6. Glossary

Correlation; Correlation

The relationship between two observables, one of which implies the other and vice versa. A linear correlation is graphically expressed by a straight line.

Correlation coefficient ;

Index that expresses the degree of linkage of given variables; it varies between –1 and + 1.

Distribution curve; Curve distribution

Curve representing the distribution function, or cumulative distribution function, of a real random variable X is the function F which, for any real x, associates the probability of obtaining a value less than or equal to :