Main Article Content
Abstract
Referral reward programs have become a central and cost-effective strategy for customer acquisition in digital marketing. This study examines the direct and interactive effects of reward type (monetary vs. nonmonetary) and task complexity (low vs. high) on customer engagement in referral reward programs. Using real-world engagement data, we analyze 541 referral program posts from 13 brands. Applying Multivariate Analysis of Covariance (MANCOVA), the results indicate that nonmonetary rewards consistently elicit higher customer engagement than monetary rewards, while high task complexity significantly dampens engagement. Importantly, the findings uncover a meaningful interaction effect: when task complexity is low, monetary and nonmonetary rewards generate comparable levels of engagement; however, as task complexity increases, nonmonetary rewards become markedly more effective than monetary rewards in driving engagement. Through integrating reward design with task-related cost considerations, this study offers a more nuanced understanding of how referral reward programs influence customer engagement in digital environments. The study advances the referral marketing literature by providing empirical evidence from real in-market social media campaigns and by identifying task complexity as a critical boundary condition that shapes the effectiveness of reward types. Overall, the findings underscore the strategic importance of aligning reward types with task demands to enhance engagement outcomes and strengthen consumer–brand relationships in competitive digital markets.
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References
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References
Bagozzi, R. P. (1975). Exchange in Marketing. Journal of the Academy of Marketing Science, 3(4), 314–327.
Beckers, S. F. M., Doorn, J. Van, & Verhoef, P. C. (2017). Good, better, engaged? The effect of company-initiated customer engagement behavior on shareholder value. Journal of the Academy of Marketing Science, 46(3), 366–383. https://doi.org/10.1007/s11747-017-0539-4
Blau, P. M. (1964). Exchange and power in social life (1st ed.). New York.
Brodie, R. J., Ilic, A., Juric, B., & Hollebeek, L. (2013). Consumer engagement in a virtual brand community: An exploratory analysis. Journal of Business Research, 66(1), 105–114. https://doi.org/10.1016/j.jbusres.2011.07.029
Campbell J., D. (1988). Task Complexity Review and Analysis. Academy of Management Review, 13(1), 40–52.
Carrasco, F. (2021). "Kantar's Brand Footprint 2021", available at: https://www.kantarworldpanel.com/vn/news/Vietnam-most-chosen-brands-and-brand-owners-in-2021
Chen, H., & Hao, S. (2024). Dollar or percentage? The effect of reward presentation on referral likelihood. Asia Pacific Journal of Marketing and Logistics, 36(6), 1504–1519. https://doi.org/10.1108/APJML-07-2023-0678
Chen, R., Yuan, R., Huang, B., & Liu, M. J. (2023). Feeling warm or skeptical? An investigation into the effects of incentivized eWOM programs on customers' eWOM sharing intentions. Journal of Business Research, 167(4), 1–12. https://doi.org/10.1016/j.jbusres.2023.114178
De Vries, L., Gensler, S., & Leeflang, P. S. H. (2012). Popularity of Brand Posts on Brand Fan Pages: An Investigation of the Effects of Social Media Marketing. Journal of Interactive Marketing, 26(2), 83–91. https://doi.org/10.1016/j.intmar.2012.01.003
Drossos, D., Coursaris, C., & Kagiouli, E. (2024). Social media marketing content strategy: A comprehensive framework and empirically supported guidelines for brand posts on Facebook pages. Journal of Consumer Behaviour, 23(3), 1175–1192. https://doi.org/10.1002/cb.2269
Duh, R. R., Kuo, L. C., & Yan, J. C. (2018). The effects of review form and task complexity on auditor performance. Asia Pacific Journal of Accounting and Economics, 25(3), 449–462. https://doi.org/10.1080/16081625.2017.1346479
Errmann, A., Seo, Y., Choi, Y. K., & Yoon, S. (2019). Divergent Effects of Friend Recommendations on Disclosed Social Media Advertising in the United States and Korea. Journal of Advertising, 48(5), 495–511. https://doi.org/10.1080/00913367.2019.1663320
Fu, X., & Pang, J. (2018). Effect of e-referral incentive programs on referrer loyalty on social platforms. Service Industries Journal, 42(15), 1234–1255. https://doi.org/10.1080/02642069.2018.1505872
Gershon, R., Cryder, C., & John, L. K. (2020). Why Prosocial Referral Incentives Work: The Interplay of Reputational Benefits and Action Costs. Journal of Marketing Research, 57(1), 156–172. https://doi.org/10.1177/0022243719888440
Gu, W., Chan, K. W., Kwon, J., Dhaoui, C., & Septianto, F. (2023). Informational vs. emotional B2B firm-generated content on social media engagement: Computerized visual and textual content analysis. Industrial Marketing Management, 112(1), 98–112. https://doi.org/10.1016/j.indmarman.2023.04.012
Ha, J. (2022). Vietnam's FMCG market. Retrieved from https://www.kantarworldpanel.com/vn/news/FMCG-Monitor-Q3-the-recovery-of-beverage-sector-in-VN
Hair, J. F., Anderson, R. E., Tatham, R. L., & Black, W. C. (2019). Multivariate Data Analysis (8th ed.). Cengage.
