Assess model performance. Both the Multiple R-Squared and Adjusted R-Squared values are measures of model performance. Possible values range from 0.0 to 1.0. The Adjusted R-Squared value is always a bit lower than the Multiple R-Squared value because it reflects model complexity (the number of variables) as it relates to the data, and consequently is a more accurate measure of model performance. Adding an additional explanatory variable to the model will likely increase the Multiple R-Squared value, but decrease the Adjusted R-Squared value. Suppose you are creating a regression model of residential burglary (the number of residential burglaries associated with each census block is your dependent variable, y). An Adjusted R-Squared value of 0.84 would indicate that your model (your explanatory variables modeled using linear regression) explains approximately 84% of the variation in the dependent variable, or said another way: your model tells approximately 84% of the residential burglary "story".