Introduction To Statistics And Data Analysis
6th Edition
ISBN: 9781337793612
Author: PECK, Roxy.
Publisher: Cengage Learning,
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Textbook Question
Chapter 2.3, Problem 47E
The paper “Turning to Learn: Screen Orientation and Reasoning from Small Devices” (Computers in Human Behavior [2011]: 793–797) describes a study that investigated whether cell phones with small screens are useful for gathering information. The researchers wondered if the ability to reason using information read on a small screen was affected by the screen orientation. The researchers assigned 33 undergraduate students who were enrolled in a psychology course at a large public university to one of two groups at random.
One group read material that was displayed on a small screen in portrait orientation, and the other group read material on the same size screen but turned to display the information in landscape orientation (see figure below).
The researchers found that performance on a reasoning test that was based on the displayed material was better for the group that read material in the landscape orientation.
- a. Is the described study an observational study or an experiment?
- b. Did the study use random selection from some population?
- c. Did the study use random assignment to experimental groups?
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Can the introduction of pleasant sensory stimuli lead to a more pleasant exercise environment and decrease perceived exertion during a four‑minute stepping task? Forty‑three students from a Southeastern University were assigned at random to three conditions: "taste," in which participants inserted a lemon‑flavored mouth guard during the task; "placebo," in which participants inserted a non‑flavored mouth guard; and "control," in which no mouth guard was used. Twelve students were assigned to the taste group, 15 to the placebo group, and 16 to the control group. Ratings of perceived exertion (RPE) scores were measured on a standard 15‑point scale ranging from 6 (very, very light) to 20 (exhausted).
A study in Sweden looked at former elite soccer players, people who had played soccer but not at the elite level, and people of the same age who did not play soccer. Here is a two-way table that classifies these subjects by whether or not they had arthritis of the hip or knee by their mid-fifties:
Elite
Non-elite
Did not play
Arthritis
10
9
24
No arthritis
61
206
548
Based on this study, you can conclude that
Chapter 2 Solutions
Introduction To Statistics And Data Analysis
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