New Semester
Started
Get
50% OFF
Study Help!
--h --m --s
Claim Now
Question Answers
Textbooks
Find textbooks, questions and answers
Oops, something went wrong!
Change your search query and then try again
S
Books
FREE
Study Help
Expert Questions
Accounting
General Management
Mathematics
Finance
Organizational Behaviour
Law
Physics
Operating System
Management Leadership
Sociology
Programming
Marketing
Database
Computer Network
Economics
Textbooks Solutions
Accounting
Managerial Accounting
Management Leadership
Cost Accounting
Statistics
Business Law
Corporate Finance
Finance
Economics
Auditing
Tutors
Online Tutors
Find a Tutor
Hire a Tutor
Become a Tutor
AI Tutor
AI Study Planner
NEW
Sell Books
Search
Search
Sign In
Register
study help
business
business statistics
Statistics Concepts And Controversies 7th Edition David S Moore, William I Notz - Solutions
Web-based exercise. The online version of the newspaper The Independent has an interesting story concerning the use of “anonymised”information in a legal case. Visit the Web page, news.independent.co.uk/uk/crime/article101735.ece/, and read the article. The article seems to refer to the study
Decency and public money. Congress has often objected to spending public money on projects that seem “indecent” or “in bad taste.” The arts are most often affected, but science can also be a target. Congress once refused to fund an experiment to study the effect of marijuana on sexual
Tempting subjects. A psychologist conducts the following experiment:she measures the attitude of subjects toward cheating, then has them play a game rigged so that winning without cheating is impossible. The computer that organizes the game also records—unknown to the subjects—whether or not
Deceiving subjects. Students sign up to be subjects in a psychology experiment. When they arrive, they are told that interviews are running late and are taken to a waiting room. The experimenters then stage a theft of a valuable object left in the waiting room. Some subjects are alone with the
Surveys of youth. The Centers for Disease Control and Prevention, in a survey of teenagers, asked the subjects if they were sexually active. Those who said “Yes” were then asked, “How old were you when you had sexual intercourse for the first time?” Should consent of parents be required to
Charging for data? Data produced by the government are often available free or at low cost to private users. For example, satellite weather data produced by the U.S. National Weather Service are available free to TV stations for their weather reports and to anyone on the Web. Opinion 1: Government
Telling the government. The 2000 census long form asked 53 detailed questions, for example:Do you have COMPLETE plumbing facilities in this house, apartment, or mobile home; that is, 1) hot and and cold piped water, 2) a flush toilet, and 3) a bathtub or shower?The form also asked your income in
A right to know? Some people think that the law should require that all political poll results be made public. Otherwise, the possessors of poll results can use the information to their own advantage. They can act on the information, release only selected parts of it, or time the release for best
Opinion polls. The presidential election campaign is in full swing, and the candidates have hired polling organizations to take regular polls to find out what the voters think about the issues. What information should the pollsters be required to give out?(a) What does the standard of informed
AIDS trials in Africa. One of the most important goals of AIDS research is to find a vaccine that will protect against HIV. Because AIDS is so common in parts of Africa, that is the easiest place to test a vaccine. It is likely, however, that a vaccine would be so expensive that it could not (at
AIDS trials in Africa. Effective drugs for treating AIDS are very expensive, so most African nations cannot afford to give them to large numbers of people. Yet AIDS is more common in parts of Africa than anywhere else. A few clinical trials are looking at ways to prevent pregnant mothers infected
AIDS clinical trials. Now that effective treatments for AIDS are at last available, is it ethical to test treatments that may be less effective? Combinations of several powerful drugs reduce the level of HIV in the blood and at least delay illness and death from AIDS. But effectiveness depends on
Sham surgery? Clinical trials like the Parkinson’s disease study mentioned in Example 6 are becoming more common. One medical researcher says,“This is just the beginning. Tomorrow, if you have a new procedure, you will have to do a double-blind placebo trial.” Example 6 outlines the arguments
Equal treatment. Researchers on aging proposed to investigate the effect of supplemental health services on the quality of life of older people. Eligible patients on the rolls of a large medical clinic were to be randomly assigned to treatment and control groups. The treatment group would be
Human biological materials. Long ago, doctors drew a blood specimen from you as part of treating minor anemia. Unknown to you, the sample was stored. Now researchers plan to use stored samples from you and many other people to look for genetic factors that may influence anemia. It is no longer
Not really anonymous. Some common practices may appear to offer anonymity while actually delivering only confidentiality. Market researchers often use mail surveys that do not ask the respondent’s identity but contain hidden codes on the questionnaire that identify the respondent. A false claim
Anonymous or confidential? A Web site looking for volunteers for a research study contains the following information. “This is a research study about menstruation. People of all ages may participate in this study. This questionnaire will take only a few minutes to complete and it’s anonymous.
