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RATIO Procedure

The RATIO procedure produces ratio estimates and their standard errors for sample surveys and other clustered data applications. The numerator and denominator variables can be continuous or categorical.

RATIO computes standardized means according to the method of direct standardization. The standardizing weights are assumed to be known.

For continuous variables, RATIO computes a ratio of weighted sums. If VAR1 and VAR2 denote the numerator and denominator variables respectively, and the variable WT denotes the weight, then the ratio estimate is computed by summing over the analysis observations on the input data set, as follows:

For categorical variables, RATIO computes a ratio of weighted counts of individuals falling into a specified response category, as follows:

1) Any positive integer is a valid response category.

2) The numerator is the weighted sum of individuals who gave the specified integer response to the numerator variable.

3) The denominator is the weighted sum of individuals who gave the specified integer response to the denominator variable.

RATIO estimates can consist of a continuous numerator variable and a categorical denominator variable or vice versa. However, within one call to RATIO, all numerator variables must be of the same type, and all denominator variables must be of the same type.

Procedure Enhancements:

Analysis of multiply imputed data has been implemented to produce all estimates, variances and tests of hypothesis.

The CLASS statement is available in RATIO.

Estimates of confidence limits for ratios are now produced by default in the TABLECELL group