Women diagnosed with breast cancer whose tumors have not spread may be faced with a decision between two surgical treatments—mastectomy (removal of the breast) or lumpectomy (only the tumor is removed). In a long-term study of the effectiveness of these two treatments, 701 women with breast cancer were randomly assigned to one of two treatment groups. One group received mastectomies, and the other group received lumpectomies and radiation. Both groups were followed for 20 years after surgery. It was reported that there was no statistically significant difference in the proportion surviving for 20 years for the two treatments (Associated Press, October 17, 2002). Suppose that this conclusion was based on a 90% confidence interval for the difference in treatment proportions. Which of the following three statements is correct? Explain why you chose this statement. Statement 1: Both endpoints of the confidence interval were negative. Statement 2: The confidence interval included 0. Statement 3: Both endpoints of the confidence interval were positive.
> A county commissioner must vote on a resolution that would commit substantial resources to the construction of a sewer in an outlying residential area. Her fiscal decisions have been criticized in the past, so she decides to take a survey of residents in
> At one point during the 2015 NFL season, Head Coach Bill Belichick and the New England Patriots had won 19 of their past 25 called coin flips at the beginning of NFL games (“for bill belichick, patriots’ strategy is no flip of the coin,” www.bostonglobe.
> Recall that in Exercise 10.63, a survey of 304 U.S. businesses found that 201 indicated that they monitor employees’ website visits. This data was used to determine if there is convincing evidence that a majority of businesses monitor e
> Data from a large study carried out in 2008 was used to estimate that 10% of all smokers who quit smoking are smoking again after one year (“relapse to Smoking after 1 Year of abstinence: a meta-analysis,” www.ncbi.nlm
> A sample of dogs were trained using a “Do as I do” method, in which the dog observes the trainer performing a simple task (such as climbing onto a chair or touching a chair) and is expected to perform the same task on the command “Do it!” In a separate t
> A study of treatment of hospitalized patients who develop pneumonia reported that 1 in 5 (20%) are readmitted to the hospital within 30 days after discharge (“comparison of therapist-Directed and physician-Directed respiratory care in c
> We are only beginning to learn about the longterm effects of space travel on human health. A study published in 2016 (Nature Scientific Reports 6, article number: 29901, www.nature.com/articles/srep29901, July 28, 2016, retrieved may 6, 2017) found that
> The article titled “13% of Americans Don’t Use the internet. who are they?” describes a study conducted by the pew research center (pewrearch.org, September 7, 2016, retrieved December 1, 2016). Suppose that the title of this article is based on a repres
> The survey described in the previous exercise also noted that of the 965 people that had checked their credit report within the last 12 months, 38% had done so as part of their regular financial planning. Does this provide convincing evidence that more t
> In 2016, the national foundation for credit counseling released a report titled “the 2016 consumer financial Literacy Survey” (www.nfcc.org, retrieved December 1, 2016). In a nationally representative sample of 1668 adult Americans, 965 indicated that th
> A number of initiatives on the topic of legalized gambling have appeared on state ballots. A political candidate has decided to support legalization of casino gambling if he is convinced that more than two-thirds of American adults approve of casino gamb
> The article “facebook Use and academic performance among college Students” (Computers in Human Behavior [2015]: 265–272) estimated that 87% percent of students at a large public university in California who are Facebook users update their status at least
> In a representative sample of adult Americans ages 26 to 32 years, 27% indicated that they owned a fitness band that kept track of the number of steps walked each day and their daily activity levels (“Digital Democracy Survey”, Deloitte Development LLc,
> According to a large national survey conducted by the Pew Research Center (“what americans think about nSa Surveillance, national Security and privacy,” may 2, 2015, www.pewresearch.org, retrieved December 1, 2016), 54% of adult Americans disapprove of t
> In a survey of 1000 women age 22 to 35 who work full-time, 540 indicated that they would be willing to give up some personal time in order to make more money (USA TODAY, march 4, 2010). The sample was selected to be representative of women in the targete
> In a survey conducted by CareerBuilder.com, employers were asked if they had ever fired an employee for holiday shopping online while at work (“cyber Monday Shopping at work? You’re not alone,” November 22, 2016, retrieved November 30, 2016). Of the 2379
