service, and writing scientific paper’s, not to mention moonlighting behavior, must be enhanced through accurate problem identification and countermeasure. This study tries to measure the influence of Islamic work ethic and organizational commitment on lecturer performance, identify the mediating role of social capital on the influence of work satisfaction, and determine the moderating effect of Islamic work ethic on the relation between lecturer‘s performance on their satisfaction. This study uses data from 236 lecturers, selected through random sampling technique, of grade-A private Islamic higher educations. Using WarpPLS 5.0, the results of the analysis show that Islamic work ethic and organizational commitment plays a significant role in improving lecturer’s performance. Although, social capital is not significant to the performance, it partially mediates the influence of Islamic work ethic and organizational commitment to the performance. In addition, organizational commitment partially mediates the influence of Islamic work ethic on the performance. To improve this study, following researches on private Islamic higher educations of lower grades will be beneficial.


INTRODUCTION
There are many researches discussing employee performance due to its sexiness. Many parties believe that the success of an organization is basically determined by employee performance. It means that the better the employee performance, the better the performance of the company or organization (Dessler, 2011). Researchers have attempted to analyze employee performance by linking it to factors allegedly influence it. Tett et al. (1991); Barrick and Mount (1991); Bakker et al. (2012); Zhao et al. (2010) analyzed performance by relating it to employee personality and aspects around it. Tett and Meyer (1993); Khan et al. (2010a); Jaramillo et al. (2005); Yousef (2000); Huey et al. (2009) related performance to satisfaction, organizational commitment, organizational culture, and employee turnover. Other researchers related employee performance to motivation (Hayati and Caniago, 2012;Bright, 2007;Orpen, 1997;Walker Jr et al., 1977), performance to leadership and work satisfaction (Wong and Laschinger, 2013;Braun et al., 2013;Wood et al., 2012), not to mention other numerous researches in employee performance. Based on research location, analyses on employee performance are mainly held in business organizations, profit-oriented institutions, and non-profit institutions such as governmental institutions.
However, there is still a limited number of researches that discuss employee performance using higher education as the research location and lecturers as the research subject, especially private higher education in Indonesian context. There are 631 private higher education in Indonesia, from which 53% is in Java, and the rest is scattered in several provinces. Most private higher education in Indonesia are affiliated to Islamic organization such as Nahdlatul Ulama and Muhammadiyah. This phenomenon is a great potential for the establishment of Indonesian civilization idealized by Islam, which is baldatun thoyyibatun wa rabbun ghaffur, a nation whose people are safe, peaceful, and prosperous; the dream of mankind (Hasan, 2015).
From the establishment aspect, many private higher educations were founded by spiritual leaders (ulama), and some of them were even established in pondok pesantren (Islamic boarding schools in Indonesia) (Suprayogo, 2012). In the context of Indonesia, whose majority of its people are Muslim, the role of ulama in developing the society is very strong and strategic (Faridl, 2007). There are many cases where ulama in Indonesia are referred in decision and policy making, especially by the government regarding issues dealing with the development of Islamic character building in the society, which is the responsibility given to education world. This is the social capital owned by individuals who are working in the education institutions. Hasan (2015) stated that one of the objectives of Islamic higher education is to produce graduates with intellectual and spiritual competence, so they are able to develop the society and to orient their activities toward Allah SWT. This conforms to the basic teaching about the reason behind the creation of human as described in the Quran, surah Al-Dhariyat verse number 56, saying "And I did not create the jinn and mankind except to worship Me." This objective can only be met by using educators (lecturers) who understand and are able to apply Islamic behavior in their job especially in the teaching process, which later on in the formulation of this study is called as Islamic work ethic.
Based on the description above, the objective of this study on private higher educations is to assess the mediating influence of social capital on the influence of Islamic work ethic and knowledge sharing on the performance of lecturers. Stackhouse (1995) defined work ethic as "… the basic belief that a person should do work that has some basic moral worth and that every person should do his or her very best, irrespective of reward." Cherrington (1980) defined work ethic as "… Cultural norm that advocates being personally accountable and responsible for the work that one does. It is based on belief that work has intrinsic value to the individual." Based on the two definitions, it can be concluded that work ethic is the fundamental faith or principles used by people as a guidance in doing their jobs.

