A researcher wants to know if students at UCLA have a similar GPA average as all...
We know that, in the population, the average memory span (number of items a person can recall) is 7, with a standard deviation of 2. We want to know if the herb gingko biloba can really enhance a person’s memory. We get a sample of 25 students and have them take the herb for one month and then test their memory span. What null hypothesis would we test? What is the alternative hypothesis? We know that, in the population, the...
A researcher randomly picked 50 students from a small University and found the followings; Average GPA = 2.8 Variance = 0.04 Given the information above the researcher calculated that 68% of the 50 students have a GPA between ____________ and ___________. 2. Using the information above, if Lisa has a GPA of 3.5, calculate the Z score for Lisa.
34. Use the following information for questions 31-34: The average GPA for all college students in the United States as of 2006 was 3.11. We want to test to see if the GPA of students at Texas A&M is higher than the national average. Suppose we survey 47 randomly selected students at Texas A&M and the average GPA is 3.27, with a standard deviation of 0.54. Assuming all conditions are met, conduct a hypothesis test at the 0.01 significance level. Which of the...
A UCLA researcher claims that the average life span of mice can be extended by as much as 8 months when the calories in their diet are reduced by approximately 40% from the time they are weaned. The restricted diets are enriched to normal levels by vitamins and protein. Suppose that a random sample of 10 mice is fed a normal diet and has an average life span of 32.1 months with a standard deviation of 3.2 months, while a...
32. Use the following information for questions 31-34: The average GPA for all college students in the United States as of 2006 was 3.11. We want to test to see if the GPA of students at Texas A&M is higher than the national average. Suppose we survey 47 randomly selected students at Texas A&M and the average GPA is 3.27, with a standard deviation of 0.54. Assuming all conditions are met, conduct a hypothesis test at the 0.01 significance level. What is the...
A college claims that students in its football program boast an average GPA of 3.0. A sample one year of 110 players reveals an average GPA of 2.86 with a standard deviation of 0.52. We want to test this claim but are only concerned with whether the true GPA of football players is less than 3.0 (if it’s higher, that’s a good thing).
2. A researcher collected data on how much students have paid for their parking at a college campus. The mean of the sample is $54. The researcher wants to test whether the average cost that students have paid is significantly higher than the average cost nationwide, which is $50 per. For a sample of n 9 scores with standard deviation (s) 6, what is the t-statistics? (Show me your work,)
need help with questions 7 and 8 please We wish to know whether the population of ancient Egypt changed considerably in body structure during its existence. 126 skulls found from around 4000 B.C. had an average breadth of 70mm with standard deviation 7.1mm, and 129 skulle found from 200 BC had an average breadth of 84mm with standard deviation 6.7 . What is the most appropriate test for the researcher to use to test the theory that the average breadth...
A college claims that students in its football program boast an average GPA of 3.0. A sample one year of 110 players reveals an average GPA of 2.86 with a standard deviation of 0.52. We want to test this claim, but are only concerned with whether the true GPA of football players is less than 3.0 (if it’s higher, that’s a good thing). (a) What are the null and alternative hypotheses? (b) Calculate the t-value to test the college’s claim....
The average GPA score for students at a university was 3.75. Five years later, a professor wants to perform a hypothesis test to determine whether the average GPA score of students at the university has changed. He picks a random sample of 50 students and obtains their mean GPA score, which is 3.10. The population standard deviation is known as 1.15. Test whether the claim that the average GPA score at the university has dropped from 3.75 is supported or...