> The report “a crisis in civic education” (American council of trustees and alumni, January 2016 www.goacta.org /images/download/a_crisis_in_civic_education.pdf, retrieved November 30, 2016) summarizes data from a survey of a representative sample of 100
> Duck hunting in populated areas faces opposition on the basis of safety and environmental issues. In a survey to assess public opinion regarding duck hunting on Morro Bay (located along the central coast of California), a random sample of 750 local resid
> The report “2007 electronic monitoring and Surveillance Survey: many companies monitoring, recording, Videotaping—and firing—employees” (american management association, 2007) summarized a survey of 304 U.S. businesses. Of these companies, 201 indicated
> A representative sample of 1000 likely voters in the United States included 440 who indicated that they think that women should not be required to register for the military draft (“most women oppose having to register for the Draft,” www .rasmessenreport
> Assuming a random sample from a large population, for which of the following null hypotheses and sample sizes is the large-sample z test appropriate? a. H0: p = 0.8, n = 40 b. H0: p = 0.4, n = 100 c. H0: p = 0.1, n = 50 d. H0: p = 0.05, n = 750
> Let p denote the proportion of students living on campus at a large university who plan to move off campus in the next academic year. For a large sample z test of H0: p = 0.70 versus Ha: p > 0.70, find the P-value associated with each of the following va
> Refer to the instructions given prior to Exercise 10.57. The paper referenced in the previous exercise also reported that when each of the 1178 students who participated in the study was asked if he or she played video games at least once a day, 271 resp
> The paper “pathological Video-game Use among Youth ages 8 to 18: a national Study” (Psychological Science [2009]: 594–601) summarizes data from a random sample of 1178 students age 8 to 18. The paper
> Refer to the instructions given prior to this exercise. The paper “college Students’ Social networking experiences on facebook” (Journal of Applied Developmental Psychology [2009]: 227â€
> In a survey of 1005 adult Americans, 46% indicated that they were somewhat interested or very interested in having web access in their cars (USA TODAY, may 1, 2009). Suppose that the marketing manager of a car manufacturer claims that the 46% is based on
> The report “Digital Democracy Survey” (Deloitte Development LLc, 2016, www2.deloitte.com/us/en.html, retrieved November 30, 2016) describes a large national survey. In a representative sample of Americans ages 14 to 18 years, 45% indicated that they usua
> The article “Streaming overtakes Live tV among consumer Viewing preferences” (Variety, april 22, 2015) states that “U.S. consumers are more inclined to stream entertainment from an internet service than tune in to live TV.” This statement is based on a s
> The paper “teens and Distracted Driving” (pew internet & american Life project, 2009) reported that in a representative sample of 283 American teens age 16 to 17, there were 74 who indicated that they had sent a text message while driving. For purposes o
> The paper “Debt Literacy, financial experiences and over-indebtedness” (Social Science Research Network, working paper w14808, 2008) included data from a survey of 1000 Americans. One question on the survey was: “You owe $3000 on your credit card. You pa
> Let p denote the proportion of students at a large university who plan to purchase a campus meal plan in the next academic year. For a large-sample z test of H0: p = 0.20 versus Ha: p(0.20, find the P-value associated with each of the following values of
> Assuming a random sample from a large population, for which of the following null hypotheses and sample sizes is the large-sample z test appropriate? a. H0: p = 0.2, n = 25 b. H0: p = 0.6, n = 200 c. H0: p = 0.9, n = 100 d. H0: p = 0.05, n = 75
> USA TODAY (february 17, 2011) reported that 10% of 1008 American adults surveyed about their use of e-mail said that they had ended a relationship by e-mail. You would like to use this information to estimate the proportion of all adult Americans who hav
> The article “iphone can be addicting, Says new Survey” (www.msnbc.com, march 8, 2010) described a survey administered to 200 college students who owned an iPhone. One of the questions on the survey asked students if th
> Researchers carried out an experiment to evaluate the effectiveness of using acupuncture to treat heel pain. The experiment is described in the paper “effectiveness of trigger point Dry needling for plantar heel pain: a randomized controlled trial” (Phys
> Many fundraisers ask for donations using e-mail and text messages. The paper “now or never! the effect of Deadlines on charitable giving: evidence from two natural field experiments” (Journal of Behavioral and Experimental Economics [2016]: 1–10) describ
> In a test of hypotheses about a difference in treatment proportions, what does it mean when the null hypothesis is not rejected?
