【主讲】王燕淘 西北大学市场营销系博士

【主题】Social Interaction and Consumption Expansion: An Empirical Investigation 

社交互动和消费扩张：一个实证调查

【时间】2011-10-20（周四）13:30-15:30

【地点】清华经管学院  伟伦楼406室

【语言】中文

【主办】清华大学市场营销系、中国企业研究中心

摘要如下：

Social interaction has been gradually recognized as playing an important role in consumers’ consumption decisions making. For example, research has shown that friends and family members can influence when consumers play golf (Hartmann, 2010) and when and what television programs to watch (Yang et al., 2010). However, little is known about whether social interaction among friends affects total consumption. A key hurdle to the exploration of this question is the difficulty of tracing a consumer’s changing friendship status over time and the difficulty of recording consumption decisions over time.

In this paper, I investigate the interplay between friendship and consumption and provide empirical evidence regarding how social interaction affects consumption. I take advantage of a unique dataset that includes consumers’ detailed consumption decisions and referrals of friends. I augment this data with surveys to map out each consumer’s evolving friendship network. I then develop a Bayesian hierarchical model that allows me to link friendship with consumption decisions. I use an instrumental variables approach to address the common problem of endogeneity due to simultaneity in the context of social interaction.

Applying the model to the setting of fitness class attendance, an activity that usually does not require interaction with others, I find strong evidence of consumption expansion due to social interaction among friends. Further, I identify two sources of expansion: one is due to coordination with friends to attend the same classes hence enjoying companionship; the other is due to socialization with friends outside the class venue which raises the salience level of the activity.

In addition, I use individual level coefficient to characterize the effects of social interaction by one's position in his friendship network. I find that those who occupy a relatively peripheral position in his network only increase his consumption when he has two or more friends. When he has only one friend at the studio, he, to a great extent, tends to reschedule his solitary consumption to coordinated consumption. In contrast, those members who occupy a relative central position in their network manage to increase class consumption even when there is only one friend. I conjecture this is because strong interaction with the close friend outside the class venue significantly raised salience level of the activity, hence increasing his solitary consumption as well. Overall, those who are at the peripheral of their network experience up to 26% increase in consumption annually. Those who are at the central of their network experience up to 40% increase in consumption.