The Data Analysis System (DAS) is a web-based software application that provides public access to NCES survey data. The DAS allows users to produce tables and to estimate covariance analyses from NCES data sets. There is a separate DAS for each data set, but all have a consistent interface and command structure. Each DAS contains a detailed description of how each variable was created, and includes question wording for items coming directly from the interview. Users can create programming instruction files, run tables and regressions, and view output using a web browser.
Each DAS runs in two modes - Tables and Covariance Analysis. In the Tables mode, the DAS will create a table of estimates, corresponding standard errors that are calculated by taking into account the complex sampling designs used in NCES surveys, and weighted sample sizes for the estimates. In the Covariance Analysis mode, the DAS will generate output for a weighted least squares regression or logistic regression.
