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Unformatted text preview: ST520, Fall 2011 Homework 1, due: Wednesday, 8/31/2011 1. (10 pts) In a case-control study conducted in French sometime ago to investigate the association between esophageal cancer and alcohol assumption, the following data was collected from 200 cases and 775 controls (so the total sample size is 975) Alcohol assumption Case Control Heavy 96 109 Light 104 666 where Heavy is defined as Average daily alcohol assumption 80 g, Light is defined as Average daily alcohol assumption < 80 g. An investigator produced following estimates. Indicate which is correct and which is wrong. State your reasons. (a) The proportion of heavy drinkers in French was estimated to be 205/975=0.21. (b) The proportion of french people having an esophageal cancer was estimated to be 200/975 = 0.21. (c) The probability of having an esophageal cancer among heavy drinkers was estimated to be 96/205=0.47. (d) The probability of having an esophageal cancer among light drinkers was estimated to be 104/775 = 0.13. (e) The relative risk of having an esophageal cancer between heavy drinkers and light drinkers was estimated to be 0.47/0.13=3.62. So heavy drinkers are 3.62 times as likely to have an esophageal cancer as light drinkers.esophageal cancer as light drinkers....
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This note was uploaded on 09/15/2011 for the course STATISTICS ST 520 taught by Professor Dr.zhang during the Fall '11 term at N.C. State.
- Fall '11