pearsons r : An r value obtained through a correlation.

A Pearson's r is a number that represents the strength of a correlation. It can be between -1 and 1. Values of zero or very close to zero mean that there is no detectable correlation. Values close to 1 mean that there is a very strong positive correlation. Values close to -1 mean that there is a very strong negative correlation.

A positive correlation is a situation where two variables tend to rise and fall together. Height and weight are positively correlated. As a general rule, it is true that larger height tends to occur with larger weight.