電子商務在新冠疫情的影響下快速崛起，企業紛紛尋求新興的行銷模式以因應數位時代的來臨。在此背景下，運用KOL作為產品和品牌的代言人，已逐漸成為備受企業青睞且廣泛採用的行銷策略。有鑑於KOL行銷手法的日趨普及，本研究旨在分析KOL與產品間的一致性、KOL特質對其來源可信度的影響，以及廣告頻率對廣告效果與購買意願的調節作用。
本研究最終共收回330份問卷，並發現，KOL與產品之間的一致性會正向影響KOL的來源可信度評價；KOL具備較高來源可信度將有助於增進廣告效果；並且廣告頻率在調節廣告效果與購買意願的過程中，相較於廣告態度，對品牌態度有較大的調節作用，根據研究實證結果，針對未來選擇KOL作為產品及品牌行銷策略時，提出相關的管理意涵與建議。

The swift growth of e-commerce driven by the COVID-19 pandemic has forced businesses to develop innovative marketing strategies to keep pace with the digital age. Against this backdrop, employing Key Opinion Leaders (KOLs) as product and brand endorsers has gradually become a favored marketing strategy among enterprises. Given the increasing prevalence of KOL marketing, this study aims to investigate the congruence between products and KOLs, as well as the influence of KOL characteristics on their source credibility, and the moderating role of advertising frequency on advertising effectiveness and purchase intention.
For this study, 330 questionnaires were collected in total. The results suggest that when there is congruence between KOLs and the products they promote, it positively impacts the perceived credibility of the KOL as a source. KOLs with higher source credibility contribute to enhanced advertising effectiveness. Furthermore, in the process of moderating advertising effectiveness and purchase intention, advertising frequency has a greater impact on brand attitude compared to advertising attitude. Drawing for the empirical findings, this study offers managerial implications and recommendations for the selection of KOLs in future product and brand marketing strategies.

中文文獻
Meta (2020年11月19日)。後疫情時代，善用社群平台創造全通路策略的世代已加速來臨。Facebook Business。https://www.facebook.com/business/news/micro-shifts-insights-for-retail-in-taiwan/#
曹幀柅 (2022年1月22日)。後疫情時代社群電商引領網購新趨勢。電子商務時報。https://www.ectimes.org.tw/2022/01/%E3%80%90%E5%B0%88%E9%A1%8C%E5%A0%B1%E5%B0%8E%E3%80%91%E5%BE%8C%E7%96%AB%E6%83%85%E6%99%82%E4%BB%A3%E3%80%80%E7%A4%BE%E7%BE%A4%E9%9B%BB%E5%95%86%E5%BC%95%E9%A0%98%E7%B6%B2%E8%B3%BC%E6%96%B0%E8%B6%A8/
彭賢恩、石安伶、謝宜儒、陳韋辰。 (2021年6月)。第三級警戒下防疫新生活調查：生活篇。台灣趨勢研究。https://www.twtrend.com/trend-detail/COVID-19-Level3-new-life-survey01/

英文文獻
Amos, C., Holmes, G., & Strutton, D. (2008). Exploring the relationship between celebrity endorser effects and advertising effectiveness: A quantitative synthesis of effect size. International journal of advertising, 27(2), 209-234.
Baker, M. J., & Churchill Jr, G. A. (1977). The impact of physically attractive models on advertising evaluations. Journal of Marketing research, 14(4), 538-555.
Biswas, D., Biswas, A., & Das, N. (2006). The differential effects of celebrity and expert endorsements on consumer risk perceptions: The role of consumer knowledge, perceived congruency, and product technology orientation. Journal of advertising, 17-31.
Breves, P. L., Liebers, N., Abt, M., & Kunze, A. (2019). The perceived fit between instagram influencers and the endorsed brand: How influencer–brand fit affects source credibility and persuasive effectiveness. Journal of Advertising Research, 59(4), 440-454.
Burton, S., Lichtenstein, D. R., Netemeyer, R. G., & Garretson, J. A. (1998). A scale for measuring attitude toward private label products and an examination of its psychological and behavioral correlates. Journal of the academy of marketing science, 26, 293-306.
