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A sample of n 8 scores has a mean of m 10 after one

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37. A sample of n = 8 scores has a mean of M = 10. After one score is removed from the sample, the mean for the remaining score is found to be M = 11. What was the score that was removed? a. X = 3 b. X = 7 c. X = 8 d. impossible to determine from the information provided 38. A population has SS= 100 and ±2 = 4. How many scores are in the population?

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39. What are the values for SS and variance for the following sample of n = 4 scores? Sample: 1, 1, 0, 4 40. A population of scores has a mean of µ = 26, a median of 23, and a mode of 22. What is the most likely shape for the population distribution?
Short Answer 1 (10 pts): RESEARCH STUDY 5.4 Dr. Li is interested in creating a measurement of religiosity. According to the dictionary, religiosity is “the quality of being religious; piety; devoutness.” He creates a measure comprising 10 statements. People respond to each statement using the following scale (1 = strongly disagree, 3 = neither agree nor disagree, 5 = strongly agree). Some of the statements are below. Statement 1: “I believe in a religion.” Statement 2: “Part of who I am stems from my religious beliefs.” Statement 3: “I believe that religion is unnecessary.” a) Name two types of reliability that apply to Dr. Li’s measure and how each one could be established, given the above scenario. b) Dr. Li gives his new measure to a group of 100 adults in order to test the internal validity of his measure. Draw two scatterplots: one that demonstrates the likely relationship between Statement 1 and Statement 2 and one that demonstrates the likely relationship between Statement 1 and Statement 3. Explain why you have drawn each scatterplot as you have. c) Dr. Li gives his new measure to a group of 100 adults in order to test the internal validity of his measure. What type of correlation coefficients (r) would Dr. Li expect to find between Statement 1 and Statement 2 and between Statement 1 and Statement 3? What would these correlation coefficients tell Dr. Li about the internal reliability of his measure? d) Provide a suggestion for how Dr. Li could establish the criterion validity of his measure.

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Short Answer 2 (10 pts): RESEARCH STUDY 7.2 Dr. Parrett is a sports psychologist for a large Southern university. The provost and chancellor have asked him to examine the relationship between athletic performance and academic stress at the university. For example, is it the case that the most talented athletes experience the greatest concern over their grades? The provost and chancellor have made it clear to Dr. Parrett that they want a large amount of external validity in the study. He has valid and reliable measures of both athletic performance and academic stress. He knows that he does not have the time or the money to study the entire population of interest. a) What is the population of interest in Dr. Parrett’s study? Will he be collecting a sample or conducting a census? Why does he need to be concerned with external validity/representativeness? b) Describe the three sampling problems that could lead to a biased sample for Dr. Parrett. c) What is the difference between a cluster technique and a stratified technique? Explain why Dr. Parrett would be advised to use a cluster or a stratified technique rather than a simple random sample. d) Imagine that Dr. Parrett wants to use a nonrepresentative sampling technique. Name the three types of nonprobability sampling and explain how each one could be used by Dr. Parrett.
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• Spring '12
• StephanieMilan
• Vanessa, Dr. Li

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