Question

In: Statistics and Probability

Researchers interested in the trees of a forest in Vermont selected a random sample of 8...

Researchers interested in the trees of a forest in Vermont selected a random sample of 8 red oak trees and measured various characteristics of these trees. Here are the heights of the trees, in feet: 32, 48, 35, 51, 46, 30, 28, 39 In a study done several years earlier the average height of red oak trees in this forest was reported to be 35 feet. The researchers claim that the average height is now greater than 35 feet. Test the researchers claim by performing a StatKey randomization test using the sample data. What is the P-value of the test?

Group of answer choices:

about 0.1%

about 21%

about 11%

about 3%

Solutions

Expert Solution

null hypothesis: Ho:             μ = 35
Alternate Hypothesis: Ha:μ 35
0.05 level with right tailed test and n-1= 7 df, critical t= 1.8946
Decision rule :                   reject Ho if test statistic t>1.895
population mean μ= 35
sample mean         x= 38.625
sample size             n= 8
sample std deviation s= 8.782
std error sx=s/√n= 3.1049
test stat t='(x-μ)*√n/s=   1.1675
p value                                 = 0.1406

about 11 %


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