Complete the following steps to specify the columns of data that you want to analyze.
- In Response, enter the column of numeric data that you want to explain or predict. The response is also called the Y variable.
- In Free predictors, enter the columns of numeric data that may explain or predict changes in the response. The predictors are also called X variables. These predictors will be included in the subset models depending on their R2 value. You can specify up to 31 variables.
- (Optional) In Predictors in all models, enter the columns that contain the variables you want to include as predictors in every model. The columns you enter here must not be listed in Free predictors. If you are analyzing a large data set with more than 25 predictors, consider including certain predictors here in order to decrease the number of free variables and speed up the computations. The maximum number of variables which can be entered is equal to 100 minus the number of variables entered in Free predictors.
In this worksheet, Strength is the response and contains strength measurements for a sample of plastic pipe. Time, Pressure, Temp, and Humidity are predictors and may explain differences in strength.