# How do you construct confidence interval for a correlation coefficient?

Feb 13, 2016

Population Correlation coefficient = Sample correlation coefficient $\pm$[Critical value $\times$ Standard Error ]

#### Explanation:

Population Correlation coefficient = Sample correlation coefficient $\pm$[Critical value $\times$ Standard Error ]

Critical value is the table value.

If the sample size is greater than 30, you have to refer Normal Distribution . Its value depends on the confidence level.

Say for example if the confidence level is 99% the critical value is $2.58$

If the sample size is less than 30, you have to refer $t$ Distribution Table.

The value depends on confidence level and the degrees of freedom.