Download Lab 1 - Professor Mo Geraghty

Math 10 Summer - Lab 1 – Creating Dot Plots and Descriptive Statistics from Data
Open MINITAB file rateMP.mpj from the website. This data represents information 700 instructors from
the popular website ratemyprofessors.com. All instructors are sampled from the Foothill-De Anza
Community College District. Here is a description of the data:
College:
Smiley:
Photo:
Hot:
Gender:
Dept:
Division
Num
Overall
Easiness
Foothill or De Anza
Positive
Neutral
Negative
Instructor has a photo
Instructor has a chili pepper
Male or Female
Academic Department (example - Mathematics)
Academic Division (example - PSME)
Number of Ratings for that faculty member
Average Overall Quality Rating (1-5 scale, lowest to highest)
Average Easiness Rating (1-5 scale, hardest to easiest)
We are going to use Minitab to make some dot plots for this data. Specifically we are going to look at
Average Overall Quality Rating and try to make some comparisons of groups. First, let's ask some
questions about this data.
1. Identify the quantitative variables.
2. Identify the categorical variables.
3. Is this an observational study or an experiment? Explain.
4. What is the population?
5. What is the sample?
6. Do you think this is a fair sample of instructors? Explain.
Now we are going to make some dot
plots of the Average Overall Quality
Rating which can be found under the
GRAPHS menu command in
MINTAB
7. Make a dot plot of all instructors' Average Overall Quality Rating. (Simple Dot Plot). Paste the
graph here and analyze the dot plot. (You may describe the data's shape, center and spread)
8. Make a dot plot of all instructors' Average Overall Quality Rating by gender. (With Groups Dot
Plot). Paste the graph here. Do you see any difference in overall quality between males and
females?
9. Make a dot plot of all instructors' Average Overall Quality Rating by college. (With Groups Dot
Plot). Paste the graph here. Do you see any difference in overall quality between Foothill and De
Anza instructors?
10. Make a dot plot of all instructors' Average Overall Quality Rating by hotness. (With Groups Dot
Plot). Paste the graph here. Do you see any difference in overall quality between "Hot""and "Not
Hot" instructors?
11. Write a paragraph summarizing your results. Do you see any problems or bias with this study?
In the first questions, we made some dot plots
and made some interpretations of Average
Overall Quality Rating. In this part, we will look
at other graphs and statistics that measure
center, spread and relative standing.
12. Above is a dot plot you made of Average Overall Quality Rating in the first part of this lab. Make a
histogram of the Average Overall Quality Rating. Paste the graph here. Are both graphs showing
the same center, spread and shape? Explain your answer.
Descriptive Statistics can be found in
Minitab under STAT>BASIC STATISTICS.
13. Use this command to determine the sample mean and sample median for the Average Overall
Quality Rating. Paste the results here and answer these questions:
a. Which statistic is a better measure of center for this data? Explain your answer.
b. Are the values of the sample mean and median consistent with the shape of the histogram?
Explain your answer.
Here are dot plots comparing Average Overall
Quality Ratings of instructors who are rated
"hot" vs. those who are rated "not hot" that you
made earlier in this lab.
14. Under the GRAPHS menu bar in Minitab, create box plots of Average Overall Quality Ratings
comparing "hot" and "not hot" instructors. Paste the results here and from the box plots, answer
these questions.
a. Which group has a higher sample median?
b. For the "hot" instructors, between what values would you find the middle 50% of ratings?
c. For the "not hot" instructors, between what values would you find the middle 50% of
ratings?
d. Are there any possible outliers for the "hot" instructors? Explain.
15. Under the STAT>BASIC STATISTICS menu, find descriptive statistics for both "hot" and "not hot"
instructors. Paste the results here.
a. Which group has a higher sample mean? Is this result consistent with your box plot?
b. Which group has a higher sample standard deviation? Is this result consistent with your
box plot?
c. What is more unusual: A "hot" instructor with an Overall Rating of 3.5 or a "not hot"
instructor with an Overall Rating of 3.5? Calculate and compare the Z-scores for each
instructor to answer this question.
d. Using the Empirical Rule, between what two Average Overall Quality Ratings would you
find 68% of the "not hot" instructors?
Email this word file as an attachment to your instructor [email protected].