免費贈品促銷的產品互補性對價值貶低之影響

The Impact of Item Complementarity in Freebie Promotions on Value Discounting

根據價值貶低假說，在免費贈品促銷結束、銷售之主商品和免費贈品單獨販售時，消費者對於主商品、免費贈品的願付價格會減少。免費贈品促銷雖然可能有助於增加短期銷售，但就長期而言，卻可能減少促銷組合中品項的吸引力，故探討贈品促銷的影響，以及哪些因素可能會影響價值貶低效果，有其重要性。本研究探討免費贈品促銷中主商品與贈品的互補性，是否影響後續的價值貶低效果，並檢視可能的中介機制。實驗一和實驗二證實，功能相關的互補，相較於非互補，會減少對於主商品和贈品的價值貶低，且促銷吸引力和知覺風險中介了功能相關互補性對於價值貶低效果的影響；實驗三則證實，情感基礎的互補也會削弱價值貶低效果，然此一效果僅透過促銷吸引力所中介。研究結果對於學術和相關實務上的運作有所貢獻。

According to the value-discounting hypothesis, freebie promotions can lower consumers' willingness to pay (WTP) for both the focal and freebie products when these products are later sold separately. Freebie promotions might increase sales in the short run, but damage the attractiveness of the items in the promotional packages over the long run. Therefore, exploring the impact of freebie promotions and the relevant factors that might influence the value-discounting effect are highly important. This research examines how the complementarity of the items in freebie promotions influences value discounting of the focal and freebie items, and it explores possible mediating mechanisms. Two experiments demonstrate functionally-related complementary (vs. non-complementary) promotions reduce value discounting of both the focal and freebie items. Moreover, promotional attractiveness and perceived risk mediate the impact of functionally-related complementarity on the value-discounting effect. A third experiment provides evidence that affective-based complementarity also produces a similar effect on value discounting, but this acts only through the internal mechanism of promotional attractiveness. The findings have significant implications to both theory and practice.