Islamic Work Ethic
In islamic point of view, working is a noble deed, because through which a Muslim is perceived to have kept his pride and dignity (Suprayogo, 2012). In addition, people who are working, who try to get income to provide for themselves and their families by using their own hands, will get a noble predicate because, besides acquiring material income, they earn pahala. There are many stories that encourage and motivate Muslim to work hard. Islam categorizes people who work hard as jihad fi sabilillah. This is based on a story of Ka'ab bin Umrah:  Al-Albâni, 1996).
Thus, working in Islam is very noble. Islam highly appreciate people who work. Islam even believes that when a person feels tired after working, Allah gives mercy on his sins straight away. Ibnu Abbas RA said: "I heard Rasulullah SAW said, those who feels tiredness in the afternoon after the work using his hands, his sins will be erased by Allah SWT in that afternoon ." In another hadith, it is stated working can erase sins that cannot be erased by salat, sawm, hajj, and umrah. Abu Hurairah RA said that Rasulullah SAW said that: "Among those sins is a sin that cannot be forgiven by salat, sawm, hajj, and umrah." The sahaba asked. "Then, what can erase it, o Rasulullah?" He answered, "The passion to look for rizq (working)." (Hadith from Thabrani in Al-Mu'jam Al-Ausath I/38). Therefore, Islam highly appreciate people who want to work hard to get income. Sastrahidayat (2009);Suprayogo (2012) even stated Islam perceived working as an obligation for every Muslim. Through working, a person can express his self as the most perfect being created by Allah SWT and can be beneficial to the society around him. This is the orientation of working in Islam, which is not only a search for wealth but also a form of ibadah to Allah SWT reflected in the benefit received by human at large. Thus, Islam categorized working as ibadah, as commanded by Allah SW in surah At-Tawbah verse number 105: And say (O Muhammad), "Do deeds! Allah will see your deeds, and (so will) His Messenger and the believers. And you will be brought back to the All-Knower of the unseen and the seen. Then He will inform you of what you used to do." Work ethic in Islam is based on the teaching of Islam sourced from the Quran and Al Hadith (Ali and Al-Owaihan, 2008;Kamaluddin and Manan, 2010;Owoyemi, 2012) as mentioned above. Islamic work ethic serves as a guidance for Muslims in living their lives, particularly those related to work. Several dimension related to Islamic work ethic give guidance in intention (motivation) to work, choosing a job, behavior at work, and attitude in accepting the work result (Tafsir Alqur'an Tematik, 2010). In this study, the indicators used to analyze islamic work ethic are niyyah (motivation) to work, ikhlas (sincerity) in working, amanah (trustful), tawakkal (putting trust in Allah regarding the gain from work), istiqamah (steadfastness in working, which is being consistent between faith, what is spoken, and what is done), itqan (professionalism in working), and qana'ah (remain contented). Mowday et al. (2013) defined organizational commitment as individual identification strength in an organization through a strong will to become the best organization member through total involvement and persistent work based on the acceptance of the values and the objectives of the organization. Thus, it can be concluded that organizational commitment is high sense of belonging, involvement, responsibility, and loyalty of employees to their organization. Curtis and Wright (2001) mentioned that the organizational commitment dimension has three components; they are (1) the willingness to maintain membership in an organization, (2) the faith on and the acceptance toward organizational values and objectives, and (3) the willingness to work hard as a part of an organization.

