Exam 12: Nonparametric Statistics

Use the following data for the next questions. Researchers studying sleep loss followed the length of sleep, in hours, of 10 individuals with insomnia before and after cognitive behavioral therapy (CBT). Use the Wilcoxon Signed-Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -Determine the value of the T test statistic.

Use the following sample data to answer the next questions. The paired data consist of the temperatures (in °F ) on randomly chosen days and the growth of certain kind of plant (in millimeters). Use the Spearman's rank correlation coefficient to test for a correlation between the temperature and the plant growth. Use a significance level of . -Determine the value of the test statistic.

Use the following sample data to answer the next questions. Certain creeks tend to accumulate sandbars that block water flow and negatively affect surface insect habitat. Biologists researching the formation and erosion of these sandbars attempted to discourage sandbar buildup by installing wood structures that would increase erosion in the creekbed. Researchers added differing numbers of wood structures to two similar, adjacent study creeks. The response of surface insects to the addition of wood structures was then measured by randomly sampling the weights (in grams) of surface insects at 11 equally-sized locations in the creeks. Use the Wilcoxon Rank-Sum Test with a .05 significance level to test the claim that, after adding the wood structures, both creeks have samples that come from populations with the same median of weights of surface insects. -Identify the null hypothesis and alternative hypothesis.

Use the following sample data to answer the next questions. Tracking misdiagnoses by Emergency Room doctors, a sample of 200 patients revealed that 45 patients were misdiagnosed with indigestion instead of a heart attack. Use the Sign test with a .05 significance level to test the claim that physicians correctly diagnose a majority of heart attacks. -State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

Use the following sample data to answer the next questions. Geneticists studying carriers of genetic diseases followed subjects subdivided by race. Researchers randomly selected seven patients per race who had been identified as carrying a certain gene for a genetic disease; these patients were followed to determine the number of their siblings who also carried the gene for the genetic disease. Use the Kruskal-Wallis Test at a .05 significance level to test the claim that the different races have samples that come from populations with equal medians of siblings who also carry the gene. -Determine the value of the H test statistic.

Use the following sample data to answer the next questions. The paired data consist of the temperatures (in °F ) on randomly chosen days and the growth of certain kind of plant (in millimeters). Use the Spearman's rank correlation coefficient to test for a correlation between the temperature and the plant growth. Use a significance level of . -Identify the critical value .

Use the following sample data to answer the next questions. The paired data consist of a random sample of the cost of regionally advertising (in thousands of dollars) a certain pharmaceutical drug and the number of new prescriptions written (in thousands). Use the Spearman's rank correlation coefficient to test for a correlation between the cost of advertising and the number of new prescriptions written. Use a significance level of . -State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

Use the following sample data to answer the next questions. Tracking misdiagnoses by Emergency Room doctors, a sample of 200 patients revealed that 45 patients were misdiagnosed with indigestion instead of a heart attack. Use the Sign test with a .05 significance level to test the claim that physicians correctly diagnose a majority of heart attacks. -Determine the value of the z test statistic.

Use the following sample data to answer the next questions. Certain creeks tend to accumulate sandbars that block water flow and negatively affect fish habitat. Biologists researching the formation and erosion of these sandbars attempted to discourage sandbar buildup by installing wood structures that would increase erosion in the creekbed. Researchers added differing numbers of wood structures to two similar, adjacent study creeks. Fish response was then measured by randomly sampling the number of fish at 11 equally-sized portions of the creeks. Use the Wilcoxon Rank-Sum Test with a .05 significance level to test the claim that, after adding the wood structures, both creeks have samples that come from populations with the same median number of native fish. -Determine the value of the test statistic.

