reciprocality, reciprocity - a relation of mutual dependence or action or influence

statistics - a branch of applied mathematics concerned with the collection and interpretation of quantitative data and the use of probability theory to estimate population parameters

parametric statistic - any statistic computed by procedures that assume the data were drawn from a particular distribution

Pearson product-moment correlation coefficient, product-moment correlation coefficient - the most commonly used method of computing a correlation coefficient between variables that are linearly related

multiple correlation coefficient - an estimate of the combined influence of two or more variables on the observed (dependent) variable

biserial correlation, biserial correlation coefficient - a correlation coefficient in which one variable is many-valued and the other is dichotomous

chance-half correlation, split-half correlation - a correlation coefficient calculated between scores on two halves of a test; taken as an indication of the reliability of the test

tetrachoric correlation, tetrachoric correlation coefficient - a correlation coefficient computed for two normally distributed variables that are both expressed as a dichotomy

statistics - a branch of applied mathematics concerned with the collection and interpretation of quantitative data and the use of probability theory to estimate population parameters

correlational analysis - the use of statistical correlation to evaluate the strength of the relations between variables

curvilinear correlation, nonlinear correlation, skew correlation - any correlation in which the rates of change of the variables is not constant

partial correlation - a correlation between two variables when the effects of one or more related variables are removed

direct correlation, positive correlation - a correlation in which large values of one variable are associated with large values of the other and small with small; the correlation coefficient is between 0 and +1

indirect correlation, negative correlation - a correlation in which large values of one variable are associated with small values of the other; the correlation coefficient is between 0 and -1

spurious correlation - a correlation between two variables (e.g., between the number of electric motors in the home and grades at school) that does not result from any direct relation between them (buying electric motors will not raise grades) but from their relation to other variables