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Volunteer Reliability in Nonprofit Organizations: A Theoretical Model

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Abstract

The reliability of volunteers is a major concern for many nonprofit organizations. To address this problem in more detail, we develop a theoretical model of volunteer reliability based on psychological contract theory. By taking this perspective as a starting point, we explore how individual volunteer characteristics, organizational factors, and sociological developments shape the exchange of inducements and contributions between volunteers and nonprofit organizations. We discuss how these factors can create tensions in the psychological contract and determine the extent to which volunteers behave reliably. As such, we develop a theoretical framework for addressing the reliability problem in volunteer management.

Résumé

La fiabilité des bénévoles est une des premières préoccupations de plusieurs organismes sans but lucratif. Pour traiter de ce problème plus en détail, nous créons un modèle théorique de fiabilité basé sur la théorie du contrat psychologique. En adoptant initialement ce point de vue, nous explorons la façon dont les caractéristiques individuelles des bénévoles, des facteurs organisationnels et les développements sociologiques influencent l’échange d’incitations et de contributions entre les bénévoles et les organismes sans but lucratif. Nous discutons de la façon dont ces facteurs peuvent créer des tensions dans le cadre du contrat psychologique et déterminons dans quelle mesure les bénévoles font preuve de fiabilité. Nous créons ainsi un cadre théorique permettant de traiter du problème de fiabilité dans le contexte de la gestion des bénévoles.

Zusammenfassung

Die Zuverlässigkeit ehrenamtlicher Mitarbeiter ist für viele gemeinnützige Organisationen ein wichtiges Thema. Um ausführlicher auf dieses Problem einzugehen, entwickeln wir ein theoretisches Modell zur Zuverlässigkeit von Ehrenamtlichen beruhend auf der psychologischen Vertragstheorie. Ausgehend von dieser Perspektive untersuchen wir, wie individuelle Eigenschaften der Ehrenamtlichen, organisatorische Faktoren und soziologische Entwicklungen den Austausch von Anreizen und Beiträgen zwischen den Ehrenamtlichen und den gemeinnützigen Organisationen beeinflussen. Wir diskutieren, wie diese Faktoren zu Spannungen im psychologischen Vertrag führen können und ermitteln den Grad der Zuverlässigkeit der Ehrenamtlichen. Dazu entwickeln wir ein theoretisches Rahmenwerk, das das Problem der Zuverlässigkeit im Management der ehrenamtlichen Mitarbeiter angeht.

Resumen

La fiabilidad de los voluntarios es una preocupación de importancia para muchas organizaciones sin ánimo de lucro. Para abordar este problema con más detalle, desarrollamos un modelo teórico de fiabilidad de los voluntarios basado en la teoría del contrato psicológico. Al tomar esta perspectiva como punto de partida, exploramos cómo las características individuales del voluntario, los factores organizativos, y los desarrollos sociológicos dan forma al intercambio de incentivos y contribuciones entre voluntarios y organizaciones sin ánimo de lucro. Tratamos cómo estos factores pueden crear tensiones en el contrato psicológico y determinar la medida en que los voluntarios se comportan de manera fiable. Como resultado, desarrollamos un marco teórico para abordar el problema de la fiabilidad en la gestión de voluntarios.

Chinese

志愿者的可靠性是许多非盈利组织的主要关注。为更加详细地解决这一问题,我们基于心理契约理论开发了志愿者可靠性理论模型。通过将本观点作为起点,我们检查了单个志愿者特点、组织因素和社会发展如何塑造志愿者和非盈利组织之间的诱因和贡献。我们讨论了这些因素如何导致心理契约的压力,同时确定了志愿者可靠行为的范围。为此,我们开发了理论框架来解决志愿者管理的可靠性问题。

