Question

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DUUNIO ISI 1 Scatterplot The following scatterplot shows a relationship between x and y that results in a correlation coefficient of r=0. Explain why 0 in this situation even though there appears to be strong relationship between the x and y Variables Scatterplot of ysx 2 Multiple Choice All but one of the statements below contain a mistake. Which one could be true? a) If the correlation between blood alcohol level and reaction time is 0.73, then the correlation between reaction time and blood alcohol level is -0.73. b) The correlation between the breed of a cat and its weight is 0.435. c) The correlation between race and age is 0.171. d) The correlation between weight and height is 0.627 pounds per inch. e) The correlation between weight and length of the middle finger is 0.412. 3 Box Plots The chemicals in clay used to make pottery can differ depending on the geographical region where the clay originated. Sometimes, archaeologists use a chemical analysis of clay to help identify where a piece of pottery originated. Such an analysis measures the amount of a chemical in the clay as a percent of the total weight of the piece of pottery. The boxplots below summarize analyses done for three chemicals-X, Y, and 7-on pieces of potery that originated at one of three sites: I, II, or III.

Answer 1

1. The correlation coefficient r is a statistical tool that measures the degree of linear relationship between two variables. It ranges from -1 to 1 with 1 being perfect positive correlation between the variables. The scatterplot shows a clear relationship between x and y, however r=0. This is possible because while r=0 implies no LINEAR correlation between the two variables, there is always a possibility of non-linear correlation between the variables as shown in the scatterplot above.

2. Option d) could be correct. Many studies have found a strong linear relationship between height and weight of a person.