Homework 5 For each study, answer each question.
1. Scale of measurement of IV
2. Scale of measurement of DV
(ordinal, nominal, interval, ratio)
A team of cognitive psychologists conducted a study on the effects of sleep deprivation on short-term memory decay. Forty-eight subjects stayed in a lab for two days. Twenty-four of the subjects are randomly assigned to a condition in which they are not permitted to sleep during that period. The other twenty-four are allowed to sleep whenever they want. At the end of the two days, the subjects completea task that involves reading a list of 20words, then recalling as many words as possible.
1) ______________________________________ 2) ______________________________________
Study 2
A researcher examined the effect of different kinds of music on general math ability. Forty-eight subjects were randomly assigned to do series of math tasks under one of three conditions: 16 while listening to soft gentle music, 16 while listening to loud intense music, and 16 while in silence. The math quiz contained arithmetic, geometry, and word problems. There were 25 items that were 2 points each.
1) ______________________________________ 2) ______________________________________
Study 3
A health psychologist conducted a study on the how the number of hours a person exercised
each week relates to the number of days being sick per year. Participants were randomly selected from
the community and provided self-reports through a series of questions on the topics of interest.
1) ______________________________________ 2) ______________________________________
Study 4
A study was designed to test the effects of science fiction movies on participants’ belief in the
supernatural. A scale was designed to measure the degree that a subject believes in the supernatural
on a 1-7 Likert Scale (high scores indicate high levels of belief). Fifty-seven subjects, selected via random
digit dialing (RDD) responded to the scale before and after watching Return of the Jedi, a popular science fiction movie.
1) ______________________________________ 2) ______________________________________
Study 5
A researcher at a drug treatment center wanted to determine the best combination of treatments that would lead to more substance free days. This researcher believed there were two key factors in helping drug addiction: type of treatment and type of counseling. The researcher was interested in either residential or outpatient treatment programs and either cognitive-behavioral, psychodynamic, or client-centered counseling approaches. As new clients enrolled at the center they were randomly assigned to one of six experimental groups. After 3 months of treatment, each client’s symptoms were measured.
1) ______________________________________ 2) ______________________________________
Study 6
An organizational psychologist is hired as a consultant by a person planning to open a coffee house for college students. The coffee house owner wants to know if her customers will drink more coffee depending on the ambience of the coffee house. To test this, the psychologist sets up three similar rooms, each with its own theme (Tropical; Old Library; or New York Café ) then arranges to have thirty students spend an afternoon in each room while being allowed to drink all the coffee they like. (The order in which
they sit in the rooms is counterbalanced.) The amount each participant drinks is recorded for each of the three themes.
1) ______________________________________ 2) ______________________________________
Study 7
A director of a small psychotherapy clinic is trying to plan hiring of temporary staff to assist with intake. She is wondering if there was any difference in the use of the clinic during different seasons of the year. Last year, there were a total of 128 new clients. To see if there is a difference by season she looks at how many clients previously enrolled during each season.
1) ______________________________________ 2) ______________________________________
Study 8
A manager at a retail store in the mall wants to increase profit. The manager wants to see if the store’s layout (one main circular path vs. a grid system of paths) influences how much money is spent depending on whether there is a sale. The belief is that when there is a sale customers like a grid layout, while customers prefer a circular layout when there is no sale. Over two days the manager alternates the store layout, and has the same group of customers come each day. Based on random assignment, half of the customers told there is a sale (20 % will be taken off the final purchases), while the other half is told there is no sale. At the end of each day, the manager calculates the profit.
1) ___________