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1. A statistical relation between two or more variables such that systematic changes in the value of one variable are accompanied by systematic changes in the other
   - correlational statistics
    
2. (statistics) a statistic representing how closely two variables co-vary; it can vary from -1 (perfect negative correlation) through 0 (no correlation) to +1 (perfect positive correlation)
   "what is the correlation between those two variables?";
   - correlation coefficient, coefficient of correlation

Derived forms: correlations

Type of: parametric statistic, statistics, stats [informal]

Part of: correlational analysis

Encyclopedia: Correlation, not causation