> The report “Audience Insights: Communicating to Teens (Aged 12–17)” (2009, www.cdc.gov) described teens’ attitudes about traditional media, such as TV, movies, and newspapers. In a representative sample of American teenage girls, 41% said newspapers were
> The report titled “Digital Democracy Survey” (2016, www .deloitte.com/us/tmttrends, retrieved December 16, 2016) stated that 31% of the people in a representative sample of adult Americans age 33 to 49 rated a landline telephone among the three most impo
> The news release referenced in the previous exercise also included data from independent samples of teenage drivers and parents of teenage drivers. In response to a question asking if they approved of laws banning the use of cell phones and texting while
> The Insurance Institute for Highway Safety issued a news release titled “Teen Drivers Often Ignoring Bans on Using Cell Phones” (June 9, 2008). The following quote is from the news release: Just 1–2 months prior to the ban’s Dec. 1, 2006, start, 11% of t
> The article “americans Say no to electric cars Despite gas prices” (USA TODAY, may 25, 2011) describes a survey of public opinion on issues related to rising gas prices. The survey was conducted by Gallup, a national p
> As part of a study described in the report “i can’t get my work Done!” (harmon.ie/blog/i-cant-get-my-work -done-how-collaboration-social-tools-drain-productivity, 2011, retrieved may 6, 2017), people
> A report in USA TODAY described an experiment to explore the accuracy of wearable devices designed to measure heart rate (“wearable health monitors not always reliable, study shows,” USA TODAY, october 12, 2016). The researchers found that when 50 volunt
> Example 11.1 describes a study in which 354 of 708 people in the sample of 18- to 29-year-olds and 412 of the 1029 people in the sample of 30- to 49-year-olds said that they thought it was OK to use a cell phone in a restaurant. Note that the sample size
> An article titled “tcU horned frogs game preview (part 1)” (www.uwdawgpound.com/2016/11/26/13710900 /washington-huskies-tcu-horned-frogs-game-preview-part-1, retrieved December 20, 2016) previews a college basketball g
> Researchers were interested in comparing regular- intensity exercise and high-intensity exercise for patients recovering from hospitalization due to chronic obstructive pulmonary disease (COPD). The researchers followed patients in Denmark who were enrol
> Example 11.3 describes the results of a survey of 1129 full-time college faculty and 293 part-time college faculty. Survey participants were asked if they require undergraduate students to submit papers through plagiarism-detection software; 40% of the f
> The article “rapid evolutionary response to a transmissible cancer in tasmanian Devils” (www.nature.com /articles/ncomms12684, retrieved December 20, 2016) describes the spread of devil facial tumor disease (DFTD), whi
> The article “Spray flu Vaccine may work better than injections for tots” (San Luis Obispo Tribune, May 2, 2006) described a study that compared flu vaccine administered by injection and flu vaccine administered as a nasal spray. Each of the 8000 children
> Women diagnosed with breast cancer whose tumors have not spread may be faced with a decision between two surgical treatments—mastectomy (removal of the breast) or lumpectomy (only the tumor is removed). In a long-term study of the effectiveness of these
> The article “fish oil Staves off Schizophrenia” (USA TODAY, february 2, 2010) describes a study in which 81 patients age 13 to 25 who were considered at risk for mental illness were randomly assigned to one of two groups. Those in one group took four fis
> In a study of a proposed approach for diabetes prevention, 339 people under the age of 20 who were thought to be at high risk of developing type I diabetes were assigned at random to one of two groups. One group received twice daily injections of a low d
> Some fundraisers believe that people are more likely to make a donation if there is a relatively quick deadline given for making the donation. The paper “now or never! the effect of Deadlines on charitable giving: evidence from two natural field experime
> Use the data given in the previous exercise to construct and interpret a 95% confidence interval estimate of the difference in the injury proportion for the traditional cleat treatment and the swivel disc shoe treatment.
> The article “footwear, traction, and the risk of athletic injury” (january 2016, www.lermagazine.com/article/footwear -traction-and-the-risk-of-athletic-injury, retrieved December 15, 2016) describes a study in which high school football players were giv
> Choice blindness is the term that psychologists use to describe a situation in which a person expresses a preference and then doesn’t notice when they receive something different than what they asked for. The authors of the paper “can chocolate cure blin
> The paper “passenger and cell phone conversations in Simulated Driving” (Journal of Experimental Psychology: Applied [2008]: 392–400) describes an experiment that investigated if talking on a cell phone while driving is more distracting than talking with
> Use the data given in the previous exercise to construct and interpret a 95% confidence interval estimate of the difference in the proportion experiencing pain relief for the surgery treatment and this proportion for the therapy treatment.
