SOLUTION: Determine whether a correlation coefficient of r = -0.405 is significant at 5% level for a sample size of 22. r is not sifnificant at 5% or r is significant at 5%

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Question 380865: Determine whether a correlation coefficient of r = -0.405 is significant at 5% level for a sample size of 22. r is not sifnificant at 5% or r is significant at 5%
Answer by robertb(5830) About Me  (Show Source):
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Use the t-distribution for small samples.
The test statistic is t+=+r%2Asqrt%28%28n-2%29%2F%281-r%5E2%29%29. Then t+=+r%2Asqrt%2820%2F%281-%28-0.405%29%5E2%29%29+=+-1.98.
Degree of freedom is 22- 2 = 20.
For 20 df and one-tailed test, critical value is -1.725. Since -1.725 > -1.98, r is significant at the 5% level.