Organizational Commitment
In general, Zurnali (2010) mentioned that studies about employees who have a strong affective commitment stay in the organization because they want to remain bound and be loyal to the organization both emotionally and psychologically. Meanwhile, employees who are said to have a strong continuance commitment stay in the organization because they have to stay in the organization and remain a part of it based on profit-loss considerations. Finally, employees are said to have a strong normative commitment if they stay because they feel they have to do so due to feeling reflection of responsibility to remain a part of the organization.
Meyer and Allen (1991), Meyer et al. (2002) stated that organizational commitment is a "good" psychological condition, characterizing the relationship between employee and organization that influences the sustainability of the employee in the organization. It can be identified through three components; they are (1) affective commitment, i.e., the emotional involvement of a person to his organization in a form of love to his organization, in which the indicators are feeling happy in the organization and become loyal to the organization, (2) continuance commitment, i.e., the perception of a person about the cost and risk coming from his departure from the current organization, which means that there are to aspects in continuance commitment: Involvement personal give up in departing the organization and the absence of alternative for the person departing the organization, in which the indicators are calculating the benefit of staying and calculating the loss of leaving, (3) normative commitment, i.e., a moral dimension based on sense of responsibility, in which the indicators are the willingness to work and the responsibility to improve the organization.
The measurement of organizational commitment in this study is based on indicators developed by (Mowday et al., 1979); they are (1) the willingness to maintain membership in an organization, (2) harmony with organizational values and objectives, and (3) seriousness in working. Fischer et al. (2004) stated that the concept of social capital was introduced by Lyda Judson Hanifan in 1916, who mentioned that the substantial factors in real communal life are goodwill, sympathy, friendship, and social interaction that create a social unit. In its development, the social unit is understood as social capital that is categorized as a capital because there are resources in it that can be invested and expected to yield something for various objectives (Kilpatrick and Bell, 2000).

