Q:

# What Does "effect Size" Mean?

A:

In statistics, effect size is the magnitude of the difference between two variables. The most common measures of effect size used are the correlation coefficient "r" and the regression coefficient "R."

## Keep Learning

The correlation coefficient "r" is commonly used in statistics to measure effect size because it can be used to indicate any possible relationship strength between variables. An "r" value of zero indicates that the variables have no relationship at all, while if the absolute value of "r" is 1, the variables are in perfect correlation.

In terms of effect size, if the absolute value of "r" is 0.1, then the variables have a small effect size. If it is 0.3, then the variables have a medium effect size. If it is 0.5, then the variables have a large effect size.

## Related Questions

• A: According to Professor James Jones of Richland Community College, the modal class in statistics, commonly called the mode, is the raw data unit that occurs... Full Answer >
Filed Under:
• A: Physical therapists use math related to ratios, percents, statistics, graphing and problem-solving. Physical therapists need basic problem solving skills, ... Full Answer >
Filed Under:
• A: In statistics, common response refers to changes in both the explanatory and response variables that result from changes in another variable. The variable ... Full Answer >
Filed Under:
• A: The main advantage of statistics is that information is presented in a way that is easy to analyze, which makes its conclusions easily accessible. Comparat... Full Answer >
Filed Under: