Concept explainers
Mental health again Refer to the previous exercise.
- a. Report the test statistic and P-value for testing H0: β1 = β2 = 0.
- b. State the alternative hypothesis that is supported by the result in part a.
- c. Does the result in part a imply that necessarily both life events and SES are needed in the model? Explain.
13.28 Regression for mental health A study in Alachua County, Florida, investigated an index of mental health impairment, which had
- a. Find the 95% confidence interval for β1.
- b. Explain why the interval in part a means that an increase of 100 units in life events corresponds to anywhere from a 4- to 17-unit increase in mean mental impairment, controlling for SES. (This lack of precision reflects the small sample size.)
y = mental impairment, x1 = life events index, and x2 = socioeconomic status
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Statistics: The Art and Science of Learning from Data (4th Edition)
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