> In the experiment described in the article “Study points to benefits of Knee replacement Surgery over therapy alone” (The New York Times, October 21, 2015), adults who were considered candidates for knee replacement were followed for one year. Suppose th
> A headline that appeared in Woman’s World stated “black currant oil curbs hair Loss!” (Woman’s World, april 4, 2016). This claim was based on an experiment described in the paper “effect of a nutritional Supplement on hair Loss in women” (Journal of Cosm
> Gallup surveyed adult Americans about their consumer debt (“americans’ big Debt burden growing, not evenly Distributed,” february 4, 2016, www.gallup.com, retrieved December 15, 2016). They reported that 47% of millennials (those born between 1980 and 19
> The report referenced in the previous exercise also stated that the proportion who thought their parents would help with buying a house or renting an apartment for the sample of young adults was 0.37. For the sample of parents, the proportion who said th
> The report “Young people Living on the edge” (greenberg Quinlan rosner research, 2008) summarizes a survey of people in two independent random samples. One sample consisted of 600 young adults (age 19 to 35), and the other sample consisted of 300 parents
> The article referenced in the previous exercise also reported that 53% of the Republicans surveyed indicated that they were opposed to making women register for the draft. Would you use the large-sample test for a difference in population proportions to
> The article “most women oppose having to register for the Draft” (february 10, 2016, www.rasmussenreports. com, retrieved December 15, 2016) describes a survey of likely voters in the United States. The article states that 36% of those in a representativ
> The Interactive Advertising Bureau surveyed a representative sample of 1000 adult Americans and a representative sample of 1000 adults in China (“majority of Digital Users in U.S. and china regularly Shop and purchase via e-commerce,&ac
> The paper “on the nature of creepiness” (New Ideas in Psychology [2016]: 10–15) describes a study to investigate what people think is “creepy.” Each person in a sample of women and a sample of men were asked to do the following: Imagine a close friend o
> A hotel chain is interested in evaluating reservation processes. Guests can reserve a room by using either a telephone system or an online system that is accessed through the hotel’s web site. Independent random samples of 80 guests who reserved a room b
> In a survey of mobile phone owners, 53% of iPhone users and 42% of Android phone users indicated that they upgraded their phones at least every two years (“americans Split on how often they Upgrade their Smartphones,”
> Many people believe that they experience “information overload” in today’s digital world. The report “information overload” (pew research center, December 7, 2016) describes a survey in which people were asked if they feel overloaded by information. In a
> The Bureau of Labor Statistics report referenced in the previous exercise also reported that 7.3% of high school graduates were unemployed in October 2013 and 5.7% of high school graduates were unemployed in October 2014. Suppose that the reported percen
> The bureau of Labor Statistics (www.bls.gov/opub /ted/2014/ted_20141112.htm, retrieved December 13, 2016) reported that 3.8% of college graduates were unemployed in October 2013 and 3.1% of college graduates were unemployed in October 2014. Suppose that
> The article “more teen Drivers See marijuana as oK; it’s a Dangerous trend” (USA TODAY, February 23, 2012) describes two surveys of U.S. high school students. One survey was conducted in 2009 and the other was conducted in 2011. In 2009, 78% of the peopl
> A survey of high school students is described in the report “Students on Stem” (changetheequation.org/students -stem, retrieved December 12, 2016). The report states that 14% of those in a sample of students in low-income households (defined as a househo
> The report “the new food fights: U.S. public Divides over food Science” (December 1, 2016, www.pewinternet.org, retrieved December 10, 2016) states that younger adults are more likely to see foods with genetically modified ingredients as being bad for th
> The following graphical display is similar to one that appeared in USA TODAY (february 16, 2012). The display summarizes data from surveys of male and female American adults. Assume that the two samples were independently selected representative samples
> A Harris Poll press release dated November 1, 2016 summarized results of a survey of 2463 adults and 510 teens age 13 to 17 (“american teens no Longer more Likely than adults to believe in god, miracles, heaven, jesus, angels, or the Devil,” www.theharri
> The U.S. Department of Transportation reported that in a large study of mobile phone use while driving conducted in 2015, 4.4% of female drivers observed and 3.5% of male drivers observed were using a handheld mobile phone while driving (“traffic Safety