Harmeling, C. M., Moffett, J. W., Arnold, M. J., & Carlson, B. D. (2017). Toward a theory of customer engagement marketing. Journal of the Academy of Marketing Science, 45(3), 312–335. https://doi.org/10.1007/s11747-016-0509-2
Hollebeek, L. D., Glynn, M. S., & Brodie, R. J. (2014). Consumer brand engagement in social media: Conceptualization, scale development, and validation. Journal of Interactive Marketing, 28(2), 149–165. https://doi.org/10.1016/j.intmar.2013.12.002
Hughes, C., Swaminathan, V., & Brooks, G. (2019). Driving Brand Engagement Through Online Social Influencers: An Empirical Investigation of Sponsored Blogging Campaigns. Journal of Marketing, 83(5), 78–96. https://doi.org/10.1177/0022242919854374
Jiang, F., Zhu, S., & Zhang, Y. (2024). Impact of altruism-preference differences on the optimal reward structure in online referral marketing. Managerial and Decision Economics, 45(1), 247–263.
Jiang, Z., & Benbasat, I. (2007). The effects of presentation formats and task complexity on online consumers' product understanding. MIS Quarterly: Management Information Systems, 31(3), 475–500. https://doi.org/10.2307/25148804
Jin, H., Lu, S., & Wang, K. (2024). Who is more likely to initiate referrals? Effect of consumers' regulatory focus on referral intention. Journal of Retailing and Consumer Services, 77(7), 1–13. https://doi.org/10.1016/j.jretconser.2023.103650
Jin, L., & Huang, Y. (2014). When giving money does not work: The differential effects of monetary versus in-kind rewards in referral reward programs. International Journal of Research in Marketing, 31(1), 107–116. https://doi.org/10.1016/j.ijresmar.2013.08.005
Jung, J., Bapna, R., Golden, J., & Sun, T. (2020). Words Matter! Towards Pro-Social Call-to-Action for Online Referral: Evidence from Two Field Experiments. Information System Research, 31(1), 16–36. https://doi.org/10.2139/ssrn.3177845
Krowinska, A., & Dineva, D. (2025). The role and forms of social media branded content are driving active customer engagement behaviours. Journal of Marketing Management, 41(9), 1030–1060. https://doi.org/10.1080/0267257X.2025.2544808
Kuang, D., Li, X. F., & Bi, W. W. (2021). How to effectively design referral rewards to increase the referral likelihood for green products. Sustainability, 13(13), 1–16. https://doi.org/10.3390/su13137177
Kumar, V., & Pansari, A. (2016). Competitive advantage through engagement. Journal of Marketing Research, 53(4), 497–514. https://doi.org/10.1509/jmr.15.0044
Kumar, V., Petersen, J. A., & Leone, R. P. (2010). Driving profitability by encouraging customer referrals: Who, when, and how. Journal of Marketing, 74(5), 1–17. https://doi.org/10.1509/jmkg.74.5.1
Leech, N. L. (2016). IBM SPSS for Intermediate Statistics (5th ed.). New York.
