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About 102926 results. 1294 free access solutions
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| m102550 | The aim of a study in the article, "Separate and Joint Effects of Physical and Mental Health on Participation of People with Somatic Chronic Illness" (Journal of Nursing and Healthcare of Chronic Illness, Vol. 3, Issue 1, pp. 61- 72), by D. Jansen and M. Rijken, is to examine the extent to which people with a chronic illness participate in activities such as jobs, volunteer work, or other social activities. In the study, a sample of 1456 chronic illness patients resulted in the statistics provided in the following table. The first two columns of the table present a percentage distribution for the degree of urbanism of the respondent s home address; the third column gives the percentage of the respondents in each degree of urbanism category who participated in social activities such as sports, church, or clubs.
For one of these respondents selected at random, determine the probability that he or she
a. Participates in social activities.
b. Lives in an extremely urbanized environment, given that he or she participates in social activities.
c. Does not live in an extremely urbanized environment, given that he or she participates in social activities.
d. Interpret your answers in parts (a)-(c) in terms of percentages. |
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| m102551 | The Air Travel Consumer Report is a monthly product of the Department of Transportation s Office of Aviation Enforcement and Proceedings. The report is designed to assist consumers with information on the quality of services provided by the airlines. Following are the percentages of on-time arrivals for June 2013 by the 16 reporting airlines.
a. Identify the classes for grouping these data, using cutpoint grouping with classes of equal width 5 and a first lower class cutpoint of 60.
b. Identify the class midpoints of the classes found in part (a).
c. Construct frequency and relative-frequency distributions of the data based on your classes from part (a).
d. Draw a frequency histogram of the data based on your classes from part (a).
e. Round each observation to the nearest whole number, and then construct a stem-and-leaf diagram with two lines per stem.
f. Obtain the greatest integer in each observation, and then construct a stem-and-leaf diagram with two lines per stem.
g. Which of the stem-and-leaf diagrams in parts (e) and (f) corresponds to the frequency histogram in part (d)? Explain why. |
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| m102552 | The American Association of University Professors (AAUP) conducts salary studies of college professors and publishes its findings in AAUP Annual Report on the Economic Status of the Profession. Pairs were formed by matching faculty in private and public institutions by rank and specialty. A random sample of 30 pairs yielded the data, in thousands of dollars, presented on the WeissStats site. Use the technology of your choice to do the following.
a. Apply the paired Wilcoxon signed-rank test to decide, at the 5% significance level, whether the data provide sufficient evidence to conclude that mean salaries differ for faculty in private and public institutions.
b. Compare your result in part (a) to the one obtained in Exercise 10.170 on page 497, where the paired t-test was used.
c. Which test do you think is preferable: the paired t-test or the paired Wilcoxon signed-rank test? Explain your answer. |
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| m102553 | The American Enterprise Institute (AEI) Public Opinion Study found that 86% of Americans are satisfied with their job (AEI website, December 4, 2015). Is this consistent across age groups? A follow-up survey revealed that 72% of Americans age 18-30 are satisfied with their job, 85% of Americans age 31-50 are satisfied with their job, and 93% of Americans age 51-70 are satisfied with their job. Suppose that 200 workers were surveyed in each age group.
a. Construct a 95% confidence interval for the proportion of workers in each of these age groups who is satisfied with her or his job. Do these results surprise you? Why or why not?
b. Assuming the same sample size will be used in each age group, how large would the sample need to be to ensure that the margin of error is .05 or less for each of the three confidence intervals? |
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| m102554 | The American Hospital Association conducts annual surveys of hospitals in the United States and publishes its findings in AHA Hospital Statistics. Data on hospital type for U.S. registered hospitals can be found on the WeissStats site. For convenience, we use the following abbreviations:
NPC: Nongovernment not-for-profit community hospitals
IOC: Investor-owned (for-profit) community hospitals
SLC: State and local government community hospitals
FGH: Federal government hospitals
NFP: Nonfederal psychiatric hospitals
NLT: Nonfederal long-term-care hospitals
HUI: Hospital units of institutions
Use the technology of your choice to obtain the measures of center that are appropriate from among the mean, median, and mode. Discuss your results and decide which measure of center is most appropriate. Provide a reason for your answer. |
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| m102555 | The American Potato Growers Association (APGA) would like to test the claim that the proportion of fast food orders this year that includes French fries exceeds the proportion of fast food orders that included French fries last year. Suppose that a random sample of 49,581 electronic receipts for fast food orders placed this year shows that 31,038 included French fries. Assuming that the proportion of fast food orders that included French fries last year is .62, use this information to test APGA s claim at α = .05. Discuss the practical significance of the results. |
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| m102556 | The American Press Institute reports that almost 70% of all American adults use a computer to gain access to news. Suppose you suspect that the proportion of American adults under 30 years old who use a computer to gain access to news exceeds the proportion of Americans at least 30 years old who use a computer to gain access to news. Data in the file ComputerNews represent responses to the question "Do you use a computer to gain access to news?" given by random samples of American adults under 30 years old and Americans who are at least 30 years old.
