经济与金融系学术讨论会第60期 

时间：2019年5月21日（周二）12:00-13:00 

地点：同济大厦A楼505室 

题目： Shopping time, net product creation, and the productive role of demand 

主讲人：Mario Silva（同济大学经济与管理学院，助理教授） 

Abstract：

I develop a business cycle model which examines the joint determination of shopping time, product creation, and income with both productivity and demand shocks. Shopping helps consumers diversify the consumption basket, and shopping efficiency rises with product availability. The calibration targets the growth rate of varieties economy-wide, the growth rate of the consumption basket at the household level, and the average time spent shopping. A positive demand shock increases shopping time and therefore the measure of consumers for each firm. Incumbents, in turn, raise output and obtain higher matching efficiency, raising productivity. New firms enter, reducing market share of incumbents and their matching rate. The marginal utility of consumption rises both from greater shopping and product availability, amplifying the original demand shock. This channel effectively raises measured productivity and generates positive comovement between shopping time, product creation, and productivity.