Social Capital
However, the definition and terminology of social capital are different from those of human capital (Fukuyama, 1996). The forms of human capital are "knowledge" and "skill" of human. The conventional human capital investment is in form of things similar to education in university, mechanic or computer programmer training, or other appropriate education establishment, while social capital is the capability appearing from public trust in a society or certain parts of it. Social capital can be institutionalized in the smallest or the most basic form of social groups as well as in the largest social groups such as country (nation).
Social capital is transmitted through cultural mechanisms, such as religion, tradition, or historical custom (Fukuyama, 2001). Social capital is needed to create moral society that cannot be obtained in cases of human capital forms. Acquisition of social capital needs some adjustments toward moral norms of a society and at the same time, in its context, adopts virtues. Burt (1997) stated that this association ability really depends on a condition where the society is willing to share in the efforts of finding the meeting point among common norms and values. If this ethical-normative meeting point is achieved, individual interests will in turn comply with communal interests, such as loyalty, honesty, and dependability. Social capital is founded more on general social virtues. Dasgupta and Serageldin (2001) believe that social capital is something referring to institutional dimensions, created relationships, and norms that determine the quality and the quantity of social relationship in a society. Social capital is not merely a numeric series of institutions or groups that underpin social life. Its spectrum is wider, in which it serves as social glue that maintain the unity of group members.
The dimension of social capital grows in a society, in which it contains values and norms as well as social interaction patterns in arranging the daily lives of its members (Woolcock, 1998). Therefore, Adler and Kwon (2002) stated that social capital dimension is the depiction of internal attachment that colors a collective structure and provides cohesiveness as well as mutual benefit from social dynamic process taking place in the society.
The dimension of social community depicts all things that make the society create a coalition to achieve common objectives based on togetherness, in which it is bound by growing and complied values and norms (Dasgupta and Serageldin 2001). This dimension is inherent in social relation and social network structure in a society, which brings in various social obligation, creates mutual trust climate, carries information channel, and sets up social norms and sanctions for the member of the society (Coleman, 1988).
Nevertheless, Fukuyama (2001) strictly stated that norms and values accepted as the reference in determining attitude and behavior do not necessarily and automatically become social capital. Instead, they are only common norms and values raised by trust, where trust here is expectation toward order, honesty, and cooperative behavior appearing from the inside of a societal community based on norms commonly applied by its members. The norms contain statements around noble (virtue) and justice values.
Based on the existing conceptions, an understanding can be drawn that the dimension of social capital emphasizes more on the togetherness of the society to achieve the objective of improving their life quality and continuously changing and adapting. In the process of changing and trying to achieve the objective, people are always bound to values and norms accepted as a guidance to behave toward, to have relationship with, and to create network with other parties.
Several value references and components that become the spirit of social capital are participative attitude, mutual concern, mutual exchange, and mutual trust, strengthened by supporting values and norms. Another component that plays an important role is the willingness of the society to be continuously proactive in maintaining values, establishing cooperation network, and creating new ideas. This is the real identity of social capital. Therefore, Hasbullah (2006) stated that the core dimension of social capital lies on how the society is able to cooperate in establishing a network to achieve mutual objectives. The cooperation is colored with a reciprocal and beneficial interrelation pattern built on trust supported by positive and strong social norms and values. The strength will be maximum if it is supported by proactive spirit to create relationships upon participative attitude, mutual concern attitude, mutual exchange, and mutual trust principles strengthened by the supporting values and norms.
In the discussion about social capital in educational context, Mohammad (2012) stated that the broader the social network of person, the higher his opportunity to exchange knowledge, technology, expertise, and other benefit. In addition, his opportunity to improve his performance is also higher. An educator that has a wide network is easier to get support for his colleagues and has a better opportunity to improve his performance.
Further, Mohammad (2012) defined network bond as the number and form of cooperation that are done and spark hope of knowledge/technological exchange, or any other form of exchange. The network configuration describes the way and the mechanism of how the cooperation is built and determines who the initiator is, so the condition of the knowledge creation and exchange can be seen. The organization involved is organization or cooperation actor that participates in the network. Leana (2010) asserted that, in order to create a high learning environment that makes way to information and scientific exchange among the academicians in the educational institution, the presence of social capital in the management of the educational institution becomes important. Although the educational institution has academically sufficient human capital, if individuals in the institution do not have a good social capital, it is likely that the exchange of information and technology among the academicians, especially educators, in the institution might not happen, so knowledge is accumulated on certain people, which they obtain from individual learning process. Putnam (1993) stated that social capita "… features of social organization such as trust, norms, and networks that can improve the efficiency of society by facilitating coordinated actions," so mutual trust and obedience to the existing social norm as well as established social network that can improve the efficiency of the society are the bases of social capital that present in various social organization. Woolcock (1998) defined social capital as "… the information, trust, and norms of reciprocity inhering in one's social networks," so the good social attributes are information being built and used, mutual trust being fostered, and norms of giving and serving each other. The essence is the spirit to grow together, which is the essence of a social capital that can be established.
Specifically, OECD (2001) defined social capital by stating that "Social capital is networks together with shared norms, values and understandings that facilitate cooperation within or among groups." Therefore, social capital is no other that an organizational network built on common norms with value systems and common understanding about what can strengthen long term cooperation and organizational cohesion.
In this study, social capital in question is individual social capital characterized by ownership of intra and extra organizational network, trust, and shared goal. Koopmans et al. (2011) defined individual performance as a record of results gained from certain work functions or activities in a certain time. According to behavioral approach in management, performance is the quantity or quality produced or service provided by a person who work (Luthans, 2010). Mathis and Jackson (2006) stated that performance is basically what is or is not done by an employee.

