2019年8月22日開催 公開研究会開催報告 （研究チーム：「グローバルコミュニケーション戦略」「社会経済制度の理論研究と実証分析」）

2019年8月22日(木) 公開研究会を開催しました。

【テーマ】A Dynamic Structural Model of Endogenous Consumer Reviews in

　　　　　Durable Goods Markets

【報告者】石原 昌和 氏（ニューヨーク大学スターン・スクール・オブ・ビジネス 准教授 ）　　　　　　

【日　時】 2019年8月22日（木）16:00～18:00

【場   所】 中央大学多摩キャンパス 2号館4階 研究所会議室3

【要　旨】

In the seminar Prof. Masakazu Ishihara discussed his interesting paper, Ishihara and Liu (2019). The outlines of his presentation were as follows. Consumers commonly seek information from critic and consumer reviews when new product quality remains uncertain. However, consumer reviews are endogenous and may be subject to potential biases (e.g., self-selection). Thus, he and his co-author propose a new dynamic structural model where

forward-looking consumers learn about quality from review ratings, make purchase decisions, and report consumer ratings post-purchase. In particular, the review-reporting component links unobserved heterogeneity in product valuation with consumer ratings, and allows them to examine the effect of pre-purchase quality beliefs on reported ratings. They apply the model to the US video game market. Their data consist of aggregate-level

preorder sales, post-release monthly sales and prices, and individual-level critic and consumer ratings for 31 games released on SONY PlayStation 3. The preorder sales help identify the causal effect of review ratings on sales. Using the estimates, they quantify the effect of a price promotion during the preorder period. They demonstrate that if they ignore the endogeneity of consumer reviews, the effect of the price promotion can be over-estimated. This is because the price promotion attracts less enthusiastic consumers, which lowers the average consumer ratings subsequently. They further quantify the contributions of critic and consumer reviews to firms' profits. Attendants enjoyed the sophisticated presentation and lively discussion.