Research question: Amongst Penn State World Campus students, do those who sleep more tend to have higher grade point averages (GPAs)?

Researchers are going to collect data from a sample of 100 Penn State World Campus students. They will call each student to ask how many hours they slept last night and they will ask each student for their GPA (scale of 0 to 4.0).

7. Describe how researchers could use a convenience sampling method to obtain a sample of 100 World Campus students. In other words, describe the procedures of obtaining a convenience sample in this scenario.

8. Describe how researchers could use a simple random sampling method to obtain a sample of 100 World Campus students. In other words, describe the procedures of obtaining a simple random sample in this scenario.

9. In order to obtain a sample that is representative of the intended population, should researchers use the convenience sampling method from question 7 or the simple random sampling method from question 8?

10. Using this scenario, describe an example of response bias. Response bias would occur in this study if… 1

1. Using this scenario, describe an example of non-response bias. Non-response bias would occur in this study if…

12. If a positive relationship is observed between hours of sleep and GPA, can the researchers conclude that sleeping longer causes higher GPAs? Explain why or why not.

13. What is one possible confounding variable in this study? Explain why this is a possible confounding variable.

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 61 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,600 per month plus $46 per course plus $7 per student. The company’s sales should average $890 per student.

The company planned to run four courses with a total of 61 students; however, it actually ran four courses with a total of only 57 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.

Gourmand Cooking School

Planning Budget

For the Month Ended Sept 30

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 $3,900 per month plus $44 per course plus $4 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 59 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. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)

An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?

Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.05α=0.05 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.

1) State the null and alternative hypotheses for the test.

2) Find the value of the standard deviation of the paired differences. Round your answer to three decimal place.

3) Compute the value of the test statistic. Round your answer to three decimal places.

4) Determine the decision rule for rejecting the null hypothesis. Round the numerical portion of your answer to three decimal places.

5) Make the decision for the hypothesis test.

P_1

Which of the following research situations would be most likely to use a between subjects research design?

A. .Examining ethnic differences in reading comprehension among middle school children.

B. Investigating the long-term effectiveness of a stop-smoking treatment by comparing participants
craving for cigarettes after 2 months and 6 months of treatment.

C. Examining academic performance of the Texas State University students by comparing their mean GPA to the national average GPA of undergraduate population in the U.S.

D. All of the above.

P_2

For which of the following situations would a repeated-measures research design be appropriate?

A. Comparing self-esteem for students who participate in school athletics versus those who do not.

B. Comparing mathematical skills of girls versus boys in elementary school age.

C. Comparing patients’ body temperature at the beginning and at the end of medical treatment

D. Comparing verbal skills of science majors versus art majors among undergraduate students

P_3

The t-test for independent sample can be used to examine ____________.

A. The mean difference between two treatment conditions in an experiment (e.g. a difference in performance of experimental group and control group).

B. The mean difference between two populations in quasi-experimental designs (e.g., mean difference in
attitudes to abortion between residents of the southern vs. northern states in the U.S.).

C. The mean difference in stress level at the beginning and the end of semester in a sample of undergraduate students.

D. A & B

E. All of the above.

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 $4,000 per month plus $45 per course plus $4 per student. The company’s sales should average $890 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 50 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. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)

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 62 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,500 per month plus $44 per course plus $3 per student. The company’s sales should average $890 per student.

The company planned to run four courses with a total of 62 students; however, it actually ran four courses with a total of only 58 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. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)

Based on previous research and sound theoretical considerations, an experimental psychologist believes that memory for pictures is superior to memory for words. To test this hypothesis, the psychologist performs an experiment in which students from a introductory psychology class are used as subjects. Eight randomly selected students view 30 slides with nouns printed on them, and another group of eight randomly selected students view 30 slides with actual pictures of the same nouns. Each slide contains either one noun or one picture and is viewed for 4 seconds. After viewing the slides, students are given a recall test. The number of correctly recalled items is recorded. The data collected are given below.

# of pictures recalled: 18 21 14 25 23 19 26 15

# of nouns recalled: 12 9 21 17 16 10 19 22

a. Describe (1) the independent variable and its levels, and (2) the dependent variable and its scale of measurement.

b. Describe the null and alternative hypotheses for the study described.

c. Using Excel, conduct a statistical test of the null hypothesis at p = .05. Be sure to properly state your statistical conclusion.

d. Provide an interpretation of your statistical conclusion in part C.

e. What type of statistical error might you have made in part C?

f. Obtain the 95% confidence interval using the obtained statistic.

g. Provide an interpretation of the confidence interval obtained in part f.

h. Does the confidence interval obtained support your statistical conclusion? Explain your answer.

A study was designed to compare the attitudes of two groups of nursing students towards computers. Group 1 had previously taken a statistical methods course that involved significant computer interaction. Group 2 had taken a statistic methods course that did not use computers. The students' attitudes were measured by administering the Computer Anxiety Rating Scale (CARS). A random sample of 16 16 nursing students from Group 1 resulted in a mean score of 55.4 55.4 with a standard deviation of 4.5 4.5 . A random sample of 8 8 nursing students from Group 2 resulted in a mean score of 66 66 with a standard deviation of 8.3 8.3 . Can you conclude that the mean score for Group 1 is significantly lower than the mean score for Group 2? Let μ1 μ 1 represent the mean score for Group 1 and μ2 μ 2 represent the mean score for Group 2. Use a significance level of α=0.05 α = 0.05 for the test. Assume that the population variances are equal and that the two populations are normally distributed.

Step 1 of 4 : State the null and alternative hypotheses for the test. Step 2 of 4: Compute the value of the t test statistic. Round your answer to three decimal places. Step 3 of 4: Determine the decision rule for rejecting the null hypothesis H0. Round your answer to three decimal places. Step 4 of 4: State the test's conclusion.

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 63 students enrolled in those two courses. Data concerning the company’s cost formulas appear below:

For example, administrative expenses should be $3,600 per month plus $40 per course plus $3 per student. The company’s sales should average $880 per student.

The company planned to run four courses with a total of 63 students; however, it actually ran four courses with a total of only 59 students. The actual operating results for September were as follows:

Required:

Prepare a flexible budget performance report that shows both revenue and spending variances and activity variances for September. (Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)