東京大学マーケティング・ワークショップ

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ＪＩＭＳ「消費者・市場反応の科学的研究部会」

（通称：東大マーケティング・ワークショップ）今年度第3回会合

日時:

9月13日(月曜日)　18:00 〜 20:00

場所:

東京大学経済学研究科棟　12階　第1共同研究室

テーマ:

『Returns to Reputation in Online Markets』　＊セミナーは英語になります。

キーワード:

インターネット、オークション、評判、リスク

講師:

Prof. Kirthi Kalyanam (Associate Professor of Marketing, Santa Clara University, USA)

* Prof. Kirthi Kalyanam received his Ph.D. from Purdue University (USA). He is J.C. Penney Research Professor, and Retail Management Institute Director, E-Business Initiatives at Santa Clara University.

概要:

eBay and other online auction sites have developed infrastructures that buyers can use to provide ratings and feedback about their transaction experiences with sellers. Buyers can then view a scorecard that summarizes these ratings. Therefore, in the online world the buyers can observe reported trustworthiness, or "reputation", for each seller. This research develops an assurances framework to assess the effect of a seller's reputation on the closing price of an auction at eBay's website. The framework provides hypotheses about how information-based assurances (particularly feedback scores and the seller's provision of information about the product) may be used by buyers to reduce their trading risks. The hypotheses are tested using data on auctions of Palm Pilot personal digital assistants. Of the various measures of reputation available to them, buyers use the overall feedback score and the % of negative comments received by the seller. It is found that the higher the seller's reputation the higher is the average closing price of the auction, in other words, a return on reputation (ROR). It is also found that negative comments are weighted more heavily than positive ones which would be consistent with both Prospect Theory. The assurance offered by reputation is more salient among quality sensitive buyers who are looking for a new machine versus a used one. A high level of information about the merchandise also provides an assurance and reduces the buyer's risk. When faced with a high level of information, quality sensitive buyers rely less on the sellers reputation score for assurance (a three way negative interaction between quality sensitivity, reputation and high information). The seller of a Palm Pilot with a high reputation can expect to receive as much as 19% more for the item than if he had a low reputation score. Thus the reputation infrastructure rewards good behavior with positive economic outcomes and sustains a virtuous cycle in the online ecosystem. It is argued that the market for assurances is a significant contributor to eBay's great success and is also essential to the optimal functioning of any online market.