Intro to Statistics for the Social Sciences
Spring, 2015, Dr. Suzanne Delaney
Homework #9
Lab Session: _____
CID Number: _________
Name: _____________________________
Donald has been given a set of analyses to perform. He knows that there are five types of analyses available
to him: correlation, t-tests, one-way ANOVA, two-way ANOVA and confidence intervals. Please help him
identify which analysis goes with each situation presented. (You may want to use pencil.)
This worksheet is designed to provide you with opportunities to

Review characteristics of data (levels of measurement)

Review design characteristics in simple studies

Review the logic of hypothesis testing

Create the most appropriate graph
1. You belong to a student group that is trying to raise money for a local charity that
you feel passionately about. So, you organize the group to sell peanuts at the
university football games. You want to know whether class standing (i.e. freshman,
sophomore, junior, or senior) will make a difference in the number of peanuts sold. You
are looking to see if “class standing” affects the “level of sales”. So, for each student
selling peanuts you measure how many peanuts they sold, then you found an average
for each group of students. You found that freshman on average sold 100 bags of
peanuts, sophomores sold on average150 bags of peanuts, juniors sold on average
150 bags of peanuts, and seniors sold on average 100 bags of peanuts. Please
complete this graph and provide the following information:
 Independent variable (IV):________________
 Number of levels of IV: __________________
 Level of measurement of IV: _____________
 Quasi or True experiment:________________
 Dependent variable (DV): ____________________
 Level of measurement of DV: _____________
 Between or within participant design: _____________
 Analysis that is most appropriate: _________________
correlation, t-tests, one-way ANOVA, two-way ANOVA or confidence intervals.

Donald found that the difference between the groups was
statistically significant.
o Should he reject the null hypothesis? yes no
o Should he report the p < 0.05? yes no
2. Your fundraiser was a great success (congratulations!). You repeated it over several games and for
every game, lots of peanuts were sold and your group made a lot of money for your charity. Another
student group wants to know if they would have the same success if they tried the same idea. You tell
them that it is hard to say because it depends on so many things. But they really want your best guess at
how many peanuts each student will sell on average. (They want you to guess at the mean number of
peanuts that will be sold per student seller). So, you simply calculate the average number of bags of
peanuts sold by each student for all of the football games. It turns out that the average is 125 bags of
peanuts per student. You told them that your best guess was that each person will probably sell about 125
bags of peanuts. This is your “point estimate” of how many bags each student will sell (this is just a simple
average from your student sellers). But they want a (95%) range of the fewest
bags they are likely to sell (per student seller) and the most bags they are likely
to sell. Please complete this graph and provide the following information:
 Describe your variable:___________________________________
 Dependent variable: _frequency____________________________
 Analysis that is most appropriate: _________________
correlation, t-tests, one-way ANOVA, two-way ANOVA or confidence intervals.
3. You work for a small company that has recently designed a new program to treat obesity, and you want to
know if it works. You enroll 100 people who weigh more than 50 pounds more than their ideal weight. You
randomly assign half of the people to participate in the program and half to diet however they choose. You
are looking to see whether the type of diet has an effect on weight loss. You found that people who ate
their regular diet lost 10 pounds, while people on the new program lost 20 pounds. Please complete this
graph and provide the following information:
 Independent variable (IV):_______________________
 Number of levels of IV: _________________________
 Level of measurement of IV: _____________
 Quasi or True experiment:_______________________
 Dependent variable: ___________________________
 Level of measurement of DV: _____________
 Between or within participant design: ______________
 Analysis that is most appropriate: ___________________
correlation, t-tests, one-way ANOVA, two-way ANOVA or confidence intervals.

Donald found that the difference between the groups was statistically significant.
o Should he reject the null hypothesis? yes no
o Should he report the p < 0.05? yes no
4. You work for a small company that has recently designed a new program to treat obesity, and you want
to know if it works and if it works differently for men and women. You enroll 100 people who weigh more
than 50 pounds more than their ideal weight. You randomly assign half of the people to participate in the
program and half to diet however they choose. You are looking to see whether the type of diet has an
effect on weight loss. You found that women who ate their regular diet lost 5 pounds, and men lost 15,
while women on the new program lost 15 pounds and men lost 25 pounds.
Please complete this graph and provide the following information:
 Independent variable 1 (IV):_______________________
 Number of levels of IV1: _________________________
 Independent variable 2 (IV):_______________________
 Number of levels of IV2: _________________________
 Quasi or True experiment (or mixed):_______________________
 Dependent variable: ___________________________
 Between or within participant design: ______________
 Analysis that is most appropriate: ___________________
correlation, t-tests, one-way ANOVA, two-way ANOVA or confidence intervals.
5. You’ve been hired by a limousine service in Pasadena, California to figure
out the most efficient routes for their most highly travelled destinations in and
around Los Angeles. The company employs 30 drivers. The drivers disagree on
which routes are better some say that the most direct route is fastest (even though
traffic can be heavy and can increase driving time). You have been asked to
evaluate the relationship between driving time and distance. Please complete this
graph and provide the following information:
 Dependent variable 1:________________
 Dependent variable 2: ________________
 Estimate of the direction and strength of the relationship: __________
 Analysis that is most appropriate: ___________________
correlation, t-tests, one-way ANOVA, two-way ANOVA or confidence intervals.

Donald found that the relationship was statistically significant.
o Should he reject the null hypothesis? yes no
o Should he report the p < 0.05? yes no
d15s_sbs200_hw9_hypoth_prototypical_designs.docx