Quality Adjustment in the CPI: Men’s & Women’s Athletic Footwear

Item definition

Both Men’s Footwear and Women’s Footwear include categories for athletic footwear. Along with their respective categories for shoes, boots, sandals, and slippers, they are part of the overarching category of Footwear. Here, we examine the hedonic regression model used in the quality adjustment of price data for athletic footwear. (Since men’s and women’s athletic footwear is similar, they are grouped to create a single hedonic regression model.)

CPI sample

The sample used for the current hedonic model for men’s and women’s athletic footwear included 1,132 observations from an extract of CPI data for the months of May and June 2022. This model was constructed using web-based information due to restrictions on data collection during the COVID-19 pandemic, unlike models from the past that had a mix of store and website data. There were more than 150 unique brands in the sample, with the top five brands accounting for about 50 percent of the sample. Additionally, the sample included more than 100 outlets of both the brick and e-commerce variety; the top five outlets comprised about 30 percent of the sample.

Current Model

Table 1 presents the details of the estimation of the current model used to quality adjust men’s and women’s athletic footwear.

Note: This model contains control variables for type of business, type of store, and geographic region, but they are not used in adjustments.

Summary notes

• Quality adjustments derived from hedonic regressions for men’s and women’s athletic footwear were first incorporated into the CPI in 1995, though in separate models. In 2000, the models were combined to create a single athletic footwear model. Since then, the model has been updated four times.

• The athletic footwear model is distinct from the models for boots, shoes, sandals, and slippers in a number of ways.

  • The athletic footwear model combines men’s and women’s data to create a single model, as athletic footwear tends to be much more similar between genders than other kinds of footwear.

  • One of the key adjustments in any model for boots, shoes, sandals, and slippers is the outsole material, but since most athletic footwear has a synthetic outsole, it’s not a factor here.

  • The athletic footwear model has adjustments for specific brands. This is because athletic footwear tends to be dominated by a few big brand names, which is not the case for other types of footwear. As mentioned above, out of more than 150 distinct brands in the sample, the top five account for roughly half the quotes. And sometimes, a particular brand has pricing that is so distinct that it makes more sense to separate it from other brands.

• The details and features that are included in athletic footwear hedonic models have changed over the years. Past models have included adjustments for height, brand-specific technologies, and even celebrity endorsements. As consumer tastes shift, however, these elements rise and fall in relevance.

Data

Access data for Footwear in our online database.

Additional information

Additional information may be obtained from the Consumer Price Index Information Office by email or calling 202-691-7000. Information on the CPI's overall methodology can be found in the BLS Handbook of Methods.

Last Modified Date: March 16, 2023