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Unformatted text preview: Single Population Proportion A hospital director believes that fewer than 57% of the lab reports contain errors. A sample of 170 reports found 85 errors. Use a 0.05 level of significance. Is there sufficient evidence to support the director’s claim? Determine the p-value of the test statistic. A newspaper publisher believes that more than 49% of their readership owns a Rolls Royce. A random sample of 210 found that 46% of the readers owned a Rolls Royce. Use a 0.02 level of significance. Is there sufficient evidence to support newspaper publisher’s claim. A sample of 1600 computer chips revealed that 23% of the chips did not fail in the first 1000 hours of their use. The company’s promotional literature claimed that 20% did not fail in the first 1000 hours of their use. Use a 0.02 level of significance. Make a decision to reject or fail to reject the null hypothesis. A newspaper publisher believes that 75% of their readership owns a personal computer. A random sample of 370 found that 71% of the readers owned a personal computer. Use 0.05 level of significance. Make a decision to reject or to fail to reject the null hypothesis. Determine the p-value. Two Population Proportion In a study of 200 adult female and 250 adult male internet users, 30% of the females and 38% of the males said that they plan to shop online at least once during the next month. Test the claim that there is a difference in the proportion of adult female and adult male internet users who plan to shop online. Use alpha = 0.05 The U.S. Census Bureau conducts annual surveys to obtain information on the percentage of the voting-age population that is registered to vote. Suppose that 490 employed persons 458 unemployed persons are independently and randomly selected, and that 253 of the employed persons and 186 of the unemployed persons have registered to vote. Can we conclude that the percentage of employed workers (p1), who have registered to vote, exceeds the percentage of unemployed workers (p2), who have registered to vote? Use a significance level of 0.1 for the test Sample Size Find the necessary sample size so that a 95% confidence interval will have a 0.05 margin of Find the necessary sample size so that a 95% confidence interval will have a 0....
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This note was uploaded on 03/12/2011 for the course DSCI 2710 taught by Professor Hossain during the Spring '08 term at North Texas.
- Spring '08