Anonymous or confidential? The University of Wisconsin at Madison, like many universities, offers free screening for HIV, the virus that causes AIDS. The announcement says that for persons who come for testing, “A code is used instead of your own name. You receive a copy of the report for your
Anonymous or confidential? One of the most important nongovernment surveys in the United States is the General Social Survey (see Example 7 in Chapter 1). The GSS regularly monitors public opinion on a wide variety of political and social issues. Interviews are conducted in person in the
How common is HIV infection? Researchers from Yale University, working with medical teams in Tanzania, wanted to know how common infection with the AIDS virus is among pregnant women in that African country.To do this, they planned to test blood samples drawn from pregnant women.Yale’s
Students as subjects. Students taking Psychology 001 are required to serve as experimental subjects. Students in Psychology 002 are not required to serve, but they are given extra credit if they do so. Students in Psychology 003 are required either to sign up as subjects or to write a term paper.
Is consent needed? In which of the circumstances below would you allow collecting personal information without the subjects’ consent?(a) A government agency takes a random sample of income tax returns to obtain information on the average income of people in different occupations.Only the incomes
Informed consent. A researcher suspects that ultraconservative political beliefs tend to be associated with an authoritarian personality. She prepares a questionnaire that measures authoritarian tendencies and also asks many political questions. Write a description of the purpose of this research
Institutional review boards. If your college or university has an institutional review board that screens all studies that use human subjects, get a copy of the document that describes this board (you can probably find it online).At larger institutions you may find multiple institutional review
Who serves on the review board? Government regulations require that institutional review boards consist of at least five people, including at least one scientist, one nonscientist, and one person from outside the institution. Most boards are larger, but many contain just one outsider.(a) Why should
Minimal risk? You are a member of your college’s institutional review board. You must decide whether several research proposals qualify for less rigorous review because they involve only minimal risk to subjects. Federal regulations say that “minimal risk” means the risks are no greater than
Anonymous or confidential? A university offers screening for sexually transmitted diseases. The announcement says, “Persons who sign up for screening will be assigned a number so that they do not have to give their name.” They can learn the results of the test by telephone, still without giving
Informed consent? A 72-year-old man with multiple sclerosis is hospitalized. His doctor feels he may need to be placed on a feeding tube soon to ensure adequate nourishment. He asks the patient about this in the morning and the patient agrees. However, in the evening (before the tube has been
Web-based exercise. Find an example of a variable, such as the price of a commodity, that is changing over time. One possible source is the Bureau of Labor Statistics Web site. Go to www.bls.gov/cpi/home.htm and click on the Average Price Data link.
Web-based exercise. Find an example of a poor graphic. One possible source is the CHANCE Web site at Dartmouth College. In particular, the Chance News section, www.dartmouth.edu/~chance/chance news/news.html, offers a monthly newsletter that includes graphics.
