Question

Refer to the TI output below. What is the correct conclusion? Totest t=5.422176685 p=4.4974012E-5 Sx=5 n=15 We do not have evidence that the population mean is more than 75. We do not have evidence that the population mean is 82 We have evidence that the sample mean is more than 75. We have evidence that the population mean is more than 75 Correct answer is not given.

Answer 1

Answer:

For first question, the hypothesis will be:

H0 : $\mu$ = 0 verses H1: $\mu$ > 0

The decision criteria:

We reject H0 if p-value is less than given level of significance.

Here level of significance is not given, consider it as 0.05.

Now P-value = 4.4974012E-5 = 0.00004497 , which is less than 0.05. Hence we reject H0. H1 can be accpted.

$\mu$ is population mean.

Hence, correct option is:

We have evidence that population mean is more than 75.

Q13.

We know for indepedent sample t test, hypothesis is :

H0: $\mu_1 =\mu_2$ verses H1: $\mu_1 \neq\mu_2$ ( significant).

i.e. H0: $\mu_1 -\mu_2=0$

That means if $\mu_1 -\mu_2$ = 0 is included in confidence interval, then it is not significant.

Here given confidence interval is ( -21.17 , 81.168 ). In this confidence interval 0 is included in it .

Hence correct option is :

The population means of two groups are not significantly different.