a. Estimate the proportion of American adults under 30 years old who use a computer to gain access to news and the proportion of Americans at least 30 years old who use a computer to gain access to news.
b. Provide a 95% confidence interval for the difference in these proportions.
c. O n the basis of your findings, does it appear the proportion of American adults under 30 years old who use a computer to gain access to news exceeds the proportion of Americans who are at least 30 years old that use a computer to gain access to news? |
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| m102557 | The American Time Use Study is a survey of people in the United States regarding the amount of time they spend on various activities in a typical day. On a given day, 22% of American men participate in sports, exercise, or recreation. On days they participated in these activities, men participated on average 1.8 hours in sports, exercise, or recreation (Bureau of Labor Statistics website, December 2015). Suppose that the time spent on sports, exercise, and recreation for men on days of participation is distributed exponentially.
a. What is the probability that when a man participates in sports, exercise, or recreation, he does so for less than or equal to 1 hour?
b. What is the probability that when a man participates in sports, exercise, or recreation, he does so for more than 2 hours? |
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| m102558 | The amount of money spent weekly on cleaning, maintenance, and repairs at a large restaurant was observed over a long period of time to be approximately normally distributed, with mean ( = $615 and standard deviation ( = $42.
(a) If $646 is budgeted for next week, what is the probability that the actual costs will exceed the budgeted amount?
(b) Inverse Normal Distribution How much should be budgeted for weekly repairs, cleaning, and maintenance so that the probability that the budgeted amount will be exceeded in a given week is only 0.10? |
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| m102559 | The amount of solar energy transmitted through each square meter of space prior to entry in the earth s atmosphere, as measured by satellites, is called the total solar irradiance (TSI). A random sample of daily TSI measurements, in watts per square meter, from the World Radiation Center in Switzerland is as follows. |
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| m102560 | The annual update of U.S. Overseas Loans and Grants, informally known as the "Greenbook," contains data on U.S. government monetary economic and military assistance loans. The following table shows military assistance loans, in thousands of dollars, to a sample of 10 countries, as reported by the U.S. Agency for International Development.
In each of Exercises 8.135-8.138, use the technology of your choice to decide whether applying the t-interval procedure to obtain a confidence interval for the population mean in question appears reasonable. Explain your answers. |
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| m102561 | The annual update of U.S. Overseas Loans and Grants, informally known as the "Greenbook," contains data on U.S. government monetary economic and military assistance loans. The following table shows military assistance loans, in thousands of dollars, to a sample of 10 countries, as reported by the U.S. Agency for International Development. |
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| m102562 | The article "Study Links Hepatitis B and Cancer of Pancreas" by D. Grady, appeared in the September 29, 2008 issue of the NewYork Times. It reported that, for the first time, a study showed that people with pancreatic cancer are more likely than those without the disease to have been infected with the hepatitis B virus. The study by M. Hassan et al., titled "Association between Hepatitis B Virus and Pancreatic Cancer" (Journal of Clinical Oncology, Vol. 26, No. 28, pp. 4557-4562) compared 476 people who had pancreatic cancer with 879 healthy control subjects. All were tested to see whether they had ever been infected with the viruses that cause hepatitis B or hepatitis C. The results were that no connection was found to hepatitis C, but the cancer patients were twice as likely as the healthy subjects to have had hepatitis B. The researchers noted, however, that ". . . while the study showed an association, it did not prove cause and effect. More work is needed to determine whether the virus really can cause pancreatic cancer." Explain the validity of the statement in quotes. |
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| m102563 | The Association of American Medical Colleges (AAMC) compiles data on medical school faculty and publishes the results in AAMC Faculty Roster. The following table presents a frequency distribution of rank for medical school faculty during one year.