Arabic

صلابة المتطوعين هي مصدر قلق كبير لكثير من المنظمات الغير ربحية. للحديث عن هذه المشكلة بمزيد من التفاصيل، نحن نضع نموذج نظري لصلابة المتطوعين على أساس نظرية العقد النفسي. من خلال أخذ هذا المنظور كنقطة إنطلاق، نستكشف كيف أن الخصائص الفردية للمتطوعين، العوامل التنظيمية، التطورات الإجتماعية تشكل تبادل الحوافز والمساهمات بين المتطوعين والمنظمات الغير ربحية. نناقش كيف يمكن لهذه العوامل أن تخلق التوترات في العقد النفسي وتحديد إلى أي مدى يتصرف المتطوعين بثقة. على هذا النحو، نضع إطار نظري للحديث عن مشكلة الجدارة في الثقة في إدارة المتطوعين.

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References

  • Anheier, H. K. (2014). Nonprofit organizations: Theory, management, policy (2nd ed.). New York, NY: Routledge.

    Google Scholar 

  • Anheier, H., & Salamon, L. (1999). Volunteering in cross-national perspective: Initial comparisons. Law and Contemporary Problems, 62(4), 43–65.

    Article  Google Scholar 

  • Bal, P. M., Chiaburu, D. S., & Diaz, I. (2011). Does psychological contract breach decrease proactive behaviors? The moderating effect of emotion regulation. Group and Organization Management, 36(6), 722–758.

    Article  Google Scholar 

  • Battilana, J., & Dorado, S. (2010). Building sustainable hybrid organizations: The case of commercial microfinance organizations. Academy of Management Journal, 53(6), 1419–1440.

    Article  Google Scholar 

  • Beckmann, N., Wood, R. E., & Minbashian, A. (2010). It depends how you look at it: On the relationship between neuroticism and conscientiousness at the within-and the between person levels of analysis. Journal of Research in Personality, 44(5), 593–601.

    Article  Google Scholar 

  • Bidee, J., Vantilborgh, T., Pepermans, R., Huybrechts, G., Willems, J., & Jegers, M. (2013). Autonomous motivation stimulates volunteers’ work effort: A self-determination theory approach to volunteerism. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 24(1), 32–47.

    Article  Google Scholar 

  • Blau, P. (1964). Exchange and power in social life. New York: Wiley.

    Google Scholar 

  • Boezeman, E. J., & Ellemers, N. (2008). Volunteer recruitment: The role of organizational support and anticipated respect in non-volunteers’ attraction to charitable volunteer organizations. The Journal of Applied Psychology, 93(5), 1013–1026.

    Article  Google Scholar 

  • Boezeman, E. J., & Ellemers, N. (2009). Intrinsic need satisfaction and the job attitudes of volunteers versus employees working in a charitable volunteer organization. Journal of Occupational and Organizational Psychology, 82(4), 897–914.

    Article  Google Scholar 

  • Borzaga, C., & Tortia, E. (2006). Worker motivations, job satisfaction, and loyalty in public and nonprofit social services. Nonprofit and Voluntary Sector Quarterly, 35(2), 225–248.

    Article  Google Scholar 

  • Bunderson, J. S., & Thompson, J. A. (2009). The call of the wild: Zookeepers, callings, and the double-edged sword of deeply meaningful work. Administrative Science Quarterly, 54(1), 32–57.

    Article  Google Scholar 

  • Chao, J. M. C., Cheung, F. Y. L., & Wu, A. M. S. (2011). Psychological contract breach and counterproductive workplace behaviors: Testing moderating effect of attribution style and power distance. The International Journal of Human Resource Management, 22(4), 763–777.

    Article  Google Scholar 

  • Clary, E. G. G., & Snyder, M. (1999). The motivations to volunteer: Theoretical and practical considerations. Current Directions in Psychological Science, 8(5), 156–159.

    Article  Google Scholar 

  • Clary, E. G., Snyder, M., Ridge, R. D., Copeland, J., Stukas, A. A., Haugen, J., et al. (1998). Understanding and assessing the motivations of volunteers: A functional approach. Journal of Personality and Social Psychology, 74(6), 1516–1530.

