RESEARCH METHODS-W/ACCESS >CUSTOM<
5th Edition
ISBN: 9781305743625
Author: GRAVETTER
Publisher: CENGAGE C
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Chapter 7, Problem 2EA
A researcher examines the relationship between the quality of breakfast and academic performance for a group of elementary-school children. For each child, the researcher interviews the parents to obtain information about the child’s typical breakfast, and uses school records to obtain a measure of academic performance.
- Explain why this study is not a true experiment.
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Customers experiencing technical difficulty with their Internet cable service may call an 800 number for technical support. It takes the technician between 30 seconds and 11 minutes to resolve the problem. The distribution of this support time follows the uniform distribution.
Required:
a. What are the values for a and b in minutes?
Note: Do not round your intermediate calculations. Round your answers to 1 decimal place.
b-1. What is the mean time to resolve the problem?
b-2. What is the standard deviation of the time?
c. What percent of the problems take more than 5 minutes to resolve?
d. Suppose we wish to find the middle 50% of the problem-solving times. What are the end points of these two times?
Chapter 7 Solutions
RESEARCH METHODS-W/ACCESS >CUSTOM<
Ch. 7.1 - Describe the general purpose of an experimental...Ch. 7.1 - Define independent, dependent, and extraneous...Ch. 7.1 - Describe the third-variable problem and the...Ch. 7.2 - Explain why manipulation of an independent...Ch. 7.2 - Explain why control of extraneous variables is a...Ch. 7.2 - Explain how an extraneous variable can become a...Ch. 7.3 - Describe the three primary techniques for...Ch. 7.4 - Describe the purpose for control conditions in...Ch. 7.4 - Explain when a manipulation check is needed,...Ch. 7.5 - Define field studies and simulation, explain why...
Ch. 7 - In addition to the key words, you should also be...Ch. 7 - Dr. Jones conducted a study examining the...Ch. 7 - In an experiment examining human memory, two...Ch. 7 - It has been demonstrated that students with high...Ch. 7 - A researcher would like to compare two methods for...Ch. 7 - Define extraneous variable and explain how...Ch. 7 - Identify the two characteristics needed for a...Ch. 7 - Identify the two active methods of preventing...Ch. 7 - Explain how the process of randomly assigning...Ch. 7 - Can a research study be an experiment without a...Ch. 7 - What is the general purpose of a manipulation...Ch. 7 - What is the general purpose for using a simulation...Ch. 7 - Prob. 1EACh. 7 - A researcher examines the relationship between the...
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