12th Edition

ISBN: 9780321837936

Author: Mario F. Triola

Publisher: PEARSON

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Statistics is the study of data collection, organization, analysis, interpretation, and presentation. Statistical bias is a characteristic of a statistical technique or its findings in which the expected value deviates from the actual root quantitative p…

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Textbook Question

Chapter 9, Problem 3FDD

Critical Thinking: Ages of workers killed in the Triangle Factory fire Listed below are the ages (years) of the 146 employees who perished in the Triangle Factory fire that occurred on March 25, 1911 in Manhattan (based on data from the Kheel Center and the New York Times). One factor contributing to the large number of deaths is that almost all exits were locked so that employees could be checked for theft when they finished work at the end of the day. That fire revealed grossly poor and unsafe working conditions that led to changes in building codes and labor laws.

Analyzing the Results

1. First explore the combined male and female ages using suitable statistics and graphs. What is the mean age? What are the minimum and maximum ages? What is the standard deviation of the ages? Are there any outliers? Describe the distribution of the ages.
2. Examination of the two lists shows that relatively few men perished in the fire. Treat the ages as sample data and determine whether there is sufficient evidence to support the claim that among the workers who perish in such circumstances, the majority are women.
3. Construct a 95% confidence interval estimate of the mean age of males and construct another 95% confidence interval estimate of the mean age of females. Compare the results.
4. Treat the ages as sample data and determine whether there is sufficient evidence to support the claim that female workers have a mean age that is less than that of male workers.
5. Treat the ages as sample data and determine whether there is sufficient evidence to support the claim that ages of males and females have different standard deviations.
6. Based on the preceding results, identify any particularly notable features of the data.

Males

Females

24	16	25	31	22	18	19	22	16	23	17	15	21	18	17	17	17	31	20	36
18	25	30	16	25	25	21	19	17	18	20	18	26	26	16	18	18	17	22	17
20	22	18	20	16	25	18	40	21	18	19	19	18	18	19	16	19	16	16	21
33	21	14	22	19	10	23	10	18	21	39	20	14	27	22	15	10	16	16	19
18	21	18	10	10	20	18	43	16	20	18	30	21	22	18	21	35	22	21	22
21	22	17	24	25	20	18	32	20	21	19	24	17	18	30	18	16	22	22	17
22	20	15	20	17	21	21	18	17

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Chapter 9, Problem 2FDD

Chapter 9, Problem 4FDD

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Chapter 9 Solutions

Elementary Statistics

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24	16	25	31	22	18	19	22	16	23	17	15	21	18	17	17	17	31	20	36
18	25	30	16	25	25	21	19	17	18	20	18	26	26	16	18	18	17	22	17
20	22	18	20	16	25	18	40	21	18	19	19	18	18	19	16	19	16	16	21
33	21	14	22	19	10	23	10	18	21	39	20	14	27	22	15	10	16	16	19
18	21	18	10	10	20	18	43	16	20	18	30	21	22	18	21	35	22	21	22
21	22	17	24	25	20	18	32	20	21	19	24	17	18	30	18	16	22	22	17
22	20	15	20	17	21	21	18	17

24	16	25	31	22	18	19	22	16	23	17	15	21	18	17	17	17	31	20	36
18	25	30	16	25	25	21	19	17	18	20	18	26	26	16	18	18	17	22	17
20	22	18	20	16	25	18	40	21	18	19	19	18	18	19	16	19	16	16	21
33	21	14	22	19	10	23	10	18	21	39	20	14	27	22	15	10	16	16	19
18	21	18	10	10	20	18	43	16	20	18	30	21	22	18	21	35	22	21	22
21	22	17	24	25	20	18	32	20	21	19	24	17	18	30	18	16	22	22	17
22	20	15	20	17	21	21	18	17

Solution Summary: The author compares the 95% confidence interval estimate of the mean age of males and the 95-year-old females in the triangle factory fire in 1911.

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Chapter 9 Solutions

24	16	25	31	22	18	19	22	16	23	17	15	21	18	17	17	17	31	20	36
18	25	30	16	25	25	21	19	17	18	20	18	26	26	16	18	18	17	22	17
20	22	18	20	16	25	18	40	21	18	19	19	18	18	19	16	19	16	16	21
33	21	14	22	19	10	23	10	18	21	39	20	14	27	22	15	10	16	16	19
18	21	18	10	10	20	18	43	16	20	18	30	21	22	18	21	35	22	21	22
21	22	17	24	25	20	18	32	20	21	19	24	17	18	30	18	16	22	22	17
22	20	15	20	17	21	21	18	17