Performance
Factors that affect performance, according to Mathis and Jackson (2006) are as follows. a. Effectiveness and efficiency. If a certain objective can finally be achieved, we may say that the activity is effective. However, if unwanted consequences appearing from the activity, despite the result that creates satisfaction and effective assessment, are important, the activity is inefficient. On the contrary, if the unwanted consequences are not important or insignificant, the activity is efficient. b. Authority. It is a communication or command in a formal organization owned by a member of an organization applicable to the other members of the organization to carry out a work according to their contribution. The command tells what one may or may not do in the organization. c. Discipline. It is the obedience to applicable law and regulation.
Thus, employee discipline is the activity of the employees of respecting the work arrangement with the organization where they work. d. Initiative. It deals with thinking capability and creativity in shaping ideas to plan anything about the objective of the organization.
In connection to employee performance indicator, Robbins (2006) asserted that to measure the performance of employees individually, six indicators were used. They are: 1. Quality. It is measured from the perception of employees about the work quality he produces and the accomplishment of his task against his skill and capability. 2. Quantity. It is the number of an employee's production, expressed in unit or number of accomplished activity cycle. 3. Punctuality. It is the ability to finish an activity before the due time, which is seen from the angle of coordination and output to maximize the time available to do other activities. 4. Effectiveness. It is the level of organizational resource usage (power, money, technology, and raw material), which is maximized to increase the result of each unit. 5. Independence. It is the level where an employee can implement his working function in the future. 6. Commitment. It is the level where an employee is committed to work with an institution and responsible to his work place.
In the context of lecturer profession, performance is measured by considering handbook for lecturer's workload and evaluation of tridharma perguruan tinggi (Indonesian term for obligations of higher education) implementation issued by Directorate General of Higher Education in 2010 in respect to the following aspects. 1. Education and teaching. The task of carrying out education and teaching involves (1) carrying out lectures/tutorials and their assessment, carrying out educational activities in laboratory, teaching practice, practices in workshop, studio, experimental plantation, and teaching technology, (2) advising student seminar, (3) supervising internship, apprenticeship, and fieldwork, (4) advising student's research and final report preparation, (5) assessing in final examination, (6) supervising student's activity in academic and student affairs, (7) developing course program, (8) developing course material, (9) delivering scientific oration, (10) counselling lower-rank lecturers, (11) carrying out lecturer secondment. 2. Research. This task covers (1) producing research work, (2) translating and adapting scientific books, (3) editing scientific works, (4) making technological design and work, (5) making artwork design. 3. Public service. This includes (1) taking a leadership in the government, so organic position must be relinquished, (2) implementing the result of education and research for public use, (3) giving training, counseling and upgrading to society, (4) providing service for the public or carrying out other activities that support governmental task and development, (5) writing a paper in public service.
4. Supporting activities. These include (1) becoming a member of a committee or a board in higher education, (2) becoming a member of a committee or a board in governmental institution, (3) becoming a member of a professional organization, (4) representing a higher education or governmental institution in inter-institution committee, (5) becoming the member of national delegation in international meeting, (6) being active in scientific meetings, (7) earning awards, (8) writing course books for high school or lower level, (9) receiving achievement in sport, art, or social.