    Article  Google Scholar 

  • Cnaan, R., & Cascio, T. (1998). Performance and commitment: Issues in management of volunteers in human service organizations. Journal of Social Service Research, 24(3), 1–37.

    Article  Google Scholar 

  • Conway, N., & Briner, R. B. (2009). Fifty years of psychological contract research: What do we know and what are the main challenges? International Review of Industrial and Organizational Psychology, 21, 71–131.

    Google Scholar 

  • Corporation for National and Community Service (2017). Volunteering and civic life in America. Retrieved from http://www.nationalservice.gov/vcla/national.

  • Coyle-Shapiro, J., & Kessler, I. (2002). Exploring reciprocity through the lens of the psychological contract: Employee and employer perspectives. European Journal of Work and Organizational Psychology, 11(1), 69–86.

    Article  Google Scholar 

  • Cuskelly, G., Auld, C., Harrington, M., & Coleman, D. (2004). Predicting the behavioral dependability of sport event volunteers. Event Management, 9(1–2), 73–89.

    Article  Google Scholar 

  • Dart, R. (2004). The legitimacy of social enterprise. Nonprofit Management and Leadership, 14(4), 411–424.

    Article  Google Scholar 

  • De Cuyper, N., Rigotti, T., Witte, H. De, & Mohr, G. (2008). Balancing psychological contracts: Validation of a typology. The International Journal of Human Resource Management, 19(4), 543–561.

    Article  Google Scholar 

  • De Jong, J., Schalk, R., & De Cuyper, N. (2009). Balanced versus unbalanced psychological contracts in temporary and permanent employment: Associations with employee attitudes. Management and Organization Review, 5(3), 329–351.

    Article  Google Scholar 

  • Eckstein, S. (2001). Community as gift-giving: Collectivistic roots of volunteerism. American Sociological Review, 66(6), 829–851.

    Article  Google Scholar 

  • Eikenberry, A., & Kluver, J. (2004). The marketization of the nonprofit sector: Civil society at risk? Public Administration Review, 64(2), 132–140.

    Article  Google Scholar 

  • Elshaug, C., & Metzer, J. (2001). Personality attributes of volunteers and paid workers engaged in similar occupational tasks. The Journal of Social Psychology, 141(6), 752–763.

    Article  Google Scholar 

  • Farmer, S. M., & Fedor, D. B. (1999). Volunteer participation and withdrawal. Nonprofit Management and Leadership, 9(4), 349–368.

    Article  Google Scholar 

  • Finkelstein, M., Penner, L., & Brannick, M. T. (2005). Motive, role identity, and prosocial personality as predictors of volunteer activity. Social Behavior and Personality, 33(4), 403–418.

    Article  Google Scholar 

  • Gouldner, A. W. (1960). The norm of reciprocity: A preliminary statement. American Sociological Review, 25(2), 161–178.

    Article  Google Scholar 

  • Griep, Y., Vantilborgh, T., Baillien, E., & Pepermans, R. (2016). The mitigating role of leader-member exchange when perceiving psychological contract violation: A diary survey study among volunteers. European Journal of Work and Organizational Psychology, 25(2), 254–271.

    Article  Google Scholar 

  • Haivas, S., Hofmans, J., & Pepermans, R. (2014). “What motivates you doesn’t motivate me”: Individual differences in the needs satisfaction–motivation relationship of Romanian volunteers. Applied Psychology, 63(2), 326–343.

    Article  Google Scholar 

  • Holmstrom, B., & Milgrom, P. (1991). Multitask principal-agent analyses: Incentive contracts, asset ownership, and job design. Journal of Law Economics and Organization, 7, 24–52.

    Article  Google Scholar 

  • House, R. J., & Rizzo, J. R. (1972). Role conflict and ambiguity as critical variables in a model of organizational behavior. Organizational Behavior and Human Performance, 7, 467–505.

    Article  Google Scholar 

  • Hustinx, L., & Lammertyn, F. (2003). Collective and reflexive styles of volunteering: A sociological modernization perspective. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 14(2), 167–187.