The Boston Marathon. Women were allowed to enter the Boston Marathon in 1972. The time (in minutes, rounded to the nearest minute) for each winning woman from 1972 to 2007 appears in Table 10.4.(a) Make a graph of the winning times.(b) Give a brief description of the pattern of Boston Marathon
Yields of money market funds. Many people invest in money market funds. These are mutual funds that attempt to maintain a constant price of $1 per share while paying monthly interest. Table 10.3 gives the average annual interest rates (in percent) paid by all taxable money market funds since 1973,
Accidental deaths. In 2004 there were 112,012 deaths from accidents in the United States. Among these were 44,933 deaths from motor vehicle accidents, 20,950 from poisoning, 3308 from drowning, 3229 from fires, and 649 from firearms.(a) Find the percentage of accidental deaths from each of these
Bad habits. According to the National Household Survey on Drug Abuse, 40.4% of adolescents aged 12 to 17 years used alcohol in 2006, 17.3% used marijuana, 2.2% used cocaine, and 25.8% used cigarettes. Explain why it is not correct to display these data in a pie chart.
Sketch line graphs of a series of observations over time having each of these characteristics. Mark your time axis in years.(a) A strong downward trend, but no seasonal variation.(b) Seasonal variation each year, but no clear trend.(c) A strong downward trend with yearly seasonal variation.
The Border Patrol. Here are the numbers of deportable aliens caught by the U.S. Border Patrol for 1971 through 2005. Display these data in a graph.What are the most important facts that the data show?Year: 1971 1973 1975 1977 1979 1981 1983 1985 1987 Count (1000s): 420 656 767 1042 1076 976 1251
Who sells cars? Make a bar graph of the data in Exercise 10.21. What advantage does your new graph have over the pie chart in Figure 10.18?
The sunspot cycle. Some plots against time show cycles of up-anddown movements. Figure 10.17 is a line graph of the average number of sunspots on the sun’s visible face for each month from 1900 to 2007. What is the approximate length of the sunspot cycle? That is, how many years are there between
Counting employed people. A news article says:More people were working in America in June than in any month since the end of 1990. If that’s not what you thought you read in the papers last week, don’t worry. It isn’t. The report that employment plunged in June, with nonfarm payrolls
Sales are up. The sales at your new gift shop in December are double the November value. Should you conclude that your shop is growing more popular and will soon make you rich? Explain your answer.
Seasonal variation. You examine the average temperature in Chicago each month for many years. Do you expect a line graph of the data to show seasonal variation?Describe the kind of seasonal variation you expect to see.
Trends. Which of these series of data do you expect to show a clear trend? Will the trend be upward or downward?(All data are recorded annually.)(a) The percentage of students entering a university who bring a typewriter with them.(b) The percentage of students entering a university who bring a
Births to unwed mothers. Here are data on births to unwed mothers as a percentage of births in the United States, from the Statistical Abstract.These data show a clear increasing trend over time. Make two line graphs of these data: one designed to show only a gradual increase over time, and a
Civil disorders. The years around 1970 brought unrest to many U.S.cities. Here are government data on the number of civil disturbances in each 3-month period during the years 1968 to 1972.Period Count Period Count 1968, Jan.–Mar. 6 1970, July–Sept. 20 Apr.– June 46 Oct.–Dec. 6 July–Sept.
College freshmen. A survey of college freshmen in 2001 asked what field they planned to study. The results: 12.6%, arts and humanities; 16.6%, business; 10.1%, education; 18.6%, engineering and science; 12.0%, professional;and 10.3%, social science.(a) What percentage of college freshmen plan to
Murder weapons. The 2008 Statistical Abstract of the United States reports FBI data on murders for 2005. In that year, 50.5% of all murders were committed with handguns, 17.3% with other firearms, 12.8% with knives, 6.0%with a part of the body (usually the hands or feet), and 4.1% with blunt
Marital status. In the U.S. Census Bureau document America’s Families and Living Arrangements: 2006, we find these data on the marital status of American women 15 years and older as of 2006:Marital status Count (thousands)Never married 31,429 Married 61,217 Widowed 11,290 Divorced 13,127(a) How
Consistency? Table 10.2 shows how Indiana state lottery sales are divided among different types of games. What is the sum of the amounts spent on the nine types of games? Why is this sum not exactly equal to the total given in the table?