Islamic Work Ethic, Organizational Commitment, Social Capital, and Performance
The relation between Islamic work ethic and social capital, especially social capital in individual limit is basically strong. In the dimension of working attitude and the usage of work result in work ethic, Islam teaches principles of amanah (trustful), itqan (professional/perfect), istiqamah (steadfast, consistent between faith, what is spoken, and what is done) (Tafsir Alqur'an Tematik, 2010). In addition, Islam also teaches the principle of ta'awun (helping each other) among Muslim in kindness. In connection to social capital, those teachings are the key points in developing social capital dimensions, such as mutual trust, network, and shared goal development. However, research about the role of Islamic work ethic in the formation of social capital has not been done by previous researchers, while the results of studies examining the influence of Islamic work ethic on performance have proven that Islamic work ethic gives positive and significant results (Abbasi et al., 2012;Abdi et al., 2014;Imam et al., 2013;Hayati and Caniago, 2012). Thus, the first, second, and third hypotheses of this study are: H 1 : Islamic work ethic has a positive and significant effect on social capital H 2 : Islamic work ethic has a positive and significant effect on performance H 3 : Islamic work ethic has a positive and significant effect on organizational commitment.
Based on the three hypotheses above, it can be presumed that the application of Islamic work ethic has a positive and significant influence on social capital, organizational commitment, and performance.
A person who has a strong commitment to the organization is basically a capital for the organization to improve its performance. Likewise, individuals who are committed to the organization will gain the trust of the members and the environment of the organization because his commitment to the organization is the guarantee about his willingness to fight for the goals and objectives of the organization. Several studies that examine the relation between organizational commitment and performance show positive and significant results (de Araújo and Lopes, 2014; Becker et al., 1996;Hayati and Caniago, 2012). Thus, the fourth and fifth hypotheses of this study are: H 4 : Organizational commitment has a positive and significant effect on social capital H 5 : Organizational commitment has a positive and significant effect on performance.
Based on the two hypotheses above, it can be expected that individuals who have a strong commitment to the organization will have considerable social capital and performance.
The next hypotheses examine the mediating influence of social capital on the relation between Islamic work ethic and organizational performance and between commitment and performance. Thus, the sixth, seventh, and eighth hypotheses are: H 6 : Social capital mediates the influence of Islamic work ethic on performance. H 7 : Social capital mediates the influence of organizational commitment on performance. H 8 : Organizational commitment mediates the influence of Islamic work ethic on performance.
Based on the description above, the framework of this research model is presented in Figure 1.

Sample and Data Collection
The population of this study is lecturers from private Islamic higher educations in Indonesia with A accreditation. The criterion of the sample of this study is permanent lecturers of foundations or civil servant lecturers who are assigned in private Islamic higher educations with minimum functional rank of instructor. Using the criterion, the population of this study is 1711 lecturers. Using Slovin formula at 7.5% error, the sample size is 162 people. 600 questionnaires were distributed random sampling wise, and 254 were returned, and 236 were eligible. Based on collected data, the characteristics of the respondent can be seen in Table 1.

Measurement
Islamic work ethic is measured based on intention (motivation) to work, choosing a job, behavior at work, and attitude in accepting the work result (Tafsir Alqur'an Tematik, 2010). In this study, the indicators used to analyze islamic work ethic are niyyah (motivation) to work, ikhlas (sincerity) in working, amanah (trustful), tawakkal (putting trust in Allah regarding the gain from work), istiqamah (steadfastness in working, which is being consistent between faith, what is spoken, and what is done), itqan (professionalism in working), and qana'ah (remain contented). The measurement scale uses 1-5 Likert scale (1 for strongly disagree, 5 for strongly agree).
Organizational commitment is measured through indicators developed by (Mowday et al., 1979), in which organizational commitment is characterized by acceptance on organizational objectives, seriousness to work for the sake of the organization, and the desire to stay in the organization. The measurement scale uses 1-5 Likert scale (1 for strongly disagree, 5 for strongly agree).
Social capital is measured based on indicators developed by Lin (2008), which include networking, trust, and shared goal among individuals in one lecturer community. The measurement scale uses 1-5 Likert scale (1 for strongly disagree, 5 for strongly agree).
Performance is measured through Indonesian government regulations on lecturers' workloads (Undang-Undang No 12 2012), which includes performance in education and teaching, research, public service, and supporting activities. The measurement scale uses Gutman's scale (1 for yes, 0 for no). The validity test for questionnaires using Guttman scale is done through reproducibility and scalability coefficient test developed by Dunn-Rankin et al. (2014), which specifies that the reproducibility coefficient value should be >0.90 and the scalability coefficient value should be >0.6. Based on these tests, the reproducibility coefficient of the performance questionnaire of this study is 0.912, and its scalability coefficient is 0.761.

Data Analysis
Descriptive analysis is used to provide an overview about the profile of the respondents based on the responses to the questionnaire. Data analysis in this study was conducted using WarpPLS 5. Several analyses related to this research are described as follows.