Cacioppo, J. T., & Petty, R. E. (1989). Effects of message repetition on argument processing, recall, and persuasion. Basic and applied social psychology, 10(1), 3-12.
Casaló, L. V., Flavián, C., & Ibáñez-Sánchez, S. (2020). Influencers on Instagram: Antecedents and consequences of opinion leadership. Journal of Business Research, 117, 510-519.
Chiou, Y. H., Chen, M. H., Huang, L. S., Huang, L. R., & Hu, S. R. (2008). The effects of blog product placement type and source credibility on the attitudes toward product placement in Taiwan. In International Conference on Business and Information (BAI2008).
Dodds, W. B., Monroe, K. B., & Grewal, D. (1991). Effects of price, brand, and store information on buyers’ product evaluations. Journal of Marketing Research, 28(3), 307-319.
Dwivedi, A., & Johnson, L. W. (2013). Trust–commitment as a mediator of the celebrity endorser–brand equity relationship in a service context. Australasian Marketing Journal, 21(1), 36-42.
Goldsmith, R. E., Lafferty, B. A., & Newell, S. J. (2000). The impact of corporate credibility and celebrity credibility on consumer reaction to advertisements and brands. Journal of Advertising, 43-54.
Gong, W., & Li, X. (2017). Engaging fans on microblog: the synthetic influence of parasocial interaction and source characteristics on celebrity endorsement. Psychology & Marketing, 34(7), 720-732.
Ha, N. M., & Lam, N. H. (2017). The effects of celebrity endorsement on customer’s attitude toward brand and purchase intention. International Journal of Economics and Finance, 9(1), 64-77.
He, W., & Jin, C. (2022). A study on the influence of the characteristics of key opinion leaders on consumers’ purchase intention in live streaming commerce: based on dual-systems theory. Electronic Commerce Research, 1-31.
Heckler, S. E., & Childers, T. L. (1992). The role of expectancy and relevancy in memory for verbal and visual information: what is incongruency? Journal of Consumer Research, 18(4), 475-492.
Herrington, J. D., & Henley Jr, J. A. (2000). Comparing the relative impact of services and non-services advertising: The case of insurance vs. automobiles. Journal of promotion management, 5(2), 101-118.
Hovland, C. I., Janis, I. L., & Kelley, H. H. (1953). Communication and persuasion. New Haven, CT: Yale University Press
Jin, S. A. A., & Phua, J. (2014). Following celebrities’ tweets about brands: The impact of twitter-based electronic word-of-mouth on consumers’ source credibility perception, buying intention, and social identification with celebrities. Journal of advertising, 43(2), 181-195.
Kahle, L. R., & Homer, P. M. (1985). Physical attractiveness of the celebrity endorser: A social adaptation perspective. Journal of Consumer Research, 11(4), 954-961.
Kamins, M. A. (1990). An investigation into the" match-up" hypothesis in celebrity advertising: When beauty may be only skin deep. Journal of Advertising, 4-13.
Kamins, M. A., & Gupta, K. (1994). Congruence between spokesperson and product type: A matchup hypothesis perspective. Psychology & Marketing, 11(6), 569-586.
Katz, E. (1957). The two-step flow of communication: An up-to-date report on an hypothesis. Public Opinion Quarterly, 21(1), 61-78.
Keller, K. L. (1993). Conceptualizing, measuring, and managing customer-based brand equity. Journal of marketing, 57(1), 1-22.
Kim, D. Y., & Kim, H. Y. (2021). Influencer advertising on social media: The multiple inference model on influencer-product congruence and sponsorship disclosure. Journal of business research, 130, 405-415.
Kotler, P., & Keller, K. L. (2016). Marketing Management (15th global ed.). England: Pearson, 803-829.
Kotler, P., Keller, K. L., Ang, S. H., Tan, C. T., & Leong, S. M. (2018). Marketing Management: An Asian Perspective. London: Pearson.
Lee, Y., & Koo, J. (2015). Athlete endorsement, attitudes, and purchase intention: The interaction effect between athlete endorser-product congruence and endorser credibility. Journal of Sport Management, 29(5), 523-538.
Lou, C., & Yuan, S. (2019). Influencer marketing: How message value and credibility affect consumer trust of branded content on social media. Journal of Interactive Advertising, 19(1), 58-73.
