Selected Publications
Different but Equal? A Field Experiment on the Impact of Recommendation Systems on Mobile and Personal Computer Channels in Retail
( Lee, Dongwon | Gopal, Anandasivam | Park, Sung-Hyuk )INFORMATION SYSTEMS RESEARCH2020-09
Abstract
The benefits of recommendation systems in online retail contexts have received much attention in prior work. Much of this work has been conducted in personal computer (PC)-based settings, although mobile devices are becoming increasingly central to the online shopping experience. It remains to be examined if the effects of recommendation systems in retail differ across these two channels, in terms of customer-level decision outcomes. In this paper, we examine these differences in some detail, studying how product views and sales attributed to a recommendation system are different across mobile and PC-based channels. Further, we examine how the effect of a recommendation system across channels influences sales diversity, an important outcome in the retail industry. We conduct our analysis using a randomized field experiment, conducted in partnership with an online retailing firm in South Korea, where the experimental treatment is access to a recommendation system. Our results show that the use of recommendation systems enhances customer-level outcomes, such as views and sales of recommended products, clickthrough rate, and conversion. More importantly, the marginal impacts of the recommendation system are significantly higher for mobile users, indicating that the higher search costs imposed through mobile devices are more effectively reduced through recommendation systems. With respect to sales diversity, we observe that although the mobile channel leads to more diverse sales, we see no interaction effects of the recommendation system and mobile use on sales diversity. These results provide boundary conditions for the efficacy of recommendation systems in retail contexts where online sales occur across both PC-based and mobile channels. We discuss the managerial implications of these results for online retailers and conclude with opportunities for further research.
PCAOB international inspections and Merger and Acquisition outcomes
( Kim, Yongtae | Su, Lixin | Zhou, Gaoguang | Zhu, Xindong )JOURNAL OF ACCOUNTING & ECONOMICS2020-08
Abstract
This study examines how PCAOB international inspections of non-U.S. auditors affect international Merger and Acquisition (M&A) outcomes. We find that clients of inspected auditors are more likely to become acquisition targets after the public disclosure of auditor's inspection report. We also find that deal completion is more likely and deal announcement returns are higher if deals involve targets with auditors for which inspection reports are available. Engagement deficiencies and unremediated quality control deficiencies identified in inspection reports weaken the positive effect of PCAOB oversight on M&A outcomes. Collectively, our results suggest that PCAOB oversight reduces information uncertainty in M&A deals.
Strategic decompositions of normal form games: Zero-sum games and potential games
( Hwang, Sung-Ha | Rey-Bellet, Luc )GAMES AND ECONOMIC BEHAVIOR2020-07
Abstract
We introduce new classes of games, called zero-sum equivalent games and zero-sum equivalent potential games, and prove decomposition theorems involving these classes of games. Two games are "strategically equivalent" if, for every player, the payoff differences between two strategies (holding other players' strategies fixed) are identical. A zero-sum equivalent game is a game that is strategically equivalent to a zero-sum game; a zero-sum equivalent potential game is a potential game that is strategically equivalent to a zero-sum game. We also call a game "normalized" if the sum of one player's payoffs, given the other players' strategies, is zero. One of our main decomposition results shows that any normal form game, whether the strategy set is finite or continuous, can be uniquely decomposed into a zero-sum normalized game, a zero-sum equivalent potential game, and an identical interest normalized game, each with distinctive equilibrium properties.
Impact of customers' digital banking adoption on hidden defection: A combined analytical-empirical approach
( Son, Yoonseock | Kwon, Hyeokkoo Eric | Tayi, Giri K. | Oh, Wonseok )JOURNAL OF OPERATIONS MANAGEMENT2020-06
Abstract
The implementation of digital channels as avenues for economic transactions (e.g., online and mobile banking/FinTech) has shifted the paradigm of customer-bank interactions, providing unprecedented opportunities for both parties. The prevailing belief is that digital banking has several advantages, such as lower costs and higher information transferability for customers. These benefits can also promote competition between banks given customers' predilection for "multi-homing," or engagement with multiple banks. This study investigated the impact of customers' digital banking adoption on hidden defection, in which customers purchase financial products from competing banks instead of their primary banks. To this end, we developed an analytical model to provide insights into the effects of digital banking adoption while taking customers' multi-homing behaviors into consideration. We then conducted a series of empirical analyses using comprehensive individual-level transaction data to provide evidence of hidden defection. Our findings indicate that customers with higher loyalty exhibit greater hidden defection after digital banking adoption. Customers who engage primarily with personal-service channels (e.g., branches) show stronger hidden defection than do self-service channel (e.g., ATMs) users, and this effect is more prevalent among loyal customers. Our results provide valuable implications for omni-channel services in a market characterized by multi-homing behavior of customers.
Quality Information Disclosure and Patient Reallocation in the Healthcare Industry: Evidence from Cardiac Surgery Report Cards
( Yoon, Tae Jung )MARKETING SCIENCE2020-05
Abstract
In a healthcare industry with capacity constraints, the best healthcare providers are often congested after quality information disclosure. This congestion can lead to the reallocation of urgent patients to low-quality healthcare providers. The reallocation can have a detrimental impact on the overall patient survival rate if sicker patients benefit more from the best providers. This paper provides the first empirical evidence regarding this problem in the context of the publication of cardiac surgery report cards. I find that these report cards can have a negative impact on positive assortative matching between patients and surgeons because of a reallocation of high-risk patients to low-quality surgeons. Despite the quality improvement in response to these report cards, such patient reallocation can still be a problem, conditional on the improved quality, and, thus, should not be ignored.