    Article  Google Scholar 

  • Hwang, H., & Powell, W. (2009). The rationalization of charity: The influences of professionalism in the nonprofit sector. Administrative Science Quarterly, 54(2), 268–298.

    Article  Google Scholar 

  • Jay, J. (2013). Navigating paradox as a mechanism of change and innovation in hybrid organizations. Academy of Management Journal, 56(1), 137–159.

    Article  Google Scholar 

  • Jensen, M. C., & Meckling, W. H. (1976). Theory of the firm: Managerial behavior, agency costs and ownership structure. Journal of Financial Economics, 3, 305–360.

    Article  Google Scholar 

  • Jensen, J., Opland, R., & Ryan, A. (2009). Psychological contracts and counterproductive work behaviors: Employee responses to transactional and relational breach. Journal of Business and Psychology, 25(4), 555–568.

    Article  Google Scholar 

  • Johns, G. (2010). Presenteeism in the workplace: A review and research agenda. Journal of Organizational Behavior, 31(4), 519–542.

    Article  Google Scholar 

  • Judge, T. A., & Piccolo, R. F. (2004). Transformational and transactional leadership: A meta-analytic test of their relative validity. Journal of Applied Psychology, 89(5), 755–768.

    Article  Google Scholar 

  • Kreutzer, K., & Jager, U. (2011). Volunteering versus managerialism: Conflict over organizational identity in voluntary associations. Nonprofit and Voluntary Sector Quarterly, 40(4), 634–661.

    Article  Google Scholar 

  • Kristof-Brown, A. L., Zimmerman, R. D., & Johnson, E. C. (2005). Consequences of individuals’ fit at work: A meta-analysis of person-job, person-organization, person-group, and person-supervisor fit. Personnel Psychology, 58, 281–342.

    Article  Google Scholar 

  • Lambert, L. (2011). Promised and delivered inducements and contributions: An integrated view of psychological contract appraisal. Journal of Applied Psychology, 96(4), 695–712.

    Article  Google Scholar 

  • Liao-Troth, M. A. (2001). Attitude differences between paid workers and volunteers. Nonprofit Management and Leadership, 11(4), 423–442.

    Article  Google Scholar 

  • Liao-Troth, M. A. (2005). Are they here for the long haul? The effects of functional motives and personality factors on the psychological contracts of volunteers. Nonprofit and Voluntary Sector Quarterly, 34(4), 510–530.

    Article  Google Scholar 

  • Machin, J., & Paine, A. E. (2008). Management matters: A national survey of volunteer management capacity. London: Institute for Volunteering Research.

    Google Scholar 

  • Maier, F., Meyer, M., & Steinbereithner, M. (2016). Nonprofit organizations becoming business-like a systematic Review. Nonprofit and Voluntary Sector Quarterly, 45(1), 64–86.

    Article  Google Scholar 

  • McCrae, R. R., & John, O. P. (1992). An introduction to the five-factor model and its applications. Journal of Personality, 60(2), 175–215.

    Article  Google Scholar 

  • Meijs, L., & Brudney, J. (2007). Winning volunteer scenarios: The soul of a new machine. International Journal of Volunteer Administration, XXIV(6), 68–79.

    Google Scholar 

  • Montagna, P. D. (1968). Professionalization and bureaucratization in large professional organizations. American Journal of Sociology, 74(2), 138–145.

    Article  Google Scholar 

  • Morrison, E., & Robinson, S. (1997). When employees feel betrayed: A model of how psychological contract violation develops. Academy of Management Review, 22(1), 226–256.

    Google Scholar 

  • Nichols, G. (2013). The psychological contract of volunteers: A new research agenda. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 24(4), 986–1005.

    Article  Google Scholar 

  • Nichols, G., & Ojala, E. (2009). Understanding the management of sports events volunteers through psychological contract theory. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 20(4), 369–387.

    Article  Google Scholar 

  • Pache, A., & Insead, F. (2013). Inside the hybrid organization: Selective coupling as a response to competing institutional logics. Academy of Management Journal, 56(4), 972–1001.

