Correlation Coefficient Graphs and r values, Correlation coefficient

What does the r-value tell us?

A number between -1 and 1 which tells us the strength(weak, moderate, strong) and direction (positive or negative) of a correlation.

Define no relationship between X and y:

If there is no linear correlation or a weak linear correlation, r isclose to 0. A value near zero means that there is a random, nonlinear relationship between the two variables

Describe the association of a scatter plot with an r value of -0.1

The correlation would be a very weak negative.

Describe the association of a scatter plot with an r value of -0.45

The correlation would be moderately negative.

Describe the relationship of a scatter plot with an r value of 0.6

The correlation would be moderately positive

Correlation coefficient

a measure of the linear correlation between two variables X and Y, giving a value between +1 and −1. The number will tell you the strength and direction of the scatter plot.

Define a strong Positive correlation:

r is close to +1. As values for x increases, values for y also increase.

Define a strong Negative correlation:

r is close to -1. As values for x increase, values for y decrease.