Analytic techniques appropriate for ordinally scaled variables are not affected by any monotonic transformation of the numbers assigned to the classes. Such cases can have disproportionately strong effects on statistics. A pattern variable can be used to incorporate interaction in multivariate analysis. An intervally scaled variable whose scores are equal to the product obtained when the values of two other variables are multiplied together. A product variable can be used to incorporate certain types of interaction in multivariate analysis.
Skewness is a measure of lack of symmetry of a distribution.
When used in analysis of variance or covariance, statistical independence between the independent variables is sometimes referred to as a balanced design. Examples include means, variances, correlation coefficients, and many others. Statistical measures are different from statistical tests. Examples include Pearson chi-square, F test, t test, and many others. Statistical tests are different from statistical measures.