Lueck, J. A. (2015). Friend-zone with benefits: The parasocial advertising of Kim Kardashian. Journal of Marketing Communications, 21(2), 91-109.
Lutz, R. J. (1985). Affective and cognitive antecedents of attitude toward the ad: A conceptual framework. Psychological Processes and Advertising Effects(pp. 45-64).
MacKenzie, S. B., Lutz, R. J., & Belch, G. E. (1986). The role of attitude toward the ad as a mediator of advertising effectiveness: A test of competing explanations. Journal of Marketing Research, 23(2), 130-143.
McCormick, K. (2016). Redefining the celebrity :‘self-made’versus ‘manufactured’celebrity endorsers’ impact on consumers’ attitudes and purchase intentions. Fashion, Style & Popular Culture, 3(3), 339-356.
McCracken, G. (1989). Who is the celebrity endorser? Cultural foundations of the endorsement process. Journal of Consumer Research, 16(3), 310-321.
McGuire, W. J. (1985). Attitudes and Attitude Change. Handbook of Social Psychology: Special Fields and Applications, (Vol. 2, pp. 233–346).
Mehta, A. (2000). Advertising attitudes and advertising effectiveness. Journal of Advertising Research, 40(3), 67-72.
Ohanian, R. (1990). Construction and validation of a scale to measure celebrity endorsers' perceived expertise, trustworthiness, and attractiveness. Journal of Advertising, 39-52.
Park, C. W., & Lessig, V. P. (1977). Students and housewives: Differences in susceptibility to reference group influence. Journal of Consumer Research, 4(2), 102-110.
Park, H. J., & Lin, L. M. (2020). The effects of match-ups on the consumer attitudes toward internet celebrities and their live streaming contents in the context of product endorsement. Journal of Retailing and Consumer services, 52, 101934.
Peters, R. G., & Bijmolt, T. H. (1997). Consumer memory for television advertising: A field study of duration, serial position, and competition effects. Journal of Consumer Research, 23(4), 362-372.
Schiffman, L. G., Kanuk, L. L. (2007) Consumer Behavior. Upper Saddle River, NJ: Pearson Prentice-Hall.
Schlosser, A. E., Shavitt, S., & Kanfer, A. (1999). Survey of Internet users' attitudes toward Internet advertising. Journal of Interactive Marketing, 13(3), 34-54.
Schmidt, S., & Eisend, M. (2015). Advertising repetition: A meta-analysis on effective frequency in advertising. Journal of Advertising, 44(4), 415-428.
Schouten, A. P., Janssen, L., & Verspaget, M. (2021). Celebrity vs. Influencer endorsements in advertising: the role of identification, credibility, and Product-Endorser fit. In Leveraged marketing communications (pp. 208-231). Routledge.
Spears, N., & Singh, S. N. (2004). Measuring attitude toward the brand and purchase intentions. Journal of Current Issues & Research in Advertising, 26(2), 53-66.
Tangari, A. H., Banerjee, S., & Verma, S. (2019). Making a good thing even better? The impact of claim congruency on competing product goals and consumer evaluations. Journal of Business Research, 101, 12-22.
Tellis, G. J. (2004). Effective advertising: Understanding when, how, and why advertising works. Thousand Oaks, CA: Sage.
Till, B. D., & Busler, M. (2000). The match-up hypothesis: Physical attractiveness, expertise, and the role of fit on brand attitude, purchase intent and brand beliefs. Journal of Advertising, 1-13.
Weismueller, J., Harrigan, P., Wang, S., & Soutar, G. N. (2020). Influencer endorsements: How advertising disclosure and source credibility affect consumer purchase intention on social media. Australasian Marketing Journal, 28(4), 160-170.
Zhou, Z., Zhang, Q., Su, C., & Zhou, N. (2012). How do brand communities generate brand relationships? Intermediate mechanisms. Journal of Business Research, 65(7), 890-895.
Zou, Y., & Peng, F. (2019, June). Key opinion leaders’ influences in the Chinese fashion market. In International Conference on Fashion communication: between tradition and future digital developments (pp. 118-132). Cham: Springer International Publishing.