Lottery sales. States sell lots of lottery tickets. Table 10.2 shows where the money comes from in the state of Indiana. Make a bar graph that shows the distribution of lottery sales by type of game. Is it also proper to make a pie chart of these data? Explain.TABLE 10.2 Indiana state lottery sales
The price of milk. The U.S. Department of Agriculture Web site provides data on the monthly average price of a gallon of whole milk. The following table gives the values for 2006 and 2007.Date Price ($) Date Price ($)1/06 3.30 1/07 3.29 2/06 3.26 2/07 3.29 3/06 3.25 3/07 3.31 4/06 3.23 4/07 3.32
Taxes. The Retirement Living Information Center compiled data on projected combined state and local taxes as a percentage of income for each of the 50 states for 2007. The table below gives the values for some selected midwestern states.State Tax as percentage of income Illinois 10.8%Indiana 10.7
An implausible number? Newsweek once said in a story that a woman who is not currently married at age 40 has a better chance of being killed by a terrorist than of getting married. Do you think this is plausible? What kind of data would help you check this claim?
Percentage decrease. On Monday, September 10, 2001 (the day before the September 11 attacks), the NASDAQ stock index closed the day at 1695. By the end of Monday, September 17, 2001 (the first full day of trading after the attacks), the NASDAQ stock index had dropped to 1580. By what percentage did
Percents up and down. Between March 2007 and June 2007 the average price of regular gasoline increased from $2.40 per gallon to $3.00 per gallon.(a) Verify that this is a 25% increase in price.(b) If the price of gasoline decreases by 25% from its June level of $3.00 per gallon, what would be the
Observation or experiment? In a study of the relationship between physical fitness and personality, middle-aged college faculty who have volunteered for an exercise program are divided into low-fitness and high-fitness groups on the basis of a physical examination. All subjects then take a
Observation or experiment? The Nurses’ Health Study has queried a sample of over 100,000 female registered nurses every two years since 1976.Beginning in 1980, the study asked questions about diet, including alcohol consumption. The researchers concluded that “light-to-moderate drinkers had a
Reliability. You are laboring through a chemistry laboratory assignment in which you measure the conductivity of a solution. What does it mean for your measurement to be reliable? How can you improve the reliability of your final result? (Hint: See pages 151–155.)
Measuring. Joni wants to measure the degree to which male college students belong to the political left. She decides simply to measure the length of their hair—longer hair will mean more left-wing.(a) Is this method likely to be reliable? Why?(b) This measurement appears to be invalid. Why?(c)
Ethics. What are the three first principles of data ethics? Explain briefly what the flu vaccine study must do to apply each of these principles. (Hint: See pages 123–128.)
Design an experiment. Use a diagram to outline the design of the experiment in this medical study.Part I Review Exercises 187
Experiment basics. Identify the subjects, the explanatory variable, and several response variables for this study. (Hint: See pages 81–83.)
Know these terms. Explain in one sentence each what “randomized,”“double-blind,” and “placebo-controlled” mean in the description of the design of the study.
Design an experiment. Gary thinks that the way to get a date is to tell a woman about yourself. Greg thinks that getting her to talk about herself works better. You recruit 20 guys who are willing to try either method in conversation and then call the woman a day later to ask for a date. Outline
Design an experiment. A university’s Department of Statistics wants to attract more majors. It prepares two advertising brochures. Brochure A stresses the intellectual excitement of statistics. Brochure B stresses how much money statisticians make. Which will be more attractive to first-year
What kind of sample? At a party there are 30 students over age 21 and 20 students under age 21. You choose at random 3 of those over 21 and 186 Part I Review separately choose at random 2 of those under 21 to interview about attitudes toward alcohol. You have given every student at the party the
Find the margin of error. Should the commissioner of baseball punish Major League Baseball players named in the Mitchell report on steroid use in baseball for having used steroids? A poll of 413 professional baseball fans found that 248 said “Yes.”(a) What is the population for this sample
Find the margin of error. On September 7, 2007, 384 professional golf fans were asked “Do you think that, as a result of becoming a father, Tiger Woods’s golf game will improve, not be affected, or will get worse?” In all, 70%said “not be affected.”(a) What is the population for this
Errors in surveys. A Gallup Poll found that 30% of adult Americans claim to have postponed medical treatment due to cost. The Gallup press release says:Results are based on telephone interviews with 1,014 national adults, aged 18 and older, conducted Nov. 11–14, 2007. For results based on the
Errors in surveys. Exercises I.7 and I.8 each mention a source of error in a sample survey. Would each kind of error be reduced by doubling the size of the sample with no other changes in the survey procedures? Explain your answers. (Hint: See pages 41–43 and 58–63.)
