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Question: The authors of the paper “Flat-Footedness

The authors of the paper “Flat-Footedness is not a Disadvantage for athletic Performance in Children aged 11 to 15 Years” (Pediatrics [2009]: e386–e392) studied the relationship between y = Arch height and scores on five different motor ability tests. They reported the following correlation coefficients:
The authors of the paper “Flat-Footedness is not a Disadvantage for athletic Performance in Children aged 11 to 15 Years” (Pediatrics [2009]: e386–e392) studied the relationship between y = Arch height and scores on five different motor ability tests. They reported the following correlation coefficients:


a. Interpret the value of the correlation coefficient between average hopping height and arch height. What does the fact that the correlation coefficient is negative say about the relationship? Do larger arch heights tend to be paired with larger or smaller average hopping heights? 
b. The title of the paper suggests that having a small value for Arch height (flat-footedness) is not a disadvantage when it comes to motor skills. Do the given correlation coefficients support this conclusion? Explain.

a. Interpret the value of the correlation coefficient between average hopping height and arch height. What does the fact that the correlation coefficient is negative say about the relationship? Do larger arch heights tend to be paired with larger or smaller average hopping heights? b. The title of the paper suggests that having a small value for Arch height (flat-footedness) is not a disadvantage when it comes to motor skills. Do the given correlation coefficients support this conclusion? Explain.





Transcribed Image Text:

Correlation Between Test Motor Ability Test Score and Arch Height Height of counter movement jump -0.02 Hopping: average height -0.10 Hopping: average power -0.09 Balance, closed eyes, one leg 0.04 Toe flexion 0.05


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> To learn how the amount of money spent on a fast-food meal might differ for men and women, the amount spent on lunch at a particular fast-food restaurant was determined for each person in a sample of 50 women and each person in a sample of 50 men. Requi

> To learn how GPA at the end of the freshman year in college is related to high school GPA, both high school GPA and freshman year GPA were determined for each student in a sample of 100 students who had just completed their freshman year at a particular

> Data on tipping percent for 20 restaurant tables, consistent with summary statistics given in the paper “racial and ethnic Differences in tipping: the role of Perceived Descriptive and injunctive tipping norms” (Restau

> To see if there is a difference in car color preferences of men and women, each person in a sample of 100 males and each person in a sample of 100 females was shown pictures of a new model car in five different colors and asked to select which color they

> To learn about the heights of five-year-old children, the height of each child in a sample of 40 five-year-old children was measured. Required: 1. How many variables are in the data set? 2. Are the variables in the data set categorical or numerical? 3

> For the following numerical variables, state whether each is discrete or continuous. a. The length of a 1-year-old rattlesnake b. The altitude of a location in California selected randomly by throwing a dart at a map of the state c. The distance from

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> For a given data set, the sum of squared deviations from the line y = 40 + 6x is 529.5. For this same data set, which of the following could be the sum of squared deviations from the least squares regression line? Explain your choice. i. 308.6 ii. 529

> The relationship between hospital patient-to-nurse ratio and various characteristics of job satisfaction and patient care has been the focus of a number of research studies. Suppose x = Patient-to-nurse ratio is the predictor variable. For each of the fo

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> For each of the following pairs of variables, indicate whether you would expect a positive correlation, a negative correlation, or a correlation close to 0. Explain your choice. a. Price and weight of an apple b. A person’s height and the number of pet

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2.99

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