Dissecting consumer behavior has already proven to be a difficult task this holiday, and it just got even more confusing.
Analytics firm ShopperTrak on Tuesday released Black Friday weekend results that showed a sales increase of 1 percent, and a traffic decline of 4 percent. The figures were a complete reversal from data released by the National Retail Federation over the weekend, which said that holiday spending fell nearly 3 percent, but the number of shoppers rose about 1 percent.
What's behind the discrepancy?
(Read more: US online sales fuel retail gains Thanksgiving weekend)
The differences, according to ShopperTrak founder Bill Martin, lie in the methodology. While NRF's Kathy Grannis cautioned against comparing the two surveys, below are some of the key differences in how the firms compile the data:
- The National Retail Federation data include both online and in-store shoppers but do not separate the two; ShopperTrak only accounts for brick-and-mortar traffic and sales.
- The National Retail Federation polled 4,464 consumers via Prosper Insights to ask them about their shopping behavior and spending, which it said has a margin of error of plus or minus 1.5 percent; ShopperTrak has counting devices placed in more than 50,000 brick-and-mortar stores across the U.S. that count shoppers entering stores. It gets sales data from the individual retailers' sales logs.
- NRF includes items that are sold at the necessity level, including gas and grocery store goods; ShopperTrak focuses more on the disposable income level, such as general merchandise and furniture.
(Read more: Winners and losers of Black Friday's megadeals)
Despite contrasting Black Friday data, the two groups do agree on some key points this holiday.