Change from binary response format to event/trial format

Data in binary response format can give the most detail about the order of data collection. When each row contains the result of an individual trial in order, the data has the most results.

However, data in binary response format cannot show an informative pattern on the residuals versus fits plot. If the data have multiple trials at the combinations of the predictor variables in the model, you can change the format of the data to create a meaningful residuals versus fits plot. The residuals versus fits plot can help you assess the model fit and the appropriateness of the link function. If the data do not have multiple trials at the combinations of predictor variables, the residuals versus fits plot is still uninformative.

If the data are in binary response format without a frequency column

1. If the response column does not contain 0 and 1, use Data > Code to create a new response column of zeroes and ones. Use 1 for the event.

2. Choose Stat > Basic Statistics > Store Descriptive Statistics.

3. In Variables, enter the response column.

4. In By variables, enter the predictor variables in the model.

3. Click Statistics.

5. Check Sum and N nonmissing.

6. Click OK.

7. Click Options.

8. Uncheck Include empty cells.

9. Click OK in each dialog box.

The sum column contains the number of events and the N column contains the number of trials. The by variables include the predictor variables.

If the data are in binary response format with a frequency column

1. Choose Stat > Basic Statistics > Store Descriptive Statistics.

2. In Variables, enter the frequency column.

3. In By variables, enter the predictor variables in the model and the response variable.

4. Click Statistics.

5. Check Sum.

6. Click OK.

7. Click Options.

8. Uncheck Include empty cells.

9. Click OK in each dialog box.

10. Press CTRL + E to reopen Store Descriptive Statistics.

11. In Variables, enter the column that contains the sum from the frequency columns, for example SUM1.

12. In By Variables, enter the stored by variable column that contains the response values, for example ByVar1.

13. Click OK.

The first sum column contains the number of events and the second sum column contains the number of trials. The by variables include the predictor variables.