1. Eighteen SJSU students were surveyed about their opinions on two teaching evaluations: ratemyprofessor.com and SOTES (Student Opinion of Teaching Effectiveness). They indicated the level of effectiveness on a 7-point scale, with “1” being “not very effective” and “7” being “very effective”. The rating scores are shown below by teaching evaluation.
Observation SOTES ratemyprofessor.com
1 4 7
2 6 6
3 5 4
4 6 5
5 7 3
6 5 4
7 7 6
8 4 2
A) Which teaching evaluation is more effective? Show all the calculations (1 pt).
B) Students have more different or diverse opinions on which teaching evaluation? Use all the observations and show all the calculations (3 pts).
2. Ms. Green is responsible for recruiting international students for a summer internship at her company. Her recruiting job is almost done, but she needs to pick one last student from three candidates. They are all very competitive and it seems that the only way to rank them is their college GPAs. Ming is from China and his score is 91.8 out of 100. Leif is from Norway and his score is 4.21 out of 5. Jason is from the U.S. and his score is 3.55 out of 4. Luckily, Ms. Green also has the mean and standard deviation of college GPAs from each country (see table). If you were Ms. Green, which candidate will you choose for the summer internship? Show all the calculations (2 pts).
Country Mean SD Candidate’s Score
China 82.7 8.9 91.8 (Ming)
Norway 2.46 1.63 4.21 (Leif)
US 2.24 1.29 3.55 (Jason)
3.Suppose a fast-food restaurant wishes to estimate average sales volume for a new menu item. The restaurant has analyzed the sales of the item at a similar outlet and observed the following results:
X = 715 (mean daily sales)
S = 114 (standard deviation of sample)
n = 36 (sample size)
The restaurant manager wants to know into what range the mean daily sales should fall 95 percent of the time. Perform this calculation (2 pts).
4. A group of marketing researchers study the expenditure on dinning out. They want to have a 95 percent confident level (Z) and accept a magnitude of error (E) of less than $2.75. The estimate of the standard deviation is $15.80 based on their pilot study. What is the calculated sample size if they want to run a survey? Perform this calculation (2 pts)