ELEMENTARY STATISTICS
13th Edition
ISBN: 9780135959732
Author: Triola
Publisher: PEARSON
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Chapter 9.2, Problem 25BB
Pooling Repeat Exercise 12 “IQ and Lead” by assuming that the two population standard deviations are equal, so σ1 = σ2. Use the appropriate method from Part 2 of this section. Does pooling the standard deviations yield results showing greater significance?
12. IQ and Load Exposure Data Set 7 “IQ and Lead” in Appendix B lists full IQ scores for a random sample of subjects with low lead levels in their blood and another random sample of subjects with high lead levels in their blood. The statistics are summarized below.
a. Use a 0.05 significance level to test the claim that the mean IQ score of people with low blood lead levels is higher than the mean IQ score of people with high blood lead levels.
b. Construct a confidence interval appropriate for the hypothesis test in part (a).
c. Does exposure to lead appear to have an effect on IQ scores?
Low Blood Lead Level: n = 78,
High Blood Lead Level: n = 21,
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Chapter 9 Solutions
ELEMENTARY STATISTICS
Ch. 9.1 - Verifying Requirements In the largest clinical...Ch. 9.1 - Verifying Requirements In the largest clinical...Ch. 9.1 - Hypotheses and Conclusions Refer to the hypothesis...Ch. 9.1 - Using Confidence Intervals a. Assume that we want...Ch. 9.1 - Interpreting Displays. In Exercises 5 and 6, use...Ch. 9.1 - Treating Carpal Tunnel Syndrome Carpal tunnel...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Accuracy of Fast Food Drive-Through Orders In a...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...
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In Exercises 1724, use the...Ch. 9.3 - Larger Data Sets. In Exercises 1724, use the...Ch. 9.3 - Larger Data Sets. In Exercises 1724, use the...Ch. 9.3 - Larger Data Sets. In Exercises 1724, use the...Ch. 9.3 - Prob. 23BSCCh. 9.3 - Prob. 24BSCCh. 9.3 - Body Temperatures Refer to Data Set 3 Body...Ch. 9.4 - F Test Statistic a. If s12 represents the larger...Ch. 9.4 - F Test if using the sample data in Data Set 1 Body...Ch. 9.4 - Testing Normality For the hypothesis test...Ch. 9.4 - Prob. 4BSCCh. 9.4 - In Exercises 516, test the given claim. 5. Color...Ch. 9.4 - In Exercises 516, test the given claim. 6. Color...Ch. 9.4 - In Exercises 516, test the given claim. 7. Testing...Ch. 9.4 - In Exercises 516, test the given claim. 8....Ch. 9.4 - In Exercises 516, test the given claim. 9. Coke...Ch. 9.4 - In Exercises 516, test the given claim. 10. IQ and...Ch. 9.4 - Prob. 11BSCCh. 9.4 - Prob. 12BSCCh. 9.4 - Prob. 13BSCCh. 9.4 - Prob. 14BSCCh. 9.4 - In Exercises 516, test the given claim. 15. Old...Ch. 9.4 - In Exercises 516, test the given claim. 16....Ch. 9.4 - Prob. 17BBCh. 9.4 - Prob. 18BBCh. 9.4 - Finding Lower Critical F Values For hypothesis...Ch. 9 - In Exercises 15, use the following survey results:...Ch. 9 - In Exercises 1-5, use the following survey...Ch. 9 - In Exercises 1-5, use the following survey...Ch. 9 - In Exercises 1-5, use the following survey...Ch. 9 - In Exercises 7-5, use the following survey...Ch. 9 - True? Determine whether the following statement is...Ch. 9 - True? When we collect random samples to test the...Ch. 9 - Dependent or Independent? 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