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Hypothesis Testing: One-Tailed Two Independent Means

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Wize University Statistics Textbook > Inference for Two Population Means

Hypothesis Testing for Two Independent Means

2 Activities

We wish to test the hypothesis that people exercising regularly sleep more on average than those that don't exercise at all. Here is data on a group of individuals for both groups. The number of hours of sleep for each person is recorded.

Let μ1\mu_1 represent the mean hours of sleep for people that exercise regularly.
Let μ2\mu_2 represent the mean hours of sleep for people that don't exercise.

a) Find the standard error of x‾1−x‾2\overline{x}_1-\overline{x}_2

b) At the 5% level of significance, is there evidence to suggest that exercising leads to more sleep?





a) Find the standard error of x‾1−x‾2\overline{x}_1-\overline{x}_2
More Hypothesis Testing for Two Independent Means Questions:
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You wish to test Ho:μA−μB=0   Ha:μA−μB≠0H_o:\mu_A-\mu_B=0\ \ \ H_a:\mu_A-\mu_B\ne0
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Hypothesis Testing: One-Tailed Two Independent Means
We wish to test the hypothesis that people exercising regularly sleep more on average than those that don't exercise at all. Here is data on a group of individuals for both groups. The number of hours of sleep for each person is recorded.
Let μ1\mu_1 represent the mean hours of sleep for people that exercise regularly.
Let μ2\mu_2 represent the mean hours of sleep for people that don't exercise.
Hypothesis testing for two independent means
Red Fish and Blue Fish are randomly sampled. Is there evidence that mercury levels are higher in Blue Fish than Red Fish? Assume unequal variances. Summary:
It was assumed that the variances of the populations were different (even though the sample standard deviations suggest otherwise!). What is the conclusion at the 1% level of significance?
Hypothesis Testing for Two Independent Means
Statistics KANATA reports that on average males earn more than females when controlling for job occupation and other factors such as level of experience. You collect a random sample of 10 males and 9 females in Canada and record the following data:
In addition, statistics KANATA reports that since 1900 the standard deviations of the earnings are roughly equal.
a) At the 5% level of significance, what is your conclusion based on the data you collected when you test the reported numbers by Stats KANATA.
Hypothesis Testing for Two Independent Means
We wish to test the hypothesis that people exercising regularly sleep more on average than those that don't exercise at all. Here is data on a group of individuals for both groups. The number of hours of sleep for each person is recorded. Assume the population standard deviations are different.
Let μ1\mu_1 represent the mean hours of sleep for people that exercise regularly.
Let μ2\mu_2 represent the mean hours of sleep for people that don't exercise.
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