Measurement Model (Outer Model) Evaluation
Outer model is used to measure the reliability and validity of the indicators that make up the latent variables. For variables with reflective indicators, the measuring instruments used in outer  model evaluation are loading factor, composite reliability, average variance extracted (AVE), and discriminant validity. The result of loading factor analysis is presented in Table 2.
For internal consistency, the reliabilities indicated by the composite reliability of each variable are: Social capital is 0.877, organizational commitment is 0.752, Islamic work ethic is 0.828, and performance is 0.829. Variables are said to meet the composite reliability criteria if the value is >0.7 (Hair 2010).
The value of AVE is used to measure how far the research indicator is able to explain the variables. The recommended value is >0.50 (Fornell and Larcker, 1981). Based on the analysis, the AVE values of the four variables are: Social capital is 0.705, organizational commitment is 0.534, Islamic work ethic is 0.519, and performance is 0.551. Thus, all four variables meet the specified requirements.
In the construct of reflective indicator, in addition to the above criteria, there is one criterion that must be met to see the reliability and validity of the construct, that is by looking at the discriminant validity result. The rule is that the square root of AVE for each construct must be greater than the correlation between the constructs in the model. Based on this requirement, the results of the discriminant analysis are as follows.
Based on Table 3, it can be concluded that all constructs with reflective indicators have met the criteria of discriminant validity (Table 4).
The validity and reliability of the construct with the formative indicator, which in this study is performance, are determined by significant weight, indicated by the result of the indicator weights.
To see collinearity, the VIF value is used. The conditions are P < 0.05 and VIF is <3.3 (Kock, 2015).

Structural Model (Inner Model) Evaluation
Structural model (inner model) evaluation is used to predict the relation between latent variables by looking at the variance that can be explained and by measuring the significance of P value. Some items to note are the R-squared values of each endogenous latent variable that are used to determine the predictive power of the structural model. In addition, the Stone-Geisher test is used to test the predictive relevance, and goodness of fit (GoF) is used to measure the strength of the model as a whole. Based on the data analysis, the fit model and index quality are as follows.

General Model Elements
• Missing data imputation algorithm: Arithmetic mean imputation   To facilitate structural model evaluation, Figure 2, which is the result of data analysis, can be observed.
Based on Figure 2, it can be explained that the percentage of variance (R 2 ) in endogenous latent variables is as follows: Islamic work ethic has a weak influence on organizational commitment because the value of R 2 = 24%; Islamic work ethic and organizational commitment have moderate effect on social capital, which is R 2 of 34%; and Islamic work ethic, organizational commitment, and social capital have moderate effect on performance variable, which is R 2 of 29% (Cohen, 1988), likewise in the adjusted R 2 and predictive relevance (Q 2 ) values. Table 5 provides the complete information. Figure 2 is the result of path analysis and P values that illustrates the effect of exogenous variables on the endogenous variables of this study. The value of path coefficient and P values that describe the influence of each variable can be seen in Tables 6-7. Based on the data in Tables 6-7 it can be concluded that work ethic gives positive and significant influence to social capital (β = 0.34; P ≤ 0.01). This means that individuals with Islamic work ethic in their work have good individual social capital. Thus, this finding supports hypothesis 1. Islamic work ethic also positively and significantly influences organizational commitment (β = 0.49; P ≤ 0.01). This means that individuals with high Islamic work ethic in their work have a better commitment to the organizati on. This proves that hypothesis 2 of this study is accepted. In addition, Islamic work ethic gives positive and significant influence on performance (β = 0.19;    Organizational commitment has a positive and significant influence on social capital (β = 0.33; P ≤ 0.01). Thus, hypothesis 4 is accepted. This means that individuals with high commitment to the organization will have better individual social capital. Similarly, organizational commitment has a positive and significant effect on performance (β = 0.36; P ≤ 0.01). This means that individuals with a good commitment to the organization are able to improve their individual performance. This result supports hypothesis 5.