> According to the U.S. census bureau (www.census.gov), the percentage of U.S. residents living in poverty in 2015 was 12.2% for men and 14.8% for women. These percentages were estimates based on data from large representative samples of men and women. Sup
> An article titled “The Latest on Workplace Monitoring and Surveillance” (American Management Association, November 17, 2014) referred to the “2007 Electronic Monitoring & Surveillance Survey.” In a summary of survey results submitted by 304 U.S. business
> The article “Report: More Than Half of DC-Area Millennials Are Using Ride-Hailing Apps” (June 23, 2016, www .washingtonian.com/2016/06/23/report-half-dc-area -millennials-using-ride-hailing-apps/, retrieved May 4, 2017
> A survey on SodaHead (www.sodahead.com/survey /featured/anonymous-advice/?results51, retrieved May 13, 2016) reported that 603 out of 753 respondents replied “no” to the question “Should you be friend
> USA TODAY (January 24, 2012) reported that ownership of tablet computers and e-readers is soaring. Suppose you want to estimate the proportion of students at your college who own at least one tablet or e-reader. What sample size would you use in order to
> Data from a representative sample were used to estimate that 32% of all computer users in 2011 had tried to get on a Wi-Fi network that was not their own in order to save money (USA TODAY, May 16, 2011). You decide to conduct a survey to estimate this pr
> In spite of the potential safety hazards, some people would like to have an Internet connection in their car. A preliminary survey of adult Americans has estimated the proportion of adult Americans who would like Internet access in their car to be somewh
> The 1991 publication of the book Final Exit, which includes chapters on doctor-assisted suicide, caused a great deal of controversy in the medical community. The Society for the Right to Die and the American Medical Association quoted very different figu
> The article “Should Canada Allow Direct-to-Consumer Advertising of Prescription Drugs?” (Canadian Family Physician [2009]: 130–131) calls for the legalization of advertising of prescription drugs in Canada. Suppose you wanted to conduct a survey to estim
> A manufacturer of small appliances purchases plastic handles for coffeepots from an outside vendor. If a handle is cracked, it is considered defective and can’t be used. A large shipment of plastic handles is received. How many handles from the shipment
> In 2010, the online security firm Symantec estimated that 63% of computer users don’t change their passwords very often (www.cnet.com/news/survey-63-dont -change-passwords-very-often, retrieved November 19, 2016). Because this estimate may be outdated, s
> A discussion of digital ethics appears in the article “Academic Cheating, Aided by Cell Phones or Web, Shown to be Common” (Los Angeles Times, June 17, 2009). One question posed in the article is: What proportion of college students have used cell phones
> The report referenced in the previous exercise also indicated that 33% of those in a representative sample of 533 homeowners in southern states said that they had considered installing solar panels. a. Use the given information to construct and interpre
> The report “The Politics of Climate” (Pew Research Center, October 4, 2016, www.pewinternet.org/2016/10/04 /the-politics-of-climate, retrieved May 6, 2017) summarized data from a survey on public opinion of renewable and other energy sources. It was repo
> The report “The 2016 Consumer Financial Literacy Survey” (The National Foundation for Credit Counseling, www.nfcc.org, retrieved October 28, 2016) summarized data from a representative sample of 1668 adult Americans. Based on data from this sample, it wa
> The article referenced in the previous exercise also indicated that 811 of the 1001 students surveyed said that they would feel restricted if they could only work on digital devices. Would a 95% confidence interval for the proportion of students age 13 t
> The article “Write It by Hand to Make It Stick” (Advertising Age, July 27, 2016) summarizes data from a survey of 1001 students age 13 to 19 years. Of the students surveyed, 851 reported that they learn best using a mix of digital and nondigital tools. C
> One thousand randomly selected adult Americans participated in a survey conducted by the Associated Press (June 2006). When asked “Do you think it is sometimes justified to lie, or do you think lying is never justified?” 52% responded that lying was neve
> In 2010, the National Football League adopted new rules designed to limit head injuries. In a survey conducted in 2015 by the Harris Poll, 1216 of 2096 adults indicated that they were football fans and followed professional football. Of these football fa
> The article “Most Dog Owners Take More Pictures of Their Pet Than Their Spouse” (August 22, 2016, news.fastcompany.com/most-dog-owners-take-more-pictures-oftheir-pet-than-their-spouse-4017458, retrieved May 6, 2017) indicates that in a sample of 1000 dog
> The report “Job Seeker Nation Study 2016” (www .jobvite.com/wp-content/uploads/2016/03/Jobvite _Jobseeker_Nation_2016.pdf, retrieved May 6, 2017) summarized a survey of 2305 working adults. The report indicates that 484 of the working adults surveyed sai