Use the following data for the next questions. Ophthalmologists studying the treatment of using an infrared laser procedure in ten patients with vision loss caused by dry age-related macular degeneration (AMD) found the following data on visual acuity (VA) before and after the procedure. Use the Wilcoxon Signed- Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

Use the following sample data to answer the next questions. For a study on Type 1 diabetes, medical graduate students subdivided the United States into four study regions (Northeast, Southeast, Southwest, and Northwest). The students randomly selected seven patients per region and recorded the number of times on a randomly selected day that each patient used insulin shots to regulate blood sugar levels. Use the Kruskal-Wallis Test at a .05 significance level to test the claim that the regions have samples that come from populations with equal medians of number of insulin shots. Number of times patients used insulin shots to regulate blood sugar levels -Identify the null hypothesis and alternative hypothesis.

Use the following data for the next questions. Researchers studying sleep loss followed the length of sleep, in hours, of 10 individuals with insomnia before and after cognitive behavioral therapy (CBT). Use the Wilcoxon Signed-Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -Identify the critical value T .

Use the following data for the next questions. Ophthalmologists studying the treatment of using an infrared laser procedure in ten patients with vision loss caused by dry age-related macular degeneration (AMD) found the following data on visual acuity (VA) before and after the procedure. Use the Wilcoxon Signed- Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -Identify the critical value T .

Use the following data for the next questions. Researchers studying sleep loss followed the length of sleep, in hours, of 10 individuals with insomnia before and after cognitive behavioral therapy (CBT). Use the Wilcoxon Signed-Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -Identify the null hypothesis and alternative hypothesis.

Use the following sample data to answer the next questions. The paired data consist of the temperatures (in °F ) on randomly chosen days and the growth of certain kind of plant (in millimeters). Use the Spearman's rank correlation coefficient to test for a correlation between the temperature and the plant growth. Use a significance level of . -Identify the null hypothesis and alternative hypothesis.

Use the following sample data to answer the next questions. For a study on Type 1 diabetes, medical graduate students subdivided the United States into four study regions (Northeast, Southeast, Southwest, and Northwest). The students randomly selected seven patients per region and recorded the number of times on a randomly selected day that each patient used insulin shots to regulate blood sugar levels. Use the Kruskal-Wallis Test at a .05 significance level to test the claim that the regions have samples that come from populations with equal medians of number of insulin shots. Number of times patients used insulin shots to regulate blood sugar levels -Determine the value of the H test statistic.

Use the following sample data to answer the next questions. For a study on Type 1 diabetes, medical graduate students subdivided the United States into four study regions (Northeast, Southeast, Southwest, and Northwest). The students randomly selected seven patients per region and recorded the number of times on a randomly selected day that each patient used insulin shots to regulate blood sugar levels. Use the Kruskal-Wallis Test at a .05 significance level to test the claim that the regions have samples that come from populations with equal medians of number of insulin shots. Number of times patients used insulin shots to regulate blood sugar levels -State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

Use the following data for the next questions. Researchers studying sleep loss followed the length of sleep, in hours, of 10 individuals with insomnia before and after cognitive behavioral therapy (CBT). Use the Wilcoxon Signed-Ranks Test with a .05 significance level to test the claim that both samples come from populations having differences with a median equal to zero. -State a conclusion about the null hypothesis and a final conclusion that addresses the original claim.

Use the following sample data to answer the next questions. In order to evaluate patient response to a course of therapy to treat brain tumors, a sample of 300 patients revealed that 196 patients were responsive to a certain course of treatment. Use the Sign test with a .05 significance level to test the claim that a majority of patients with brain tumors were responsive to treatment. -Identify the critical value.

Use the following sample data to answer the next questions. Geneticists studying carriers of genetic diseases followed subjects subdivided by race. Researchers randomly selected seven patients per race who had been identified as carrying a certain gene for a genetic disease; these patients were followed to determine the number of their siblings who also carried the gene for the genetic disease. Use the Kruskal-Wallis Test at a .05 significance level to test the claim that the different races have samples that come from populations with equal medians of siblings who also carry the gene. -Identify the null hypothesis and alternative hypothesis.