Concept explainers
Leisure Activities and Dementia. An article appearing in the Los Angeles Times discussed the study “Leisure Activities and the Risk of Dementia in the Elderly” (New England Journal of Medicine, Vol. 348, pp. 2508–2516) by J. Verghese et al. The article in the Times, titled “Crosswords Reduce Risk of Dementia,” contained the following statement: “Elderly people who frequently read, do crossword puzzles, practice a musical instrument or play board games cut their risk of Alzheimer’s and other forms of dementia by nearly two-thirds compared with people who seldom do such activities.” Comment on the statement in quotes, keeping in mind the type of study for which causation can be reasonably inferred.
Want to see the full answer?
Check out a sample textbook solutionChapter 1 Solutions
INTRO.STATISTICS,TECH.UPDT.-W/MYSTATLAB
Additional Math Textbook Solutions
Elementary Statistics: Picturing the World (7th Edition)
A First Course in Probability (10th Edition)
Precalculus: A Unit Circle Approach (3rd Edition)
APPLIED STAT.IN BUS.+ECONOMICS
College Algebra (7th Edition)
Elementary Statistics ( 3rd International Edition ) Isbn:9781260092561
- Urban Travel Times Population of cities and driving times are related, as shown in the accompanying table, which shows the 1960 population N, in thousands, for several cities, together with the average time T, in minutes, sent by residents driving to work. City Population N Driving time T Los Angeles 6489 16.8 Pittsburgh 1804 12.6 Washington 1808 14.3 Hutchinson 38 6.1 Nashville 347 10.8 Tallahassee 48 7.3 An analysis of these data, along with data from 17 other cities in the United States and Canada, led to a power model of average driving time as a function of population. a Construct a power model of driving time in minutes as a function of population measured in thousands b Is average driving time in Pittsburgh more or less than would be expected from its population? c If you wish to move to a smaller city to reduce your average driving time to work by 25, how much smaller should the city be?arrow_forward5) A researcher wants to explore the differences in health effects from two different types of sugar. She hypothesizes that artificial sweetener has lower long term health benefits than natural sugar. She will try one more approach... This time she will gather two groups of people, and she will match each person in one group to another person in the other group by some similar characteristics. For example, if there is a female age 30 in one group, she will compare that female directly to another female age 30 in the other group. If there is a male age 60 in one group, she will compare that male directly to another male age 60 in the other group. What type of t-test should she use for this method? Group of answer choices a) One sample b) No answer text provided. c) Paired Samples d) Independent Samplesarrow_forward(3.8.8) The Massachusetts Department of Public Health collects annual data on brain injuries in school athletics. In 2011, the department reported that in their survey of middle and high school students, about 18 percent of students who played on a team in the previous 12 months reported symptoms of a traumatic brain injury while playing sports. These symptoms include losing consciousness, having memory problems, double or blurry vision, headaches, or nausea. During that year, about 200,000 Massachusetts high school students participated in extracurricular sports. How many reported injuries were there? 200,000 x 0.18= 36,000 people reported injuries. b. The survey reports the number injured as a percentage of the number of students participating in extracurricular sports. What is the number injured as a percentage of the population of Massachusetts? In 2011, the population of Massachusetts was 6,512,227arrow_forward
- Researchers are interested in conducting a study to determine if men or women suffer more from anxiety. Would you conduct an experimental study or an observational study to answer this question?arrow_forwardCoffee and Depression: Researchers conducted a study investigating the relationship between caffeinated coffee consumption and risk of depression in women. They collected data on 50,739 women free of depression symptoms at the start of the study in the year 1996, and these women were followed through 2006. The researchers used questionnaires to collect data on caffeinated coffee consumption, asked each individual about physician-diagnosed depression, and also asked about the use of antidepressants. The table below shows the distribution of incidences of depression by amount of caffeinated coffee consumption. (M. Lucas et al, 2011). Tip: Do NOT include the TOTAL row and column in your table when you copy into your technology application such as Statcrunch or a Calculator. ≤ 1 cup/week 2-6 cups/week 1 cup/day 2-3 cups/day ≥ 4 cups/day Total 373 905 564 95 2607 Clinical Depression: Yes 670 Clinical Depression: No 11545 6244 16329 11726 2288 48132 Total 12215 6617 17234 12290 2383 50739arrow_forwardIs it a good idea to give routine cancer screening test for a healthy person ?arrow_forward
