Null and research hypotheses: Using the research studies described in the previous exercise, create null hypotheses and research hypotheses appropriate for the chosen statistical test:

A.Taylor and Ste-Marie (2001) studied eating disorders in 41 Canadian female figure skaters. They compared the figure skaters’ data on the Eating Disorder Inventory to the means of known populations, including women with eating disorders. On average, the figure skaters were more similar to the population of women with eating disorders than to those without eating disorders.

B. In an article titled “A Fair and Balanced Look at the News:What Affects Memory for Controversial Arguments,” Wiley (2005) found that people with a high level of previous knowledge about a given controversial topic (e.g., abortion, military intervention) had better average recall for arguments on both sides of that issue than did those with lower levels of knowledge.

C. Engle-Friedman and colleagues (2003) studied the effects of sleep deprivation. Fifty students were assigned to one night of sleep loss (students were required to call the laboratory every half-hour all night) and then one night of no sleep loss (normal sleep). The next day, students were offered a choice of math problems with differing levels of difficulty. Following sleep loss, students tended to choose less challenging problems.

Null and research hypotheses: Using the research studies described in the previous exercise, create null hypotheses and research hypotheses appropriate for the chosen statistical test:

A.Taylor and Ste-Marie (2001) studied eating disorders in 41 Canadian female figure skaters. They compared the figure skaters’ data on the Eating Disorder Inventory to the means of known populations, including women with eating disorders. On average, the figure skaters were more similar to the population of women with eating disorders than to those without eating disorders.

B. In an article titled “A Fair and Balanced Look at the News:What Affects Memory for Controversial Arguments,” Wiley (2005) found that people with a high level of previous knowledge about a given controversial topic (e.g., abortion, military intervention) had better average recall for arguments on both sides of that issue than did those with lower levels of knowledge.

C. Engle-Friedman and colleagues (2003) studied the effects of sleep deprivation. Fifty students were assigned to one night of sleep loss (students were required to call the laboratory every half-hour all night) and then one night of no sleep loss (normal sleep). The next day, students were offered a choice of math problems with differing levels of difficulty. Following sleep loss, students tended to choose less challenging problems.

1. A recent national survey stated 70% of college students said they get less than the recommended amount of sleep every night. A statistician decides to test this claim against the suspicion that the percentage is too high. The statistician randomly sampled 1500 college students from the population of college students and determines that 1020 college students stated they don’t get the recommended amount of sleep. Perform a hypothesis test to answer the question: Do the sample results support the statistician’s claim at

α = 5 %?

1. State the hypotheses (in words & symbols):

H0:

Ha:

2. Determine the model to test H0

Can one use a normal distribution for the Sampling Distribution model to perform this test? Please explain. If not, then what distribution could you use?

b) Using the appropriate notation, state the MEAN & STD ERROR of the sampling distribution: Mean:

STD Error:

3. Determine the Decision Rule:

State the decision rule:

4. Analyze the sample data: Using the appropriate notation, state the sample result of the test, p-value and the test statistic.

sample result (use appropriate notation) is:

p-value ( to 4 decimal places ) is:

test statistic (use appropriate notation) is:   

Hypothesis Testing Model:

5. State the Conclusion:

Do you agree with the statistician suspicion at α = 5%? YOU MUST EXPLAIN YOUR ANSWER OTHERWISE: No credit will be given.

Suppose that during an unexpected snowstorm, Mr. Wong decided to obtain a random sample of students in his AP Statistics class to examine their arrival times. He compared the difference between the students' arrival time with the time the class was supposed to begin.

Mr. Wong asks you (his assistant) to use the information below to answer the following questions (negative value means that the student arrived BEFORE class began).

* Please do not copy other experts’ solution.

Question A: Mr. Wong would like to determine if his students arrive to class late on average. He asks you to perform a hypothesis test @ 10% significance level. Clearly state the conclusion you would tell Mr. Wong using a critical value.

Question B:

i) Mr. Wong asks you to calculate a 90% confidence interval for the average difference in time.

ii) Interpret the interval you calculated.

iii) Based on the interval, what can you say about Mr. Wong's AP Statistics class's arrival time?

Question C: Did you expect the conclusion in Question B to be the same as the conclusion in Question A? Explain why or why not.

I am curious about how many hours per week my students spend on their online coursework. So, I surveyed 9 of my students on how many hours per week they spend on my online PSY 230 course. According to a survey of online college students (in all courses), students studied an average of 9 hours a week for a 3-credit course. I assume that the national study time scores are normally distributed, and I set the significance level at α = .05.

1. Calculate the t statistic for the sample

2. Specify whether the test is a one-tailed or two-tailed test based on the hypotheses form (b), and then determine the critical t value(s) based on the type of test and the preset alpha level

3. Compare the t statistic with the critical t value. Is the calculated t statistic more extreme or less extreme than the critical t value? Then make a decision by stating whether we “reject” or “fail to reject” the null hypothesis

4. Interpret the result in 1-2 sentences (you may restate the hypothesis accepted or explain it in your own words)

5. Calculate the raw effect size and the standardized effect size of this hypothesis test

The Gourmand Cooking School runs short cooking courses at its small campus. Management has identified two cost drivers it uses in its budgeting and performance reports—the number of courses and the total number of students. For example, the school might run two courses in a month and have a total of 60 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,800 per month plus $42 per course plus $5 per student. The company’s sales should average $880 per student.

The company planned to run four courses with a total of 60 students; however, it actually ran four courses with a total of only 56 students. The actual operating results for September appear below:

Required:

1. Prepare the company’s planning budget for September.

2. Prepare the company’s flexible budget for September.

3. Calculate the revenue and spending variances for September.

The Gourmand Cooking School runs short cooking courses at its small campus. Management has identified two cost drivers it uses in its budgeting and performance reports—the number of courses and the total number of students. For example, the school might run two courses in a month and have a total of 60 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,800 per month plus $42 per course plus $5 per student. The company’s sales should average $880 per student.

The company planned to run four courses with a total of 60 students; however, it actually ran four courses with a total of only 56 students. The actual operating results for September appear below:

Required:

1. Prepare the company’s planning budget for September.

2. Prepare the company’s flexible budget for September.

3. Calculate the revenue and spending variances for September.

The Gourmand Cooking School runs short cooking courses at its small campus. Management has identified two cost drivers it uses in its budgeting and performance reports—the number of courses and the total number of students. For example, the school might run two courses in a month and have a total of 64 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,900 per month plus $44 per course plus $5 per student. The company’s sales should average $870 per student.

The company planned to run four courses with a total of 64 students; however, it actually ran four courses with a total of only 56 students. The actual operating results for September appear below:

Required:

Prepare a flexible budget performance report that shows both revenue and spending variances and activity variances for September.

The Gourmand Cooking School runs short cooking courses at its small campus. Management has identified two cost drivers it uses in its budgeting and performance reports—the number of courses and the total number of students. For example, the school might run two courses in a month and have a total of 65 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,800 per month plus $41 per course plus $5 per student. The company’s sales should average $870 per student.

The company planned to run four courses with a total of 65 students; however, it actually ran four courses with a total of only 55 students. The actual operating results for September appear below:

Required:

1. Prepare the company’s planning budget for September.

2. Prepare the company’s flexible budget for September.

3. Calculate the revenue and spending variances for September.