Paired T Test Confidence Interval Formula. Thus 90 confidence interval estimate for mean of the difference is 2 123 3 877. The paired t test statistics value can be calculated using the following formula.
N is the sample size i e size of d. T frac m s sqrt n where m is the mean differences. From the table of t scores see other resource on the right t 2 145.
We now put everything together and see that our margin of error is 2 09 x 1 2583 which is approximately 2 63.
From the mean paired difference to the confidence limits will be less than or equal to the value specified. The formula of the paired t test is defined as the sum of the differences of each pair divided by the square root of n times the sum of the differences squared minus the sum of the squared differences overall n 1. Confidence interval for a mean with paired data. The formula for the paired t test is given by t frac sum d sqrt frac n sum d 2 sum d 2 n 1 where σd is the sum of the differences.
