Confidence Interval Formula T Test. The formula for the confidence interval for one population mean using the t distribution is. We now put everything together and see that our margin of error is 2 09 x 1 2583 which is approximately 2 63.
T x μ s n t 74 78 3 5 10 t 3 61. ˉx tn 1 α 2 s n ˉx tn 1 1 α 2 s n. The significance level is equal to 1 confidence level.
Then the proof is a bit on the trivial side because we then know that.
In this case the sample mean is 4 8. So a significance level of 0 05 is equal to a 95 confidence level. T confidence interval formula confidence t alpha standard dev size the function uses the following arguments. Therefore the absolute t test value of the sample is 3 61 which is less than the critical value 3 69 at 99 5 confidence interval with a degree of freedom of 9.