Rank ____________________________ Frequency
Professor .................................... 32,511
Associate professor ........................ 28,572
Assistant professor ........................ 59,277
Instructor .................................... 14,289
Other ......................................... 3,276
a. Obtain a relative-frequency distribution.
b. Draw a pie chart.
c. Construct a bar chart. |
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| m102564 | The Association of American Medical Colleges (AAMC) compiles data on active U.S. physicians and publishes its results in the Physician Specialty Data Book. From that document, 13.6% of active U.S. physicians specialize in internal medicine and 8.67% of active U.S. physicians are under age 55 and specialize in internal medicine. What percentage of active U.S. physicians who specialize in internal medicine are under age 55? |
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| m102565 | The Association of American Medical Colleges (AAMC) compiles data on medical school faculty and publishes the results in AAMC Faculty Roster. The following table presents a frequency distribution of rank for medical school faculty during one year.
Rank Frequency
Professor ................ 32,511
Associate professor ........... 28,572
Assistant professor .......... 59,277
Instructor ..................... 14,289
Other ........................ 3,276
a. Determine the mode of the data.
b. Decide whether it would be appropriate to use either the mean or the median as a measure of center. Explain your answer. |
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| m102566 | The Association of American Medical Colleges (AAMC) compiles data on medical school faculty and publishes the results in AAMC Faculty Roster. The following contingency table cross-classifies medical school faculty by the characteristics gender and rank.
a. Find P(R3).
b. Find P(R3 | G1).
c. Are events G1 and R3 independent? Explain your answer.
d. For a medical school faculty member, is the event that the person is female independent of the event that the person is an associate professor? Explain your answer. |
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| m102567 | The Association of American Universities published a report titled "Looking More Closely at Student Debt." This report explores the issue about the cost of a college education and its impact on student loan debt. Using information from a credit reporting company, the following table provides a percentage distribution for the loan balance of outstanding student loans from individuals with graduate, professional, and undergraduate degree debt.
Loan balance _____________________Percentage
$1-$10,000 ................................ 43.1
$10,001-$25,000 ......................... 29.2
$25,001-$50,000 ......................... 16.5
$50,001-$75,000 ......................... 5.8
$75,001-$100,000 ........................ 2.3
$100,001 or more ......................... 3.1
Suppose that one of these individuals is selected at random.
a. Without using the general addition rule, determine the probability that the individual obtained has a loan balance either between $10,001 and $100,000, inclusive, or at most $75,000.
b. Obtain the probability in part (a) by using the general addition rule. |
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| m102568 | The Atlantic Hurricane Database extends back to 1851, recording among other things the number of major hurricanes striking the U.S. Atlantic and Gulf Coast per year. A major hurricane is a hurricane measuring at least a Category 3 on the Saffir-Simpson hurricane wind scale (i.e., with winds of at least 110 mph). As published by the National Oceanic & Atmospheric Administration and the Atlantic Oceanographic & Meteorological Laboratory, the following table provides a probability distribution for the number of major hurricanes, Y , for a randomly selected year between 1851 and 2012.
Use random-variable notation to represent each of the following events. The year had
a. At least one major hurricane.
b. Exactly three major hurricanes.
c. Between 2 and 4 major hurricanes, inclusive.
Use the special addition rule and the probability distribution to determine
d. P(Y ≥ 1).
e. P(Y = 3).
f. P(2 ≤ Y ≤ 4). |
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| m102569 | The author spoke with a representative of the U.S. Postal Service and obtained the following information about zip codes. A five-digit zip code consists of five digits, of which the first three give the sectional center and the last two the post office or delivery area. In addition to the five-digit zip code, there is a trailing plus four zip code. The first two digits of the plus four zip code give the sector or several blocks and the last two the segment or side of the street. For the five-digit zip code, the first four digits can be any of the digits 0-9 and the fifth any of the digits 1-8. For the plus four zip code, the first three digits can be any of the digits 0-9 and the fourth any of the digits 1-9.
a. How many possible five-digit zip codes are there?
b. How many possible plus four zip codes are there?
c. How many possibilities are there in all, including both the five digit zip code and the plus four zip code? |
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