Quality Adjustment in the CPI: Women’s Top : U.S. Bureau of Labor Statistics

An official website of the United States government

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Bureau of Labor Statistics > Consumer Price Index > Methods > Quality Adjustment

Quality Adjustment in the CPI: Women’s Tops

Item definition

The Entry Level Item (ELI) category of Women’s Tops is part of the index for Women’s Suits and Separates and includes all types and styles of jackets, sweaters, and tops. In this factsheet, we examine the regression model used in the quality adjustment of price data for women’s tops.

CPI sample

The sample used for the new hedonic model included approximately 3,800 observations. This model was constructed using web-based information. This was due to restrictions being put on data collection during the COVID-19 pandemic. Previous models had a mix of store and website collected data. Around 62 percent of prices were from March or April of 2022. There were over 400 different outlets in the sample and about 700 unique clothing brands. Private brands made up most of the sample, accounting for almost 63 percent of all observations. National brands made up approximately 32 percent of sample, with exclusive and miscellaneous brands making up the remaining 5 percent.

Current Model

Table 1 presents the details of the estimation of the current model used to quality adjust women’s tops.

Table 1. Parameter estimates for the hedonic regression for women's tops
Variable	DF	Parameter Estimate	Standard Error	t Value	Pr > \|t\|	Tolerance Statistic
Intercept	1	3.69575	0.02203	167.79	<.0001
Fiber (continuous): Cashmere	1	0.00914	0.0007	13.12	<.0001	0.88195
Fiber (continuous): Wool	1	0.00754	0.00078	9.65	<.0001	0.83974
Fiber (continuous): Silk	1	0.01262	0.00077	16.33	<.0001	0.93207
Fiber (continuous): Linen	1	0.00266	0.00063	4.19	<.0001	0.94772
Fiber (continuous): Cotton	1	-0.00104	0.00018	-5.9	<.0001	0.77818
Fiber (continuous): Nylon	1	0.00261	0.00058	4.48	<.0001	0.87891
Fiber (continuous): Spandex	1	-0.00919	0.00247	-3.72	0.0002	0.78222
Fiber (continuous): Polyester or Rayon		Base
Brand/Label Category: Exclusive	1	1.49982	0.11232	13.35	<.0001	0.52502
Brand/Label Category: National	1	0.3101	0.01765	17.57	<.0001	0.60751
Brand/Label Category: Miscellaneous	1	-0.13011	0.0354	-3.68	0.0002	0.74287
Brand/Label Category: Private		Base
Type of Item Priced: Lined Jacket	1	0.78772	0.04714	16.71	<.0001	0.89665
Type of Item Priced: Unlined Jacket	1	0.67364	0.03663	18.39	<.0001	0.87873
Type of Item Priced: Cardigan	1	0.30478	0.0254	12	<.0001	0.71357
Type of Item Priced: Sweater	1	0.28637	0.02641	10.84	<.0001	0.65721
Type of Item Priced: Open-Front Shirt	1	0.28257	0.02158	13.1	<.0001	0.73155
Type of Item Priced: Vest	1	0.31848	0.06931	4.6	<.0001	0.94834
Type of Item Priced: Activewear Top	1	-0.1138	0.02971	-3.83	0.0001	0.87446
Type of Item Priced: Sweatshirt	1	0.21875	0.03023	7.23	<.0001	0.81264
Type of Item Priced: Pullover Top or Blouse		Base
Sleeve Length: Short Sleeves or Sleeveless	1	-0.24376	0.01644	-14.83	<.0001	0.69912
Sleeve Length: Long or 3/4 Length Sleeves		Base
Form of Closure: Pullover Partly Opens with Fastener	1	0.17078	0.02333	7.32	<.0001	0.89625
Form of Closure: Pullover with No Fastener		Base
Size Range: Juniors or Juniors Plus Size	1	-0.29995	0.03159	-9.49	<.0001	0.94782
Size Range: Misses, Petites, or Plus Size		Base
Fabric Design: Solid Color	1	-0.08657	0.01357	-6.38	<.0001	0.9351
Fabric Design: Multicolor or Printed		Base
Details/Features: Embroidery (Non-Logo)	1	0.21854	0.04455	4.91	<.0001	0.969
Details/Features: Trim, Lace, or Ruffles	1	0.14981	0.02614	5.73	<.0001	0.95425
Details/Features: Sequins, Beads, Rhinestones, or Gems	1	0.16626	0.04928	3.37	0.0007	0.97376
Details/Features: Iron-on/Decal/Screen Print	1	-0.09597	0.0317	-3.03	0.0025	0.83754
Details/Features: Cable Knit (Full or Partial)	1	0.14095	0.05072	2.78	0.0055	0.89364
Details/Features: No Details/Features		Base
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 women’s tops were introduced into the CPI in March 1995. However, at this time women’s tops were separated into three models:
- Women’s Sweater and Sweater Vests
- Women’s Shirts, Blouses, and Other Tops
- Women’s Tailored and Untailored Jackets
In 2006, Women’s Sweater and Sweater Vests was combined with Women’s Shirts, Blouses, and Other Tops were combined into a single model
- Women’s Tailored and Untailored Jackets still had its own model at this point in time

June 2017 was the first time a single model was used to encompass all of Women’s Tops
Type of item (cardigan, sweater, etc.), brand category, and fiber were a few of the characteristics that received a significant amount of focus in the development of this model
The adjustments for type of item have remained fairly consistent over the years. Cardigans, sweaters, jackets (lined and unlined), open-front shirts, and vests have regularly appeared in models for women’s tops.
- This model contained an adjustment for sweatshirts, which has not appeared in a women’s tops model since 2006.
- An adjustment for activewear is also a new feature, as activewear was only recently moved into the Women’s Tops ELI.
Certain fibers no longer appear to have as much influence on price as they previously did. For example, acrylic, ramie, and acetate used to regularly appear in models until around 2011.
Juniors is the only size that has a large influence on price. This and previous models have been unable to find a significant difference in price between misses, petites, and plus sizes.
Specific details/features continue to be price-determining characteristics for women’s tops. These include trim, lace, ruffles, sequins, beads, rhinestones, gems, and embroidery.
- Other details/features included in this model are cable knit and iron-on/decal/screen print. Cable knit has not appeared in a model since 2006. This is the first time iron-on/decal/screen print has appeared in a women’s tops model, although it has a relatively small parameter estimate.

Data

Access data for Women's suits and separates 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: February 22, 2023