Bundle: Essentials of Statistics for The Behavioral Sciences, Loose-Leaf Version, 9th + Aplia, 1 term Printed Access Card
9th Edition
ISBN: 9781337593830
Author: Frederick J Gravetter, Larry B. Wallnau, Lori-Ann B. Forzano
Publisher: Cengage Learning
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Textbook Question
Chapter 15, Problem 6P
A professor in the psychology department would like to determine whether there has been a significant change in grading practices over the years. It is known that the overall grade distribution for the department in 1985 had 14% As. 26% Bs, 31% Cs. 19% Ds. and 10% Fs. A sample of n = 200 psychology students from last semester produced the following grade distribution:
Do the data indicate a significant change in the grade distribution? Test at the .05 level of significance.
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Chapter 15 Solutions
Bundle: Essentials of Statistics for The Behavioral Sciences, Loose-Leaf Version, 9th + 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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