- The report Controlling Road Rage: A Literature Review and Pilot Study was prepared for the AAA Foundation for Traffic Safety by D. Rathbone and J. Huckabee. The authors discussed the results of a literature review and pilot study on how to prevent aggressive driving and road rage. Road rage is defined as “… an incident in which an angry or impatient motorist or passenger intentionally injures or kills another motorist, passenger, or pedestrian, or attempts or threatens to injure or kill another motorist, passenger, or pedestrian.” One aspect of the study was to investigate road rage as a function of the day of the week. The following table provides a frequency distribution for the days on which 69 road-rage incidents occurred. Day Frequency Sunday 5 Monday 5 Tuesday 11 Wednesday 12 Thursday 11 Friday 18 Saturday 7 At the 5% significance level, do the data provide sufficient evidence to conclude that road-rage incidents are more likely to occur on…arrow_forwardThe report Controlling Road Rage: A Literature Review and Pilot Study was prepared for the AAA Foundation for Traffic Safety by D. Rathbone and J. Huckabee. The authors discussed the results of a literature review and pilot study on how to prevent aggressive driving and road rage. Road rage is defined as “... an incident in which an angry or impatient motorist or passenger intentionally injures or kills another motorist, passenger, or pedestrian, or attempts or threatens to injure or kill another motorist, passenger, or pedestrian.” One aspect of the study was to investigate road rage as a function of the day of the week. The following table provides a frequency distribution for the days on which 69 road-rage incidents occurred. Day Frequency Sunday 5 Monday 5 Tuesday 11 Wednesday 12 Thursday 11 Friday 18 Saturday 7 At the 5% significance level, do the data provide sufficient evidence to conclude that road-rage incidents are more likely to occur on some days…arrow_forwardThe University of Michigan Health and Retirement Study (HRS) surveys more than 22,000 Americans over the age of 50 every two years. A subsample of the HRS participated in an Internet-based survey that collected information on a number of topical areas, including health (physical and mental health behaviors), psychosocial items, economics (income, assets, expectations, and consumption), and retirement. Two of the questions asked were: "Would you say your health is excellent, very good, good, fair, or poor?" and “Do you smoke cigarettes now?" Here is the two-way table that summarizes the answers on these two questions: Current smoker Нealth Yes No Excellent 25 484 Very good 115 1557 Good 145 1309 Fair 90 545 Рoor 29 11 This table gives the responses of a survey of 4310 Americans to questions about their health and whether they currently smoke cigarettes. You might find this chi-square table useful. Do these data satisfy our guidelines for safe use of the chi-square test? Enter your…arrow_forward
- What is a confounding variable in research, and how can it affect the results of a study? Provide an example of a confounding variable in a hypothetical study.arrow_forward“The rapid growth of video game popularity has generated concern among practitioners, parents, scholars, and politicians,” wrote researchers Hope M. Cummings and Elizabeth A. Vandewater. In their study, Cummings and Vandewater measured the time adolescents spent playing video games as well as time spent doing other activities, such as interacting with family and friends, reading or doing homework, or playing sports. [Source: Cummings, H., & Vandewater, E. (2007). Relation of adolescent video game play to time spent in other activities. Archives of Pediatrics & Adolescent Medicine, 161(7), 684–689.] After reading about the study conducted by Cummings and Vandewater, you decide to conduct a similar study among a sample of 10 teenage girls. You ask the girls to keep a log of their activities for a day. You want to test whether the amount of time girls spend playing video games is correlated with the amount of time they read for pleasure. You realize that because some of the…arrow_forward“The rapid growth of video game popularity has generated concern among practitioners, parents, scholars, and politicians,” wrote researchers Hope M. Cummings and Elizabeth A. Vandewater. In their study, Cummings and Vandewater measured the time adolescents spent playing video games as well as time spent doing other activities, such as interacting with family and friends, reading or doing homework, or playing sports. [Source: Cummings, H., & Vandewater, E. (2007). Relation of adolescent video game play to time spent in other activities. Archives of Pediatrics & Adolescent Medicine, 161(7), 684–689.] After reading about the study conducted by Cummings and Vandewater, you decide to conduct a similar study among a sample of 10 teenage girls. You ask the girls to keep a log of their activities for a day. You want to test whether the amount of time girls spend playing video games is correlated with the amount of time they read for pleasure. You realize that because some of the…arrow_forward
- Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage LearningGlencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
- Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL