STA 200 NAME Exercise 3 The purpose of this activity is for you to compute and interpret some measures of the relationship between two variables.1. In the relationship between student height and parent average height, which variable is the explanatory variable and which is the response variable?2. Draw a scatter plot of the data. Use the horizontal axis for the explanatory variable and the vertical axis for the response variable. Use different colors for males and females. Remember to label the axes and mark the scale on the axes.3. To interpret the scatterplot, answer the following questions. a) Overall, does the association appear to be linear? If it appears linear, is it positive or negative or zero? b) Write a statement about how students’ heights change based on parents’ average height. (For example, in describing the relationship between height and weight, one might say that as a person’s height increases their weight tends to increase.) c) Which point could be identified as an outlier? Explain the characteristics of the student who corresponds to this point.d) Now look only at the data points corresponding to female students. Does the association appear to be linear? If it appearslinear, is it positive or negative or zero?e) Now look only at the data about males. Does the association appear to be linear? If it appears linear, is it positive or negative or zero?4. The equation of the regression line for this data is:Student Height = 42.601 + .365 - Parent Average Height a) Sketch this line on your scatterplot. b) What is the intercept? Does it have a logical meaning in this example? If yes, what is it? If no, explain why not?c) What is the slope? Explain what this slope means in terms of thisexample. d) Predict the height of a student whose parents’ average height is 62 inches. e) Compare your prediction to the height for the student in the sample whose parents’ average height was 62 inches. How far isyour prediction from the actual student’s height?BONUS – Look at the scatterplot you drew in problem 2. The correlation coefficients for the following three pairs of variables are -.15, .32, and .88. Match the correlation coefficient to the correct relationship. A. Overall Student Height and Parents’ Height r = B. Female Student Height and Parents’ Height r = C. Male Student Height and Parents’ Height r = Now explain why you made your choice. (You only need to justify how you identified two of the three numbers.)STA 200 Data for Group Activity 4A simple random sample of 20 college students included 10 females and 10 males. Each student was asked to list their own height and the heights of their mother and father. The heights of their parents were averaged to calculate a new variable called Parent Average Height. StudentSexParent AverageHeight(in inches)Student Height(in inches)F 63 61F 65 66F 67 65F 70 66F 68 67F 61 62F 70 69F 62 63F 64 64F 69 67M 64 71M 68 71M 72 73M 66 67M 66 65M 71 72M 69 68M 61 75M 67 63M 70
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