多數和少數訊息來源在不同涉入程度下對產品判斷的影響機制及效果:勸服變數的多重角色觀點

Abstract

本文主要應用勸服變數的多重角色觀點，利用兩個實驗來分別探討在高、中、低三種涉入程度下，多數/少數訊息來源是以何種機制來影響消費者的產品態度。實驗一主要是在受測者對產品無初始態度的情境下探討，而實驗二則考慮當多數或少數人對產品的意見與受測者的產品態度相反和相同的情況。 當受測者對目標產品(洗髮精)無初始態度時，只有當多數/少數訊息來源具高可靠度，多數/少數訊息來源才會影響高涉入受測者的產品態度，此時多數/少數訊息來源被視為是中心論點(central arguments)，而且會偏誤資訊處理的方向；而當受測者的涉入程度為低時，無論多數/少數訊息來源的可靠度為何，多數/少數訊息來源皆會影響低涉入受測者的產品態度，多數/少數訊息來源被視為周邊線索，直接影響產品態度；而當涉入程度為中度時，多數訊息來源會比少數訊息來源引起較多的訊息處理。 當受測者對目標產品(洗髮精)有初始態度時，受測者只接觸到具高可靠度的訊息來源，在高、低涉入情況下，多數/少數訊息來源的影響效果仍與實驗一結果相同，然而在中涉入的情況下，多數訊息來源與少數訊息來源都可能會引起較多的訊息處理，即在相反意見的情境下，多數訊息來源會比少數訊息來源引起較多的訊息處理；在相同意見的情境下，少數訊息來源會比多數訊息來源引起較多的訊息處理。

Appling the perspective of multiple roles of persuasion variables, two studies investigate the mechanisms underlying the effects of source status (majority vs. minority) on product attitudes under different involvement levels (high vs. moderate vs. low). Specifically, Experiment 1 examines the persuasive process of source status when participants have no prior attitudes, whereas Experiment 2 examines this process when participants receive majority- or minority-advocated messages consistent or inconsistent with their prior attitudes. When participants have no prior attitudes toward the target product, source status influences high-involvement participants’ attitudes by serving as a central argument and by biasing processing only when the source offers high credibility. When involvement is low, source status directly influences participants’ attitudes by serving as a peripheral cue, regardless of credibility. When involvement is moderate, the majority source prompts greater message scrutiny than the minority source. Among participants with prior attitudes, exposed only to high-credibility sources; the effects of source status remain the same for high and low involvement. However, with moderate involvement, either a majority or a minority source can enhance message scrutiny. The minority source induces greater message scrutiny than the majority source in the congruent condition, whereas the opposite is true in the incongruent condition.