How to statistically see if there is a correlation

Question

Hi,

 

Ive got 2 sets of data. 181 figures in each. Can I use Pearson's Corrrelation Coefficient to see if there is a correlation between them. And if so what would this mean r = -0.28, p = 0.00001 P-value < 0.05

Answer 1

Yes. Pearson's correlation coefficient measures the strength of a linear relationship between the two data sets.

 

A value of 0 indicates no relationship. A value greater than 0 indicates a positive relationship, and less than zero indicates an inverse relationship. A value of 1 indicates an exact relationship.

 

If you say there are three categories of strength: low, medium and high, you might estimate them as:

 

Low: 0.1 to 0.3 (-0.1 to -0.3)

 

Medium: 0.3 to 0.5 (-0.3 to -0.5)

 

High: 0.5 to 1.0  (-0.5 to -1.0)

 

In your data, there is some small inverse relationship between the data sets.