Bundle: Essentials of Statistics for The Behavioral Sciences, Loose-Leaf Version, 9th + LMS Integrated Aplia, 1 term Printed Access Card
9th Edition
ISBN: 9781337593885
Author: GRAVETTER
Publisher: CENGAGE L
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Chapter 15, Problem 7P
Automobile insurance is much more expensive for teenage drivers than for older drivers. To justify this cost difference, insurance companies claim that the younger drivers are much more likely to be involved in costly accidents. To test this claim, a researcher obtains information about registered drivers from the department of motor vehicles and selects a sample of n = 300 accident reports from the police department. The motor vehicle department reports the percentage of registered drivers in each age category’ as follows; 16% are younger than age 20; 28% are 20 to 29 years old; and 56% are age 30 or older. The number of accident reports for each age group is as follows:
- a. Do the data indicate that the distribution of accidents for the three age groups is significantly different from the distribution of drivers? Test with α = .05.
- b. Compute Cohen’s w to measure the size of the effect
- c. Write a sentence demonstrating how the outcome of the hypothesis test and the measure of effect size would appear in a research report.
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Chapter 15 Solutions
Bundle: Essentials of Statistics for The Behavioral Sciences, Loose-Leaf Version, 9th + LMS Integrated Aplia, 1 term Printed Access Card
Ch. 15.1 - Which of the following is a characteristic of...Ch. 15.1 - Which of the following accurately describes the...Ch. 15.1 - A researcher uses a sample of n = 60 participants...Ch. 15.2 - Prob. 1LCCh. 15.2 - Prob. 2LCCh. 15.2 - A researcher uses a sample of 20 college...Ch. 15.3 - If a chi-square test for independence has df 3,...Ch. 15.3 - Prob. 2LCCh. 15.3 - Prob. 3LCCh. 15.4 - Prob. 1LC
Ch. 15.4 - A researcher obtains X2 = 4.0 for a test for...Ch. 15.4 - Under what circumstances should the chi-square...Ch. 15.5 - Prob. 1LCCh. 15.5 - Prob. 2LCCh. 15 - Prob. 1PCh. 15 - The student population at the state college...Ch. 15 - A developmental psychologist would like to deter...Ch. 15 - Data from the Department of Motor Vehicles...Ch. 15 - A psychologist examining art appreciation selected...Ch. 15 - A professor in the psychology department would...Ch. 15 - Automobile insurance is much more expensive for...Ch. 15 - A communications company has developed three new...Ch. 15 - Prob. 9PCh. 15 - Earlier in the chapter, we introduced the...Ch. 15 - Liu el al. (2015) recently reported the results of...Ch. 15 - Many businesses use some type of customer loyalty...Ch. 15 - In a classic study, Loftus and Palmer (1974)...Ch. 15 - In a study investigating freshman weight pain, the...Ch. 15 - Research results suggest that IQ scores for boys...Ch. 15 - Gender differences in dream content are well...Ch. 15 - Many parents allow their underage children to...Ch. 15 - A recent study indicates that people tend to...Ch. 15 - Research indicates that people who volunteer to...Ch. 15 - Research has demonstrated strong gender...
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