Errors in surveys. A college chooses an SRS of 100 students from the registrar’s list of all undergraduates to interview about student life. If it selected two SRSs of 100 students at the same time, the two samples would give somewhat different results. Is this variation a source of sampling
Errors in surveys. An overnight opinion poll calls randomly selected telephone numbers. This polling method misses all people without a phone.Part I Review Exercises 185 Is this a source of nonsampling error or of sampling error? Does the poll’s announced margin of error take this source of error
Errors in surveys. Give an example of a source of nonsampling error in a sample survey. Then give an example of a source of sampling error.
Select an SRS. The faculty grievance system at a university specifies that a 5-member hearing panel shall be drawn at random from the 30-member grievance committee. Use Table A at line 107 to draw an SRS of size 5 from the following committee members.Ajayi Frazier Lam Salwan Walters Berrett Gordon
Select an SRS. A student at a large university wants to study the responses that students receive when calling an academic department for information.She selects an SRS of 6 departments from the following list for her study. Use Table A at line 116 to do this.Agronomy Education Natural Resources
A biased sample. You see a woman student standing in front of the student center, now and then stopping other students to ask them questions.She says that she is collecting student opinions for a class assignment.Explain why this sampling method is almost certainly biased. (Hint: See page 22.)
Know these terms. A friend who knows no statistics has encountered some statistical terms in her biology course. Explain each of the following terms in one or two simple sentences.(a) Observational study.(b) Placebo effect.(c) Statistically significant.(d) Institutional review board.
Know these terms. A friend who knows no statistics has encounteredsome statistical terms in reading for her psychology course. Explain each of the following terms in one or two simple sentences.(a) Simple random sample. (Hint: See page 24.)(b) 95% confidence. (Hint: See page 44.)(c) Nonsampling
Web-based exercise. Money magazine annually publishes a list of its best places to live. You can find the 2007 rankings online at money.cnn.com/magazines/moneymag/bplive/2007/. Read how the rankings are determined at money.cnn.com/magazines/moneymag/bplive/2007/faq/ and give five variables that are
Web-based exercise. You can get the time direct from the atomic clock at NIST at www.time.gov. There is some error due to Internet delays, but the display even tells you roughly how accurate the time on the screen is. Look up the time for your state. What is the reported accuracy?AppendixLO1
Web-based exercise. Each year, U.S. News & World Report ranks the nation’s colleges and universities. You can find the current rankings on the magazine’s Web site, www.usnews.com. Colleges often dispute the validity of the rankings, and some even say that U.S. News changes its measurement
Where to live? Each year, Forbes magazine ranks the 150 largest metropolitan areas in the United States in an article on the best places for business. Second place in 2007 went to Provo, Utah. Provo was ranked 27th in 2006 and 15th in 2005. TheWashington, DC–northern Virginia metropolitan area
The best earphones. You are writing an article for a consumer magazine based on a survey of the magazine’s readers that asked about satisfaction with inexpensive earphones for the iPod. Of 1317 readers who reported owning the Apple iPod earphones, 237 gave it an outstanding rating. Only 25
Testing job applicants. A company used to give IQ tests to all job applicants. This is now illegal because IQ is not related to the performance of workers in all the company’s jobs. Does the reason for the policy change involve the reliability, the bias, or the validity of IQ tests as a measure
Tough course? A friend tells you, “In the 7:30 A.M. lecture for Statistics 101, 9 students failed, but 20 students failed in the 1:30 P.M. lecture. The 7:30 A.M. prof is a tougher grader than the 1:30 P.M. teacher.” Explain why the conclusion may not be true. What additional information would
Measuring pulse rate. You want to measure your resting pulse rate.You might count the number of beats in 6 seconds and multiply by 10 to get beats per minute. Why is this method less reliable than actually measuring the number of beats in a minute?AppendixLO1
