Statistics for Business and Economics (13th Edition)
13th Edition
ISBN: 9780134506593
Author: James T. McClave, P. George Benson, Terry Sincich
Publisher: PEARSON
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Chapter 2.7, Problem 2.112ACB
Treating psoriasis with the “Doctorfish of Kangal.” Psoriasis is a skin disorder with no known cure and no proven effective pharmacological treatment. An alternative treatment for psoriasis is ichthyotherapy, also known as therapy with the “Doctorfish of Kangal.” Fish from the hot pools of Kangal, Turkey, feed on the skin scales of bathers, reportedly reducing the symptoms of psoriasis. In one study, 67 patients diagnosed with psoriasis underwent 3 weeks of ichthyotherapy (Evidence-Based Research in Complementary and Alternative Medicine. December 2006). The Psoriasis Area Severity Index (PASI) of each patient was measured both before and after treatment. (The lower the PASI score, the better is the skin condition.) Box plots of the PASI scores, both before (baseline) and after 3 weeks of ichthyotherapy treatment, are shown in the accompanying diagram.
- a. Find the approximate 25th percentile, the
median , and the 75th percentile for the PASI scores before treatment. - b. Find the approximate 25th percentile, the median, and the 75th percentile for the PAS I scores after treatment.
- c. Comment on the effectiveness of ichthyotherapy in treating psoriasis.
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Chapter 2 Solutions
Statistics for Business and Economics (13th Edition)
Ch. 2.1 - Complete the following table.Ch. 2.1 - A qualitative variable with three classes (X, Y,...Ch. 2.1 - STEM experiences for girls. The National Science...Ch. 2.1 - Cable TV subscriptions and cord cutters. Has the...Ch. 2.1 - Do social robots walk or roll? A social (or...Ch. 2.1 - Top credit card issuers, by region. The Nilson...Ch. 2.1 - Microsoft program security issues. To help its...Ch. 2.1 - Jamming attacks on wireless networks. Refer to the...Ch. 2.1 - The Apprentice contestants performance ratings....Ch. 2.1 - The economic return to earning an MBA. Refer to...
Ch. 2.1 - Profiling UK rental malls. An analysis of the...Ch. 2.1 - History of corporate acquisitions. A corporate...Ch. 2.1 - Twitter opinions of iPhone 6 features. What are...Ch. 2.1 - Museum management. What criteria do museums use to...Ch. 2.1 - Advertising with reader-response cards....Ch. 2.1 - Motivation and right-oriented bias. Evolutionary...Ch. 2.1 - Groundwater contamination in wells. In New...Ch. 2.2 - Graph the relative frequency histogram for the 500...Ch. 2.2 - Refer to Exercise 2.18. Calculate the number of...Ch. 2.2 - Consider the stem-and-leaf display shown here. a....Ch. 2.2 - Minitab was used to generate the following...Ch. 2.2 - Stability of compounds in new drugs. Testing the...Ch. 2.2 - Corporate sustainability of CPA firms. Refer to...Ch. 2.2 - Sanitation inspection of cruise ships. To minimize...Ch. 2.2 - History of corporate acquisitions. Refer to the...Ch. 2.2 - Most valuable NFL teams. Each year Forbes reports...Ch. 2.2 - State SAT scores. Educators are constantly...Ch. 2.2 - Items arriving and departing a work center. In a...Ch. 2.2 - Crude oil biodegradation. In order to protect...Ch. 2.2 - Volkswagen emissions scandal. Recently, the...Ch. 2.2 - Is honey a cough remedy? Does a teaspoon of honey...Ch. 2.2 - Time in bankruptcy. Financially distressed firms...Ch. 2.2 - Prob. 2.33ACACh. 2.2 - Prob. 2.34ACACh. 