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Chapter 8: Q9E (page 452)

Question: Independent random samples n1 =233 and n2=312 are selected from two populations and used to test the hypothesis Ha:(μ1-μ)2=0against the alternative Ha:(μ1-μ)2≠0

.a. The two-tailed p-value of the test is 0.1150 . Interpret this result.b. If the alternative hypothesis had been Ha:(μ1-μ)2<0 , how would the p-value change? Interpret the p-value for this one-tailed test.

Short Answer

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Answer

Random sampling guarantees that the findings received from your sample are close to those received if the full sample was surveyed.

Step by step solution

01

(a) Interpret the result for the given two-tailed p-value of the test

The null hypothesis is Ha:μ1-μ2=0

If we take the significance level to be 0.05 and the p-value is 0.1150.

As the p-value is more than the significance level, so the null hypothesis will not be rejected.

If we take the significance level to be 0.01 , and the p-value is 0.1150 .

As the p-value is more than the significance level, so the null hypothesis will not be rejected.

02

(b) Interpret the p-valueHa:(μ1-μ)2<0  .

If the alternative hypothesis has changed from Ha:μ1-μ2≠0toHa:μ1-μ2<0 , it implies that the p-value should be halved as now it is a one-tailed test instead of a two-tailed test.

So, the p-value will be 0.0575 .

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Most popular questions from this chapter

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