eligibility for free and reduced-price school meals, respectively. The panel partnered with the Census Bureau to develop model-based estimates for the percentages of public school children who are eligible for free and reduced-price meals. The model was developed in a short period of time and with limited resources, and should be viewed as a proof of concept. The work on developing and evaluating the model led to the identification of research topics that could be used to improve the model in the future should resources become available.
The SAIPE estimation process entails several steps. First, state-level poverty estimates are developed for ages 0-4, 5-17, 18-64, and 65 and older. There are two equations for ages 5-17—one for all children and one for related children. These estimates are based on a weighted average of a direct ACS estimate and a prediction from a regression model. The dependent variable in the model is the ACS 1-year direct estimate.5 Independent variables include the poverty rate from the 2000 census, the tax return poverty rate, the tax return nonfiler rate, a Supplemental Nutrition Assistance Program (SNAP, formerly the Food Stamp Program) participation ratio, and the Supplemental Security Income (SSI) receipt rate. The regression-based and ACS-based estimates are combined, each being weighted according to the associated uncertainty, with the more uncertain estimate having less weight. The poverty ratios obtained are multiplied by population estimates to provide counts of the number of people in poverty, which are controlled to sum to the official national total from the ACS.
Second, county-level estimates are developed. Like the state estimates, the county estimates are based on a weighted average of direct ACS estimates and regression predictions. The dependent variable in each regression model is the log of the number of people in a particular age category in that county as measured by the ACS. Predictor variables (appropriately transformed) include the number of child exemptions claimed on tax returns of people in poverty, the number of child exemptions on tax returns, the number of SNAP benefit recipients, the resident population, and the estimated number of people in the age category in poverty according to the 2000 census. Weighting of the ACS and model estimates
4 This section comes from documentation on the Census Bureau’s website, with some minor editing. See http://www.saipe.gov/did/www/saipe/methods/schools/data/20062008.html.
5 ACS direct estimates are estimates produced for a population group, time frame, and geographic area based only on ACS data and the ACS methods documented by the Census Bureau.