2.3 - Calculate the mean and median of the following...Ch. 2.3 - Calculate the mean for samples where a. n = 10, x...Ch. 2.3 - Explain how the relationship between the mean and...Ch. 2.3 - Explain the difference between the calculation of...Ch. 2.3 - Calculate the mode, mean, and median of the...Ch. 2.3 - Calculate the mean, median, and mode for each of...Ch. 2.3 - Describe how the mean compares to the median for a...Ch. 2.3 - Use the applet entitled Mean versus Median to find...Ch. 2.3 - Prob. 2.2AECh. 2.3 - Use the applet Mean versus Median to study the...Ch. 2.3 - Hotels use of ecolabels. Ecolabels such as Energy...Ch. 2.3 - Rankings of research universities. Based on...Ch. 2.3 - Performance of stock screeners. Investment...Ch. 2.3 - Performance-based logistics. Refer to the Journal...Ch. 2.3 - Surface roughness of oil field pipe. Oil field...Ch. 2.3 - Prob. 2.47ACICh. 2.3 - Corporate sustainability of CPA firms. Refer to...Ch. 2.3 - Is honey a cough remedy? Refer to the Archives of...Ch. 2.3 - Crude oil biodegradation. Refer to the Journal of...Ch. 2.3 - Symmetric or skewed? Would you expect the data...Ch. 2.3 - Prob. 2.52ACICh. 2.3 - Prob. 2.53ACACh. 2.3 - Prob. 2.54ACACh. 2.3 - Prob. 2.55ACACh. 2.4 - Answer the following questions about variability...Ch. 2.4 - Calculate the range, variance, and standard...Ch. 2.4 - Calculate the variance and standard deviation for...Ch. 2.4 - Compute x,s2, and s for each of the following data...Ch. 2.4 - Calculate the range, variance, and standard...Ch. 2.4 - Using only integers between 0 and 10, construct...Ch. 2.4 - Using only integers between 0 and 10, construct...Ch. 2.4 - Consider the following sample of five...Ch. 2.4 - Use the applet entitled Standard Deviation to find...Ch. 2.4 - Use the applet Standard Deviation to study the...Ch. 2.4 - Use the applet Standard Deviation to study the...Ch. 2.4 - Hotels use of ecolabels. Refer to the Journal of...Ch. 2.4 - Permeability of sandstone during weathering. Refer...Ch. 2.4 - Performance of stock screeners. Refer to the...Ch. 2.4 - Corporate sustainability of CPA firms. Refer to...Ch. 2.4 - Is honey a cough remedy? Refer to the Archives of...Ch. 2.4 - Active nuclear power plants. Refer to Exercise...Ch. 2.4 - Estimating production time. A widely used...Ch. 2.5 - The output from a statistical software package...Ch. 2.5 - Prob. 2.72LMCh. 2.5 - For a set of data with a mound-shaped relative...Ch. 2.5 - The following is a sample of 25 measurements: a....Ch. 2.5 - Given a data set with a largest value of 760 and a...Ch. 2.5 - Voltage sags and swells. The power quality of a...Ch. 2.5 - Permeability of sandstone during weathering. Refer...Ch. 2.5 - Do social robots walk or roll? Refer to the...Ch. 2.5 - College dropout study. The American Economic...Ch. 2.5 - Motivation of drug dealers. Consider a study of...Ch. 2.5 - Sanitation inspection of cruise ships. Refer to...Ch. 2.5 - Volkswagen emissions scandal. Refer to the...Ch. 2.5 - Auditing water resources in Australia. Australia...Ch. 2.5 - The Apprentice contestants performance ratings....Ch. 2.5 - Shopping vehicle and judgment. While shopping at...Ch. 2.5 - Buy-side vs. sell-side analysts earnings...Ch. 2.5 - Prob. 2.87ACACh. 2.5 - Improving SAT scores. The National Education...Ch. 2.5 - Prob. 2.89ACACh. 2.6 - Compute the z-score corresponding to each of the...Ch. 2.6 - Give the percentage of measurements in a data set...Ch. 2.6 - In terms of percentiles, define QL, QM and QU.Ch. 2.6 - Compare the z-scores to decide which of the...Ch. 2.6 - Suppose that 40 and 90 are two elements of a...Ch. 2.6 - Mathematics assessment test scores. According to...Ch. 2.6 - Prob. 2.96ACBCh. 2.6 - Prob. 2.97ACBCh. 