A random sample of 100 observations from a population with s
A random sample of 100 observations from a population with standard deviation 14.05 yielded a sample mean of 92.4. 1. Given that the null hypothesis is =90 and the alternative hypothesis is >90 using =.05, find the following:
(a) Test statistic = 1.708185053
(b) P - value:
(c) The conclusion for this test is: A. Reject the null hypothesis B. There is insufficient evidence to reject the null hypothesis C. None of the above
2. Given that the null hypothesis is =90 and the alternative hypothesis is 90 using =.05, find the following:
(a) Test statistic = 1.708185053
(b) P - value:
(c) The conclusion for this test is: A. There is insufficient evidence to reject the null hypothesis B. Reject the null hypothesis C. None of the above
HOW DO YOU FIND P??
Solution
1)
to find p value for this problem we need to use tables of Z distribution because we know the value
of Sigma of the population
so using Z distribution
we have the value of test statistics that is our Z = 1.71 aprox. 2 decimals
using tables of Z distribution we need to find a probability for Z = 1.71
so P value is 0.0436
The conclusion for this test is
Reject the null hypothesis
Why? because our P value is less than alpha
if P value was greater than alpha then we fail to reject the null hypothesis
but yfor this case we reject the null hypothesis
2)
to find this p value is the same as we do in the first question but something will change because the alternative hypothesis is different
when the sign is not equal to, that means that can be less than or greater than, we are talking about a 2 tailed test
that means that the decision rule will be
alpha/2 = 0.025
if P value is greater than 0.025 then , we fail to reject Ho
if P value is less than 0.025 then, we reject Ho
Pvalue is the same because Z = 1.71
P value = 0.0436
since P value is greater than 0.025 we fail to reject Ho
that means There is insufficient evidence to reject the null hypothesis
