In: Statistics and Probability
Decide which inferential method is appropriate to apply for each of the following practical research questions. Write the letter of the appropriate statistical procedure next to each experiment or study question. Each procedure may be used more than once or not at all. Then write an appropriate null and research (alternative) hypothesis for each.
A. Test for µ D. Test for p
B. Test for µd (paired samples) E. Test for p1 - p2
C. Test for µ1 - µ2 (independent samples)
1) Does a new teaching method result in students' post-test scores being higher than their pre-test scores?
2) On average, do college students in the U.S. spend more than $600 per month on
housing?
3) Are men more likely to have a tattoo than women?
4) Did more than 30% of adult Americans gain weight this year?
5) To determine if dentists make people more nervous than a general doctor, the blood pressure of 25 subjects were measured in a dental setting and in an unrelated medical setting.
6) At UWRF is there a difference in the average number of credits a student takes in a semester depending on whether they are from WI or MN?
Answer 1.
Test: Test for µd (paired samples)
Null Hypothesis, Ho: There is no significant difference in the pre-test and post-test scores due to new teaching method i.e. µd = 0
Alternative Hypothesis, Ha: Post Test scores are significantly higher than the pre-test scores due to new teaching method i.e. µd > 0
Answer 2.
Test: Test for µ
Null Hypothesis, Ho: The average monthly spend of US College students on housing is $600 i.e. µ = 600
Alternative Hypothesis, Ha: The average monthly spend of US College students on housing is significantly greater than $600 i.e. µ > 600
Answer 3.
Test: Test for p1 - p2
Null Hypothesis, Ho: There is no significant difference in the proportion of men and women having tattoos i.e. p1-p2 = 0
Alternative Hypothesis, Ha: The proportion of men having tattoos is significantly higher than the proportion of women having tattoos i.e. p1 - p2 > 0
Answer 4.
Test : Test for p
Null Hypothesis, Ho: The Proportions of Americans who gained weight is 0.3 i.e. p = 0.3
Alternative Hypothesis, Ha: The Proportions of Americans who gained weight is significantly greater than 0.3 i.e. p > 0.3
Answer 5.
Test : Test for µd (paired samples)
Null Hypothesis, Ho: There is no significant difference in the average blood pressure when treated when a dentist and a general doctor i.e. µd = 0
Alternative Hypothesis, Ha: The average blood pressure of subjects when treated by a dentist is significantly higher when compared to treated by a general doctor. i.e. µd > 0
Answer 6.
Test: Test for µ1 - µ2 (independent samples)
Null Hypothesis, Ho: There is no significant difference in the average credicts recieved by the students from WI and MN i.e. µ1 - µ2 = 0
Alternative Hypothesis, Ha: There is significant difference in the average credicts recieved by the students from WI and MN i.e. µ1 - µ2 0