An field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at = 0.10, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree?
A) The data does not support the conclusion that the average pine tree trunks are larger because the test value 0.53 is less than than the critical value1.28.
B) The data does not support the conclusion that the average pine tree trunks are larger because the test value 1.03 is less than than the critical value 1.28.
C) The data does not support the conclusion that the average pine tree trunks are larger because the test value 1.03 is less than than the critical value 1.65.
D) The data does not support the conclusion that the average pine tree trunks are larger because the test value 23.05 is greater than than the critical value 1.65.

Question

An field researcher is gathering data on the trunk diameters of mature pine and spruce trees in a certain area. The following are the results of his random sampling. Can he conclude, at  = 0.10, that the average trunk diameter of a pine tree is greater than the average diameter of a spruce tree? 
A) The data does not support the conclusion that the average pine tree trunks are larger because the test value 0.53 is less than than the critical value1.28. 
B) The data does not support the conclusion that the average pine tree trunks are larger because the test value 1.03 is less than than the critical value 1.28. 
C) The data does not support the conclusion that the average pine tree trunks are larger because the test value 1.03 is less than than the critical value 1.65. 
D) The data does not support the conclusion that the average pine tree trunks are larger because the test value 23.05 is greater than than the critical value 1.65.

Quizplus · Accepted Answer

The null hypothesis is that the average diameter of a pine tree is equal to the average diameter of a spruce tree. The alternative hypothesis is that the average diameter of a pine tree is greater than the average diameter of a spruce tree. The researcher conducted a one-sample t-test with a significance level of 0.10. The test statistic is 1.03, which is less than the critical value of 1.28 for a one-tailed test with 38 degrees of freedom. Therefore, the researcher cannot conclude that the average diameter of a pine tree is greater than the average diameter of a spruce tree at the 0.10 significance level.

An Field Researcher Is Gathering Data on the Trunk Diameters