Elementary Statistics (13th Edition)
13th Edition
ISBN: 9780134462455
Author: Mario F. Triola
Publisher: PEARSON
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Chapter 9.2, Problem 12BSC
In Exercises 5–20, assume that the two samples are independent simple random samples selected from
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 tire 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 (13th Edition)
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...
Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Prob. 16BSCCh. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Testing Claims About Proportions. In Exercises...Ch. 9.1 - Prob. 23BBCh. 9.1 - Yawning and Fishers Exact Test In one segment of...Ch. 9.1 - Overlap of Confidence Intervals In the article On...Ch. 9.1 - Equivalence of Hypothesis Test and Confidence...Ch. 9.2 - Independent and Dependent Samples Which of the...Ch. 9.2 - Confidence Interval for Hemoglobin Large samples...Ch. 9.2 - Hypothesis Tests and Confidence Intervals for...Ch. 9.2 - Degrees of Freedom For Example 1 on page 431, we...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - In Exercises 520, assume that the two samples are...Ch. 9.2 - Larger Data Sets. In Exercises 2124, use the...Ch. 9.2 - Larger Data Sets. In Exercises 2124, use the...Ch. 9.2 - Larger Data Sets. In Exercises 2124, use the...Ch. 9.2 - Larger Data Sets. In Exercises 2124, use the...Ch. 9.2 - Pooling Repeat Exercise 12 IQ and Lead by assuming...Ch. 9.2 - Degrees of Freedom In Exercise 20 Blanking Out on...Ch. 9.2 - No Variation in a Sample An experiment was...Ch. 9.3 - True? For the methods of this section, which of...Ch. 9.3 - Notation Listed below are body temperatures from...Ch. 9.3 - Units of Measure If the values listed in Exercise...Ch. 9.3 - Degrees of Freedom If we use the sample data in...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - Prob. 11BSCCh. 9.3 - Prob. 12BSCCh. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - In Exercises 516, use the listed paired sample...Ch. 9.3 - Prob. 17BSCCh. 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 - 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? Listed below are...Ch. 9 - Hypotheses Identify the null and alternative...Ch. 9 - Test Statistics Identify the test statistic that...Ch. 9 - Denomination Effect In the article The...Ch. 9 - Denomination Effect Construct the confidence...Ch. 9 - Heights Listed below are heights (cm) randomly...Ch. 9 - Heights Use a 0.01 significance level with the...Ch. 9 - Before /After Treatment Results Captopril is a...Ch. 9 - Eyewitness Accuracy of Police Does stress affect...Ch. 9 - Are Flights Cheaper When Scheduled Earlier? Listed...Ch. 9 - Variation of Heights Use the sample data given in...Ch. 9 - Family Heights. In Exercises 15, use the following...Ch. 9 - Scatterplot Construct a scatterplot of the...Ch. 9 - Family Heights. In Exercises 1-5, use the...Ch. 9 - Family Heights. In Exercises 1-5, use the...Ch. 9 - Assessing Normality Interpret the normal quantile...Ch. 9 - Braking Reaction Times: Histogram Listed below are...Ch. 9 - Braking Reaction Times: Normal? The accompanying...Ch. 9 - Braking Reaction Times: Boxplots Use the same data...Ch. 9 - In Exercises 5-20, assume that the two samples are...Ch. 9 - Braking Reaction Times: Confidence Intervals a....Ch. 9 - FROM DATA TO DECISION Critical Thinking: Did the...Ch. 9 - Critical Thinking: Did the NFL Rule Change Have...Ch. 9 - Critical Thinking: Did the NFL Rule Change Have...
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