Li, Y., & Xie, Y. (2020). Is a Picture Worth a Thousand Words? An Empirical Study of Image Content and Social Media Engagement. Journal of Marketing Research, 57(1), 1–19. https://doi.org/10.1177/0022243719881113
Liu, P., & Li, Z. (2012). Task complexity: A review and conceptualization framework. International Journal of Industrial Ergonomics, 42(6), 553–568. https://doi.org/10.1016/j.ergon.2012.09.001
Ma, S., Xie, Q., Wang, J., & Dong, J. (2024). The effect of referral tasks on customers' referral likelihood on social platforms. Nankai Business Review International, 15(4), 595–618. https://doi.org/10.1108/NBRI-03-2023-0027
Ndruru, F., Cahyono, B. Y., Rovikasari, M., & Mulati, D. F. (2025). Unpacking the impact of writing task complexity, use of digital tools, and engagement strategies on university students' academic writing performance. Journal of Information Technology Education: Research, 24(1), 1–23. https://doi.org/10.28945/5609
Pansari, A., & Kumar, V. (2017). Customer engagement: the construct, antecedents, and consequences. Journal of the Academy of Marketing Science, 45(3), 294–311. https://doi.org/10.1007/s11747-016-0485-6
Peng, X., Xing, Y., Tian, Y., Fei, M., & Wang, Q. (2023). Nonmonetary rewards of referral reward programs and recommendation intention: The role of reward–product congruity. Decision Support Systems, 173(2), 1–13. https://doi.org/10.1016/j.dss.2023.113999
Ryu, G. & Feick, L. (2007). A penny for your thoughts: Referral reward programs and referral likelihood. Journal of Marketing, 71(1), 84–94. https://doi.org/10.1509/jmkg.71.1.84
Purba, G. A., & Mansyur, A. (2025). The moderating role of organizational support in the relationships among problem-solving, task complexity, and work engagement. Journal of Management: Small and Medium Enterprises (SMEs), 18(3), 2017-2030. https://doi.org/10.35508/jom.v18i3.22343
Sabate, F., Berbegal-Mirabent, J., Cañabate, A., & Lebherz, P. R. (2014). Factors influencing the popularity of branded content in Facebook fan pages. European Management Journal, 32(6), 1001–1011. https://doi.org/10.1016/j.emj.2014.05.001
Safitri, D., & Komaryatin, N. (2025). Digital Marketing Influence on Marketing Performance: The Role of Customer Engagement and Relationship Marketing. Golden Ratio of Marketing and Applied Psychology of Business, 5(2), 316–331. https://doi.org/10.52970/grmapb.v5i2.960
Santoso, G. M., & Agustini, M. Y. D. H. (2026). Customer Engagement Levels: Analysis of Behaviour, Emotional, and Cognitive Dimensions. Golden Ratio of Marketing and Applied Psychology of Business, 6(1), 98–106. https://doi.org/10.52970/grmapb.v6i1.1286
Schwehm, K., & Prigge, J. K. (2022, May). Give It Away and Get It Back? on the Role and Nature of Giveaway Campaigns by Social Media Influencers, Paper presented at the 13th European Conference on Information Systems, Timisoara, Romania.
Simon, K. (2022). "Digital 2022: Vietnam, available at: https://datareportal.com/reports/digital-2022-vietnam
Shahbaznezhad, H., Dolan, R., & Rashidirad, M. (2021). The Role of Social Media Content Format and Platform in Users' Engagement Behavior. Journal of Interactive Marketing, 53(1), 47–65. https://doi.org/10.1016/j.intmar.2020.05.001
Sun, T., Viswanathan, S., & Zheleva, E. (2020). Creating Social Contagion Through Firm-Mediated Message Design: Evidence from a Randomized Field Experiment. Management Science, 67(2), 1–20.
Swani, K., Milne, G., & Brown, B. P. (2013). Spreading the word through likes on Facebook: Evaluating the message strategy effectiveness of Fortune 500 companies. Journal of Research in Interactive Marketing, 7(4), 269–294. https://doi.org/10.1108/JRIM-05-2013-0026
Tellis, G. J., MacInnis, D. J., Tirunillai, S., & Zhang, Y. (2019). What Drives Virality of Online Digital Content? The Critical Role of Information, Emotion, and Brand Prominence. Journal of Marketing, 83(4), 1–20. https://doi.org/10.1177/0022242919841034
Van Den Bulte, C., Bayer, E., Skiera, B., & Schmitt, P. (2018). How customer referral programs turn social capital into economic capital. Journal of Marketing Research, 55(1), 132–146. https://doi.org/10.1509/jmr.14.0653
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