Hello! I’m Si ZUO 左思

Welcome to My Site

I am a third-year Ph.D. in Strategy and Business Economics, Johnson Graduate School of Management & Economics Department, Cornell University. 

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My research interests are industrial organization, online markets, and platforms.

CV

Building Reputation on Online Platforms, with Yangguang Huang and Chenyang Li

Abstract:

Many online platforms operate reputation systems to collect reviews and transmit quality information about firms and products. A high-quality firm has an incentive to set a low introductory price because it can accumulate favorable reviews from sales and signal high quality. We introduce the reputation system into the classical model with asymmetric quality information and consider a dynamic setting. 
Using data from Zaihang, a consulting service platform, we show empirical evidence that experts with high unobserved ability indeed adopt low introductory prices in practice.  Also, the high-ability experts have a rising price path and declining sales path from the initial to later periods. In addition, more intense competition has negative impacts on high-ability experts' first-period reputation-building up process.  Our findings provide implications for the design of reputation systems on online platforms.

setting. A high-quality firm has an incentive to set a low introductory price because it can accumulate favorable reviews from sales and signal high quality.

Stores Going Online: Market Expansion or Cannibalization? , with Yangguang Huang and Chenyang Li

Abstract:
With the rise of e-commerce, more and more chain stores have opened online sales channels. For one chain, there are usually one online store and many offline stores. Online stores may cannibalize the sales of the existing physical stores because of their advantage in lower shopping costs. On the other hand, the online sales channel is usually a tool for advertisement, which may expand the offline store's market. From our novel daily revenue data of 380 offline stores from 2016 to 2020, we identify the countervailing cannibalization effect and the informative effect of opening up online branches on offline stores. We first use exogenous demand shocks (weather, Covid-19, and online shopping festivals) to provide solid evidence of these two effects. We then separately estimate these two effects by a structural model. We find that the cannibalization effect dominates the informative effect in most cases. The electronics category has the largest cannibalization effect, while the cosmetics and jewelry category has the smallest.

Externality Within the Shopping Mall, with Tianli Xia

Abstract:
Many papers show there exists the externality among shops within a mall or shopping street, but there is little study about how the externality changes across space and categories. Using the novel daily data of 380 stores in a large mall from 2016 to 2020, we identify the externalities from anchor stores using the anchor stores' promotional events. We adopt a new IV for a store's promotion: the promotional events of the other stores under the same brand in the same city. Then we show how the externalities vary across floors, distance, and store categories, which is unique to the existing literature. Finally, we use simulations to illustrate how rent contracts and store allocations could internalize the externalities among shops and provide managerial suggestions.

Teaching