By Sarah Flood
The team at IPUMS is excited to introduce something brand new! ATUS-CPS Linking Counts is an interactive tool for exploring the number of ATUS respondents who can be linked to specific CPS months. We know that linkages between ATUS and CPS have great potential for enabling exciting new research, but we also know firsthand how hard it can be to wrap your head around the panel component of the CPS, the relationship between ATUS and CPS, and the many possibilities for linking them. Even researchers who have deep knowledge of the ATUS and CPS may still wonder whether there is a sufficient number of cases to conduct an analysis of interest. This new tool helps address all of these challenges. It very quickly allows you to view the number of ATUS respondents who should appear in each CPS month and determine if there is sufficient sample size for a particular application of linked ATUS-CPS data.
Linking ATUS and CPS data enables an incredible wealth of research questions. This tool allows users to specify and view different linking scenarios to assess the feasibility of various ATUS to CPS linkages. For example, you may want to investigate the relationship between food security in the CPS with shopping or eating-related behavior in the ATUS. This interactive tool would allow you to select only years of ATUS data that contain, for example, the Eating and Health module and view the CPS months in which the Food Security supplement was fielded to assess the sample sizes for your desired analysis. Figure 1 shows how you would select ATUS years of interest and find information about which ATUS modules were fielded in each year.
Figure 1. Selecting ATUS Years of Interest
Once ATUS years have been selected, the calendar grid displays the number of ATUS respondents from each year who may be observed in each CPS month (see Figure 2). Let’s interpret what we see in Figure 2. In the bottom row, which represents all months of data from the 2021 CPS, you can see that 766 respondents from the 2021 ATUS participated in the January 2021 CPS. The help text that appears in the pop-up box when you hover on a given year-month combination tells us that this was two to five months prior to the final CPS interview. Moving across the row, we see that 44 people in the 2021 ATUS completed the CPS in October 2021. There are no 2021 ATUS respondents in November or December of 2021. This is because people completing the CPS in November (December) 2021 wouldn’t have been eligible for the ATUS until January (February) 2022. Extending this logic, we would expect to observe 2021 ATUS respondents in the last two to five months of the 2020 CPS. If we look at the 2020 row, we can see that only 8 ATUS respondents in 2021 finished the CPS in August of 2020, the earliest month in 2020 where we would expect to observe 2021 ATUS respondents. A number of 2021 ATUS respondents completed the CPS in September to December 2020 as well.
Figure 2. ATUS-CPS Linking Counts Calendar Grid
The “Show CPS Supplement Labels” option displays the timing of CPS supplement data on the calendar grid. The frequency with which CPS supplements are fielded varies from multiple times per year in some years (e.g., Tobacco Use) to annually (e.g., the Annual Social and Economic Supplement and Education) to periodically (e.g., Work Schedules).
Using linked ATUS-CPS data will require that you make decisions about what kind of time gap between the CPS and the ATUS you are willing to accept. The tool enables researchers to specify different linking windows of interest to see, for example, linking counts only for the final month of ATUS respondents’ participation in the CPS or any time they appeared in the CPS. Figure 3 shows the linking options for which we provide linkage counts. Additional details are available in our documentation on linking ATUS and CPS data.
Figure 3. ATUS to CPS Linking Options
In addition to displaying the number of ATUS to CPS linkages you might expect, the tool also allows you to download the linking counts as a csv file. This means that as you’re developing your code for linking ATUS and CPS data, you will know – and can even reference in code – the actual (or in some cases, maximum) number of linkages you should expect.