# Ratio Statistics

This feature requires the Statistics Base option.

The Ratio Statistics procedure provides a comprehensive list of summary statistics for describing the ratio between two scale variables.

You can sort the output by values of a grouping variable in ascending or descending order. The ratio statistics report can be suppressed in the output, and the results can be saved to an external file.

- Example
- Is there good uniformity in the ratio between the appraisal price and sale price of homes in each of five counties? From the output, you might learn that the distribution of ratios varies considerably from county to county.
- Statistics
- Median, mean, weighted mean, confidence intervals, coefficient of dispersion (COD), coefficient of variation (COV), median-centered coefficient of variation, mean-centered coefficient of variation, price-related bias (PRB), price-related differential (PRD), standard deviation, average absolute deviation (AAD), range, minimum and maximum values, and the concentration index computed for a user-specified range or percentage within the median ratio.

## Data considerations

- Data
- Use numeric codes or strings to code grouping variables (nominal or ordinal level measurements).
- Assumptions
- The variables that define the numerator and denominator of the ratio should be scale variables that take positive values.

## Obtaining Ratio Statistics

This feature requires the Statistics Base option.

- From the menus choose:
- Select a numerator variable.
- Select a denominator variable.

Optionally:

- Select a grouping variable and specify the ordering of the groups in the results.
- Choose whether to display the results in the Viewer.
- Choose to add an N keyword to the PRINT subcommand. The setting adds the sample sizes to the statistics table in the output.
- Choose whether to save the results to an external file for later use, and specify the name of the file to which the results are saved.

This procedure pastes RATIO STATISTICS command syntax.