P-Value Find the P-value in a test of the claim that the mean annual income of a CIA agent is greater than $81,623 (based on data from payscale.com) given that the test statistic is t = 1.304 for a sample of 40 CIA agents.

Short Answer

Expert verified

The p-value is equal to 0.10.

Step by step solution

01

Given information

It is claimed that the mean annual income of a CIA agent is greater than $81,623. A sample of 40 agents is considered. The test statistic value obtained is equal to t=1.304.

02

P-value

The claim contains a greater than sign. Thus, the test will be right-tailed.

The degrees of freedom are computed below:

\(\begin{array}{c}df = n - 1\\ = 40 - 1\\ = 39\end{array}\)

The p-value corresponding to the t-score of 1.304 can be noted from the Student’s t distribution table for a two-tailed test with 39 degrees of freedom.

Here, the p-value is approximately equal to 0.10.

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