    Article  Google Scholar 

  • Pearce, J. (1993). Volunteers: The organizational behavior of unpaid workers. London: Routledge.

    Google Scholar 

  • Raja, U., Johns, G., & Ntalianis, F. (2004). The impact of personality on psychological contracts. Academy of Management Journal, 47(3), 350–367.

    Article  Google Scholar 

  • Restubog, S. L. D., Bordia, P., & Tang, R. L. (2006). Effects of psychological contract breach on performance of IT employees: The mediating role of affective commitment. Journal of Occupational and Organizational Psychology, 79(2), 299–306.

    Article  Google Scholar 

  • Rousseau, D. (1989). Psychological and implied contracts in organizations. Employee Responsibilities and Rights Journal, 2(2), 121–139.

    Article  Google Scholar 

  • Rousseau, D. (1990). New hire perceptions of their own and their employer’s obligations: A study of psychological contracts. Journal of Organizational Behavior, 11(5), 389–400.

    Article  Google Scholar 

  • Rousseau, D. (1995). Psychological contracts in organizations: Understanding written and unwritten agreements. Thousand Oaks: SAGE Publications.

    Google Scholar 

  • Ryan, W. (2002). The new landscape for nonprofits. In V. Futter, J. Cion, & G. Overton (Eds.), Nonprofit governance and management (pp. 13–28). Chicago: American Bar Association.

    Google Scholar 

  • Sanders, M. L., & McClellan, J. G. (2014). Being business-like while pursuing a social mission: Acknowledging the inherent tensions in US nonprofit organizing. Organization, 21(1), 68–89.

    Article  Google Scholar 

  • Solinger, O. N., van Olffen, W., Roe, R. A., & Hofmans, J. (2013). On becoming (un) committed: A taxonomy and test of newcomer onboarding scenarios. Organization Science, 24(6), 1640–1661.

    Article  Google Scholar 

  • Speckbacher, G. (2013). The use of incentives in nonprofit organizations. Nonprofit and Voluntary Sector Quarterly, 42(5), 1006–1025.

    Article  Google Scholar 

  • Studer, S., & von Schnurbein, G. (2013). Organizational factors affecting volunteers: A literature review on volunteer coordination. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 24(2), 403–440.

    Article  Google Scholar 

  • Suazo, M. M., Martínez, P. G., & Sandoval, R. (2009). Creating psychological and legal contracts through human resource practices: A signaling theory perspective. Human Resource Management Review, 19(2), 154–166.

    Article  Google Scholar 

  • Tekleab, A. G., & Taylor, M. S. (2003). Aren’t there two parties in an employment relationship? Antecedents and consequences of organization-employee agreement on contract obligations and violations. Journal of Organizational Behavior, 24(5), 585–608.

    Article  Google Scholar 

  • Thomas, D. C., Fitzsimmons, S. R., Ravlin, E. C., Au, K. Y., Ekelund, B. Z., & Barzantny, C. (2010). Psychological contracts across cultures. Organization Studies, 31(11), 1437–1458.

    Article  Google Scholar 

  • Thompson, J. A., & Bunderson, J. S. (2003). Violations of principle: Ideological currency in the psychological contract. Academy of Management Review, 28(4), 571–586.

    Google Scholar 

  • Tomprou, M., Rousseau, D. M., & Hansen, S. D. (2015). The psychological contracts of violation victims: A post-violation model. Journal of Organizational Behavior, 36(4), 561–581.

    Article  Google Scholar 

  • Tsui, A. S., Pearce, J. L., Porter, L. W., & Tripoli, A. M. (1997). Alternative approaches to the employee-organization relationship: Does investment in employees pay off? Academy of Management Journal, 40(5), 1089–1121.

    Article  Google Scholar 

  • Van Puyvelde, S. (2016). Nonprofit organization governance: A theoretical review. Leiden: Brill.

