Measuring Quality Growth and Studying Stockout Behavior Using Micro CPI Data

本研究利用保密的消费者价格指数（CPI）微观数据来研究两个问题——消费品的质量改进和企业边际成本的变动以及由于市场波动导致的临时产品库存造成的价格加价。研究的第一部分研究了消费者价格通胀和质量增长的敏感性，以处理与引入新型号的耐用消费品相关的价格上涨。劳工统计局的重新抽样方法可以用来获得关于销售数量如何随模型更替而变化的信息。然后，这些信息被用来衡量新产品的价格上涨有多少应归因于质量改进。研究的第二部分表明，与现有方法相比，关于临时产品库存的信息如何提供有关企业成本和价格在市场周期中如何表现的更直接信息。与成品库存数据相比，缺货数据适用于范围更广、分类更分散的商品。研究表明，价格上涨既可以归因于价格粘性，也可以归因于卖家主动调整价格。本研究结果具有重要的政策意义。在质量改善和消费者价格上涨之间区分价格上涨的能力，对于收集价格信息的目标至关重要。其结果可以直接为用来判断生活水平变化的价格上涨的测量提供信息。调查结果可以为修订劳工统计局的方法提供建议，也可以为劳工统计局提供的其他统计数据提供建议。这项研究的结果也可能对如何衡量通货膨胀产生影响。这可能影响工资合同、社会保障支付、保险中生活成本调整的确定，并最终影响通货膨胀率本身。

This research exploits confidential Consumer Price Index (CPI) micro data, to study two issues---quality improvements for consumer goods and movements in firms' marginal costs and price markups due to temporary product stockouts over market fluctuations. The first part of the research studies the sensitivity of consumer price inflation and, quality growth, to treatment of the price increases associated with the introduction of new models of consumer durables. The BLS' resampling method can be exploited to gain information on how quantities sold change with model turnovers. This information is then used to gauge how much of price increases for new goods should be attributed to quality improvements. The second part of the research shows how information on temporary product stockouts, provide more direct information on how firms' cost and prices behave over the market cycle than existing methods. The stockout data are available for a much wider and more disaggregate set of goods than data on finished inventories. The research shows how price markups can either be attributed to price stickiness or active price adjustments by sellers. Results of this research have important policy implications. The ability to break price increases between quality improvements and consumer price inflation is central to the goals of collecting information on prices. The results can directly inform measurement of price increases used to judge changes in standards of living. The results can yield suggestions for revisions of BLS methods or suggestions for additional statistics the BLS could make available. The results of the research could also have an effect on how inflation should be measured. This could affect the determination of cost living adjustments in wage contracts, social security payments, insurance, and ultimately the rate of inflation itself.