Hypothesis Testing
Social capital gives no significant effect on performance (β = 0.09; P > 0.01). This result indicates that individuals with good social capital cannot improve their performance, especially in the profession of lecturer, which have different characteristics from other professions in terms of workload, which has been the focus of researches on the effect of individual social capital on performance. Thus, hypothesis 6 of this research is rejected.
The results of the analysis on the mediating role of social capital of this study can be seen in

DISCUSSION
Researches that examine the contribution of Islamic work ethic to individual performance have been done by previous researchers; they are (Abbasi et al., 2012;Abbasi et al., 2011;Abdi et al., 2014;Hayati and Caniago, 2012;Imam et al., 2013). Researches on the influence of Islamic work ethic on organizational commitment have been done by (Abdi et al., 2014;Farsi et al., 2015;Marri et al., 2012). Researches on the effect of organizational commitment on individual performance have been done by (Chen et al., 2002;Hayati and Caniago, 2012;Khan et al., 2010b;Meyer et al., 1989). Nevertheless, the study examining the mediating role of individual social capital on the influence of Islamic work ethic and organizational commitment on lecturer performance has not been found.
The result of this research shows that Islamic work ethic and organizational commitment give positive and significant influence on lecturer performance. This means that individuals who have high Islamic work ethic will have better performance. Islamic teachings stipulate that work is a part of worship, that work must be done with professionalism (itqan), and human must be consistent (istiqamah) between their faith, what they speak, and what they do. Work must also be devoted to worship to Allah SWT, and, in order to be valued as ibadah, the work must be done in the right way, by obeying rules, and with all the strength to meet the targets that have been given. In addition, Islam also teaches about the importance of hard work. In Islamic view, hard work is one form of jihad fi sabilillah. Those teachings are the teachings that are psychologically believed to be able to encourage a person to have a good behavior, to have a good commitment, and, ultimately, to be able to perform well. This means that the impact of ethical behavior in work, based on Islamic work ethic, aside from improving the performance of lecturers, can increase the commitment of lecturers to their institutions.
Likewise, organizational commitment also shows a positive and significant influence on individual performance. Someone who has an organizational commitment, which is shown by his sincerity in working, is believed to be able to improve his performance. However, in this study, individual social capital does not have significant effect on individual performance. Individual social capital, which is indicated by trust, network, and shared goal in lecturers group, is not able to improve performance.
In a discussion conducted by the researcher with several lecturers of the research subjects, it is concluded that the profession of lecturers is different from the profession of company employees in general because the fulfillment of the lecturer's workload is more influenced by internal factors that exist in the individuals, such as motivation, commitment, work ethic, and competence. This is in accordance with Grote (1996), who stated that the level of a person's performance is determined by the competence of the individual in question. This opinion is reinforced by Becker et al. (2001), who stated that personal character, which consists of knowledge, skills, and abilities, directly affects work performance. This is in accordance with UU Nomor 15 (2005), which states that each lecturer should have four competencies consisting pedagogic, professional, personal, and social competence to support the implementation of tridharma perguruan tinggi because these four competencies are the competencies that are used as performance indicators of lecturers as educators and teachers.

CONCLUSION
The findings of this study indicate that Islamic work ethic has a positive and significant influence on organizational commitment and lecturer performance. Furthermore, organizational commitment has a positive and significant influence on the performance of lecturers in private Islamic higher education. Thus, efforts to improve the performance of lecturers of private Islamic higher education can be done through improving the understanding and the implementation of Islamic work ethic and through strengthening the commitment of the lecturers to their institution through various events that are arranged systematically and programmatically.
The establishment of ethical bodies that oversees the implementation of work ethic needs to be done to ensure that ethical conduct in work based on Islamic teachings has actually been implemented by the lecturer. Increased ethical behavior in the faculty environment will also directly increase lecturer's commitment to the institution and improve his performance.