2.6 - Sanitation inspection of cruise ships Refer to the...Ch. 2.6 - Prob. 2.99ACICh. 2.6 - Prob. 2.100ACICh. 2.6 - Executive networking and firm performance. Do...Ch. 2.6 - Blue- vs. red-colored exam study. In a study of...Ch. 2.6 - Ranking PhD programs in economics. Thousands of...Ch. 2.6 - Using z-scores for grades. At one university, the...Ch. 2.6 - Prob. 2.105ACACh. 2.7 - A sample data set has a mean of 57 and a standard...Ch. 2.7 - Suppose a data set consisting of exam scores has a...Ch. 2.7 - Consider the horizontal box plot shown below. a....Ch. 2.7 - Prob. 2.109LMCh. 2.7 - Prob. 2.7AECh. 2.7 - Rankings of research universities. Refer to the...Ch. 2.7 - Voltage sags and swells. Refer to the Electrical...Ch. 2.7 - Treating psoriasis with the Doctorfish of Kangal....Ch. 2.7 - Budget lapsing at army hospitals. Accountants use...Ch. 2.7 - Salary offers to MBAs. Consider the top salary...Ch. 2.7 - Prob. 2.115ACICh. 2.7 - Prob. 2.116ACICh. 2.7 - Sanitation inspection of cruise ships. Referto...Ch. 2.7 - Network server downtime. A manufacturer of network...Ch. 2.7 - Permeability of sandstone during weathering. Refer...Ch. 2.7 - Prob. 2.120ACACh. 2.7 - Prob. 2.121ACACh. 2.8 - Construct a scatterplot for the data in the...Ch. 2.8 - Construct a scatterplot for the data in the...Ch. 2.8 - Prob. 2.124ACBCh. 2.8 - Prob. 2.125ACBCh. 2.8 - Lobster trap placement. Strategic placement of...Ch. 2.8 - Does elevation impact hitting performance in...Ch. 2.8 - Prob. 2.128ACBCh. 2.8 - Prob. 2.129ACBCh. 2.8 - Spreading rate of spilled liquid A contract...Ch. 2.8 - Performance ratings of government agencies. The...Ch. 2.8 - Most valuable NFL teams. Refer to the Forbes...Ch. 2.8 - Best-paid CEOs. Refer to Glassdoor Economic...Ch. 2.8 - Prob. 2.134ACACh. 2.10 - Museum management. Refer to the Museum Management...Ch. 2.10 - Volkswagen emissions scandal. Refer to the...Ch. 2.10 - BP oil leak. In the summer of 2010, an explosion...Ch. 2 - Construet a relative frequency histogram for the...Ch. 2 - Discuss the conditions under which the median is...Ch. 2 - Consider the following three measurements: 50, 70,...Ch. 2 - Refer to Exercise 2.141c. For parts a-d, determine...Ch. 2 - For each of the following data sets, compute x,...Ch. 2 - For each of the following data sets, compute x,...Ch. 2 - Explain why we generally prefer the standard...Ch. 2 - If the range of a set of data is 20, find a rough...Ch. 2 - Prob. 2.147LMCh. 2 - Motivation of drug dealers. Refer to the Applied...Ch. 2 - Slogs for Fortune 500 firms. Web site...Ch. 2 - Management system failures. The U.S. Chemical...Ch. 2 - Business marketing publications....Ch. 2 - U.S. business bankruptcies. The American...Ch. 2 - Prob. 2.153ACBCh. 2 - Products Made in the USA. Made in the USA is a...Ch. 2 - Prob. 2.155ACBCh. 2 - Drivers stopped by police. According to the Bureau...Ch. 2 - U.S. wine export markets. The Center for...Ch. 2 - Prob. 2.158ACICh. 2 - Hull failures of oil tankers. Owing to several...Ch. 2 - Software defects. The Promise Software Engineering...Ch. 2 - Prob. 2.161ACICh. 2 - Time to develop price quotes. A manufacturer of...Ch. 2 - Trend in Iraq War casualties. While the United...Ch. 2 - Prob. 2.164ACICh. 2 - Radiation levels in homes. In some locations,...Ch. 2 - Doctors and ethics. For physicians confronted with...Ch. 2 - Prob. 2.167ACICh. 2 - Investigating the claims of weight-loss clinics....Ch. 2 - Age discrimination study. The Age Discrimination...Ch. 2 - No Child Left Behind Act. According to the...Ch. 2 - Steel rod quality. In his essay Making Things...
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