Measuring crime. Twice each year, the National Crime Victimization Survey asks a random sample of about 49,000 households whether they have been victims of crime and, if so, the details. In all, nearly 100,000 people answer these questions. If other people in a household are in the room while one
Measuring crime. Crime data make headlines.We measure the amount of crime by the number of crimes committed or (better) by crime rates (crimes per 100,000 population). The FBI publishes data on crime in the United States by compiling crimes reported to police departments. The FBI data are recorded
A recipe for poor reliability. Every month, the government releases data on “personal savings.” This number tells us how many dollars individuals saved the previous month. Savings are calculated by subtracting personal spending (an enormously large number) from personal income (another enormous
Does job training work? To measure the effectiveness of government training programs, it is usual to compare workers’ pay before and after training.But many workers sign up for training when their pay drops or they are laid off. So the “before” pay is unusually low and the pay gain looks
More on bias and reliability. The previous exercise gives 5 true values for lengths. A subject measures each length twice by eye. Make up a set of results from this activity that matches each of the descriptions below.For simplicity, assume that bias means the same fixed error every time rather
An activity on bias and reliability. Cut 5 pieces of string having these lengths in inches: 2.9 9.5 5.7 4.2 7.6(a) Show the pieces to another student one at a time, asking the subject to estimate the length to the nearest tenth of an inch by eye. The error your subject makes is measured value minus
An activity on bias. Let’s study bias in an intuitive measurement.Figure 8.3 is a drawing of a tilted glass. Reproduce this drawing on 10 sheets of paper. Choose 10 people: 5 men and 5 women. Explain that the drawing represents a tilted glass of water. Ask each subject to draw the water level
Validity, bias, reliability. Give your own example of a measurement process that is valid but has large bias. Then give your own example of a measurement process that is invalid but highly reliable.AppendixLO1
Testing job applicants. The law requires that tests given to job applicants must be shown to be directly job related. The Department of Labor believes that an employment test called the General Aptitude Test Battery(GATB) is valid for a broad range of jobs. As in the case of the SAT, blacks and
Fighting cancer. Congress wants the medical establishment to show that progress is being made in fighting cancer. Here are some variables that might be used:1. Total deaths from cancer. These have risen sharply over time, from 331,000 in 1970, to 505,000 in 1990, and to 553,888 in 2004.2. The
Measuring pain. The Department of Veterans Affairs offers medical care to 5.5 million patients. It wants doctors and nurses to treat pain as a “fifth vital sign,” to be recorded along with blood pressure, pulse, temperature, and breathing rate. Help out the VA: how would you measure a
Measuring life’s quality. Is life in Britain getting better or worse? The usual government data don’t say. So the British government announced that it wants to add measures of such things as housing, traffic, and air pollution.“The quality of life is not simply economic,” said a deputy
Measuring intelligence. “Intelligence” means something like “general problem-solving ability.” Explain why it is not valid to measure intelligence by a test that asks questions such as Who wrote “The Star-Spangled Banner” ?Who won the last soccer World Cup?AppendixLO1
Capital punishment. Between 1976 and 2007, 1099 convicted criminals were put to death in the United States. Here are data on the number of executions in several states during those years, as well as the 2006 population of these states:Population State (thousands) Executions Alabama 4,599 38
Rates versus counts. Customers returned 36 coats to Sears this holiday season, and only 12 to La Boutique Classique next door. Sears sold 1200 coats this season, while La Boutique sold 200.(a) Sears had a greater number of coats returned. Why does this not show that Sears’s coat customers were
Showing 1400 - 1500
of 8575
First
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
Last
Step by Step Answers
Get 50% OFF
Claim Now
