10. A community researcher measured the correlation between the average cost of housing and the crime rate in eight local communities. The results of this hypothetical study are listed in the following table: Average cost of Housing (in thousands of dollars) Crime Rates (per 100,000 population) Y 20 96 80 65 220 22 120 31 180 34 90 70 110 30 300 16 a. Compute the Pearson correlation coefficient b. Compute the coefficient of determination c. Using a two-tailed test at a .05 level of significance, is your decision reject or fail to reject the nul hypothesis?

2. Use the first 30 data values in Table 1. Test, at the 5 percent level of significance, the hypothesis that men's and women's mean (a) Cholesterol (b) Blood pressure are equal, Table 1 Student Weight Cholesterol Pressure Gender Student Weight Cholesterol Pressure Gender 147 213 127 30 129 194 184 114 2 156 174 116 M 31 111 104 112 193 110 32 156 191 118 4 127 196 110 F 33 155 221 107 F 144 220 130 34 104 212 111 6. 140 183 99 35 217 221 156 M 119 194 112 36 132 103 204 117 139 200 102 F 37 204 121 9 161 192 121 38 171 191 105 M 10 146 200 125 39 135 183 110 11 190 200 125 M 40 249 227 137 M 12 126 199 133 41 185 188 119 M 13 164 178 130 42 194 200 109 M 14 176 183 136 43 165 197 123 M 15 131 188 112 F 44 121 208 100 16 107 193 113 45 124 218 102 17 116 187 112 46 113 194 119 18 157 181 129 M 47 110 212 119 F 19 186 193 137 48 136 207 99 20 189 205 196 113 M 49 221 219 149 21 147 113 50 151 201 109 F 22 112 211 110 F 51 182 208 130 M 23 209 202 97 M 52 151 192 107 M 24 135 213 103 F…

12. A study is conducted concerning automobile speeds and fuel consumption rates. The following data is collected: a. Plot these data in a scatter diagram. Speed MPG 44 22 51 26 48 21 60 28 33 32 66 61 b. Compute the coefficient of correlation. A B C D F G MPG Speed Y 22 44 26 51 21 48 28 60 33 66 32 61 n Total b. G. Determine at the 0.05 significance level whether the correlation in the population is greater than zero. с. c. 271 Linear Regression and Correlation Chapter 13

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35. Statistics students in Oxnard College sampled 10 textbooks in the Condor bookstore and recorded the number of pages in each textbook and its cost. The bivariate data are shown below: Number of Pages (xx) Cost(yy) 757 134.55 538 106.7 782 142.3 461 83.15 597 116.55 372 74.8 328 75.2 480 92 978 154.7 261 58.15 A student calculates a linear modely =           x +          . (Please show your answers to two decimal places)Use the model to estimate the cost when number of pages is 849.Cost =$                 (Please show your answer to 2 decimal places.)

A paper concluded that there was a correlation between refined sugar consumption (calories per person per day) and annual rate of major depression (cases per 100 people) based on data from six countries. The following data were read from a graph that appeared in the раper. Sugar Consumption Depression Rate Country Korea 160 2.4 United States 290 3.1 France 360 4.3 Germany 365 4.9 Canada 380 5.3 New Zealand 470 5.6 n USE SALT (a) Calculate the correlation coefficient for this data set. (Round your answer to four decimal places.) r = 0.9428 Interpret the correlation coefficient for this data set. O There is a weak, positive linear relationship between depression rate and sugar consumption. O There is no linear relationship between depression rate and sugar consumption. O There is a strong, negative linear relationship between depression rate and sugar consumption. O There is a weak, negative linear relationship between depression rate and sugar consumption. O There is a strong, positive…

9. Judge and Cable (2010) report the results of a study demonstrating a negative relationship between weight and income for a group of women professionals. Following are data similar to those obtained in the study. To simplify the weight variable, the women are classified into five categories that measure actual weight relative to height, from 1 = thinnest to 5 = heaviest. Income figures are annual income (in thousands), rounded to the nearest $1,000. a. Calculate the Pearson correlation for these data. b. Is the correlation statistically significant? Use a two-tailed test with .   Weight (X) Income (Y) 1 125 2 78 4 49 3 63 5 35 2 84 5 38 3 51 1 93 4 44

Correlation studies are often used to help determine whether certain characteristics are controlled more by genetic influences or by environmental influences. These studies often examine adopted children and compare their behaviors with the behaviors of their birth parents and their adoptive parents. One study examined how much time individuals spend watching TV (Plomin, Corley, DeFries, & Fulker, 1990). The following data are similar to the results obtained in the study. a. Compute the correlation between the children and their birth parents. b. Compute the correlation between the children and their adoptive parents. c. Based on the two correlations, does TV watching appear to be inherited from the birth parents or is it learned from the adoptive parents?

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