Correlation Coefficient

Front

What is the correlation coefficient?

Back

A statistical measure that describes the strength and direction of a relationship between two variables, ranging from -1 to 1.

Front

What does a correlation coefficient of r=1 indicate?

Back

A perfect positive correlation, meaning as one variable increases, the other variable also increases.

Front

What does a correlation coefficient of r=-1 indicate?

Back

A perfect negative correlation, meaning as one variable increases, the other variable decreases.

Front

What does a correlation coefficient of r=0 indicate?

Back

No correlation, meaning there is no linear relationship between the two variables.

Front

What is a strong positive correlation?

Back

A relationship where increases in one variable are associated with increases in another variable, typically indicated by a correlation coefficient close to 1.

Front

What is a strong negative correlation?

Back

A relationship where increases in one variable are associated with decreases in another variable, typically indicated by a correlation coefficient close to -1.

Front

What is a weak positive correlation?

Back

A relationship where increases in one variable are associated with increases in another variable, but the relationship is not strong, indicated by a correlation coefficient closer to 0 than to 1.

Front

What is a weak negative correlation?

Back

A relationship where increases in one variable are associated with decreases in another variable, but the relationship is not strong, indicated by a correlation coefficient closer to 0 than to -1.

Front

How can you visually assess correlation in a scatter plot?

Back

By observing the direction and tightness of the points; a clear upward trend indicates positive correlation, a downward trend indicates negative correlation, and a random scatter indicates no correlation.

Front

What is the formula for calculating the correlation coefficient (r)?

Back

r = (nΣxy - ΣxΣy) / sqrt[(nΣx^2 - (Σx)^2)(nΣy^2 - (Σy)^2)] where n is the number of pairs.