The Market-Average Effects in a Non-Dominant Two-Dimensional Choice Set

Abstract

本研究的目的在探討在雙屬性，無絕對優勢的選擇組合中的最佳選項為何。過去有兩大不同觀點：選項相對位置的看法，認為中點是被視為最不極端的點，因此會被選為妥協選項。而屬性平衡效果則提出：一個在兩個屬性上的得分相同的選項，即便它不是中點，也會被選為妥協點。本研究則提出一個全新的市場平均效果與前述兩種看法相抗衡。這個觀點認為，只要市場平均選項出現在組合中，不論它是在端點，或是組合中另有屬性平衡選項，市場平均選項都會成為妥協點。 本研究採行了三個實驗以驗證假設。從實驗一的資料與預期的相同，市場平均選項不論在雙選項或是三選項的組合中，都是最佳的選擇。而實驗二的結果證明了市場平均選項是比屬性平衡選項更受歡迎的假設。此外，虛擬的市場平均選項也是一個有效的定錨點的預測也由實驗三的結果部分獲得證實。實驗的結果、發現及其理論應用則在研究後半討論之。

This research aims at exploring the best option in a non-dominant two-dimensional choice set. Prior studies have two different views. The relational properties of choice alternatives state that the middle option is viewed as the least extreme, compromise option. The theory of attribute-balance effects proposes that an option with equal attribute rating will be perceived as the compromise even when it is not the middle option. A brand new concept of market-average effects is demonstrated to compete with these two views. It is argued that wherever a market-average alternative presented, whether it is an adjacent option or with a balanced alternative, it is the compromise. Three experiments are employed to test the hypotheses generated in this research. Data from experiment 1 confirm the proposition that a market-average alternative is the most attractive option both in binary and trinary sets. The results of the second experiment are consistent with the hypothesis that a market-average alternative is more preferred than a balanced alternative. The prediction that a virtual market-average alternative is an influential anchoring point is partly supported by experiment 3. Theoretical implications of the findings are discussed.