    Google Scholar 

  • Van Puyvelde, S., Caers, R., Du Bois, C., & Jegers, M. (2012). The governance of nonprofit organizations: Integrating agency theory with stakeholder and stewardship theories. Nonprofit and Voluntary Sector Quarterly, 41(3), 431–451.

    Article  Google Scholar 

  • Van Puyvelde, S., Caers, R., Du Bois, C., & Jegers, M. (2013). Agency problems between managers and employees in nonprofit organizations: A discrete choice experiment. Nonprofit Management and Leadership, 24(1), 63–85.

    Article  Google Scholar 

  • van Vuuren, M., de Jong, M., & Seydel, E. (2008). Commitment with or without a stick of paid work: Comparison of paid and unpaid workers in a nonprofit organization. European Journal of Work and Organizational Psychology, 17(3), 315–326.

    Article  Google Scholar 

  • Vantilborgh, T. (2015). Volunteers’ reactions to psychological contract fulfillment in terms of exit, voice, loyalty, and neglect behavior. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 26(2), 604–628.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Griep, Y., & Hofmans, J. (2016). Antecedents of psychological contract breach: The role of job demands, job resources, and affect. PLoS ONE, 11(5), e0154696.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Willems, J., Huybrechts, G., & Jegers, M. (2011). A new deal for NPO governance and management: Implications for volunteers using psychological contract theory. VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations, 22(4), 639–657.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Willems, J., Huybrechts, G., & Jegers, M. (2012). Volunteers’ psychological contracts: Extending traditional views. Nonprofit and Voluntary Sector Quarterly, 41(6), 1072–1091.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Willems, J., Huybrechts, G., & Jegers, M. (2013a). From “getting” to “giving”: Exploring age-related differences in perceptions of and reactions to psychological contract balance. European Journal of Work and Organizational Psychology, 22(3), 293–305.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Willems, J., Huybrechts, G., & Jegers, M. (2013b). Revisiting the relationship between personality and psychological contracts: A moderated mediation model explaining volunteer performance. Social Service Review, 87(1), 158–186.

    Article  Google Scholar 

  • Vantilborgh, T., Bidee, J., Pepermans, R., Willems, J., Huybrechts, G., & Jegers, M. (2014). Effects of ideological and relational psychological contract breach and fulfilment on volunteers’ work effort. European Journal of Work and Organizational Psychology, 23(2), 217–230.

    Article  Google Scholar 

  • Weisbrod, B. A. (1998). To profit or not to profit: The commercial transformation of the nonprofit sector. Cambridge: Cambridge University Press.

    Book  Google Scholar 

  • Willems, J., Huybrechts, G., Jegers, M., Vantilborgh, T., Bidee, J., & Pepermans, R. (2012). Volunteer decisions (not) to leave: Reasons to quit versus functional motives to stay. Human Relations, 65(7), 883–900.

    Article  Google Scholar 

  • Zhao, H., Wayne, S. J., Glibkowski, B. C., & Bravo, J. (2007). The impact of psychological contract breach on work-related outcomes: A meta-analysis. Personnel Psychology, 60(3), 647–680.

    Article  Google Scholar 

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Acknowledgements

An earlier version of this paper was presented at the 10th Workshop on the Challenges of Managing the Third Sector, European Institute for Advanced Studies in Management (EIASM), Edinburgh, United Kingdom, June 11–12, 2015. We would like to thank the participants for their helpful comments.

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  1. Department of Work and Organizational Psychology, Free University of Brussels, Pleinlaan 2, 1050, Brussels, Belgium

    Tim Vantilborgh

  2. Department of Applied Economics, Free University of Brussels, Pleinlaan 2, 1050, Brussels, Belgium

    Stijn Van Puyvelde

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  1. Tim Vantilborgh
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Vantilborgh, T., Van Puyvelde, S. Volunteer Reliability in Nonprofit Organizations: A Theoretical Model. Voluntas 29, 29–42 (2018). https://doi.org/10.1007/s11266-017-9909-2

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