Question

Two studies were done on the same set of data, where study I was a one-sided test and study II was a two-sided test. The p-value of the test corresponding to study I was found to be 0.030. What is the p-value for study II?

Answer 1

`0.060`

Explanation:

In a two tailed test the probability of occurrence is the total area under the critical range of values on both the sides of the curve (negative side and positive side)

Thus, the probability values for a two tailed test as compared to a one tailed test is given by the under given relation -

`p-value = P(Z< -(\alpha )/(2) )+P(Z >(\alpha)/(2))`\

Here
`P(\alpha)/(2) = 0.030`

Substituting the given value in above equation, we get -

probability values for a two tailed test

=
`0.030 + 0.030\\= 0.060`