# Question

Data on pollution and cost of medical care for elderly people were given in Exercise 5.14 and are also shown here. The accompanying data are a measure of pollution (micrograms of particulate matter per cubic meter of air) and the cost of medical care per person over age 65 for six geographic regions of the United States.

Data set is y^ = 1082.2 2 4.691x, where y ≈ medical cost and x ≈ pollution.

a. Compute the six residuals.

b. What is the value of the correlation coefficientfor this data set? Does the value of r indicate that the linear relationship between pollution and medical cost is strong, moderate, or weak? Explain.

c. Construct a residual plot. Are there any unusual features of the plot?

d. The observation for the West, (40.0, 899), has an x value that is far removed from the other x values in the sample. Is this observation influential in determining the values of the slope and/or intercept of the least-squares line? Justify your answer.

Data set is y^ = 1082.2 2 4.691x, where y ≈ medical cost and x ≈ pollution.

a. Compute the six residuals.

b. What is the value of the correlation coefficientfor this data set? Does the value of r indicate that the linear relationship between pollution and medical cost is strong, moderate, or weak? Explain.

c. Construct a residual plot. Are there any unusual features of the plot?

d. The observation for the West, (40.0, 899), has an x value that is far removed from the other x values in the sample. Is this observation influential in determining the values of the slope and/or intercept of the least-squares line? Justify your answer.

## Answer to relevant Questions

Northern flying squirrels eat lichen and fungi, which makes for a relatively low quality diet. The authors of the paper “Nutritional Value and Diet Preference of Arboreal Lichens and Hypogeous Fungi for Small Mammals in ...The article “Examined Life: What Stanley Kaplan Taught Us About the SAT” (The New Yorker [December 17, 2001]: 86–92) included a summary of findings regarding the use of SAT I scores, SAT II scores, and high school ...With a bit of algebra, we can show that a. For what value of r is se as large as sy? What is the least-squares line in this case? r = 0, y^ = y b. For what values of r will se be much smaller than sy? c. A study by the ...Researchers have examined a number of climatic variables in an attempt to understand the mechanisms that govern rainfall runoff. The paper “The Applicability of Morton’s and Penman’s Evapotranspiration Estimates in ...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 a ...Post your question

0