![Introductory Statistics, Books a la Carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (10th Edition)](https://www.bartleby.com/isbn_cover_images/9780134270364/9780134270364_largeCoverImage.gif)
Concept explainers
Medical Marijuana. An issue with legalization of medical marijuana is “diversion” the process in which medical marijuana prescribed for one person is given, traded, or sold to someone who is not registered for medical marijuana use. Researchers S. Sautel el al. study the issue of diversion in the article “Medical Marijuana Use Among Adolescents in Substance Abuse Treatment” (Journal of the American Academy of Child and Adolescent Psychiatry, Vol. 51, No. 7, pp. 694–702), The mean number of days that 120 adolescents in substance abuse treatment used medical marijuana in the last 6 months was 102.72. Assume the population standard deviation is 32 days.
- a. Find a 95% confidence interval for the mean number of days, μ, of diverted medical marijuana use in the last 6 months of all adolescents in substance abuse treatment.
- b. Repeat part (a) at a 90% confidence level.
- c. Draw a graph similar to Fig. 8.6 on page 343 to display both confidence intervals.
- d. Which confidence interval yields a more accurate estimate of μ? Explain your answer.
![Check Mark](/static/check-mark.png)
Want to see the full answer?
Check out a sample textbook solution![Blurred answer](/static/blurred-answer.jpg)
Chapter 8 Solutions
Introductory Statistics, Books a la Carte Plus NEW MyLab Statistics with Pearson eText -- Access Card Package (10th Edition)
- 2. Researchers G. Evans and E. Kantrowitz explored the health consequences forexposure to many different environmental risks in the journal article “SocioeconomicStatus and Health: The Potential Role of Environmental Risk Exposure” (AnnualReview of Public Health, Vol. 23, No. 1, pp. 303-331). According to research, 65% ofpreschool children living in poverty have been exposed to cigarette smoke at home. If200 preschool children living in poverty are selected at random, identify the probabilitythat at least 125 have been exposed to cigarette smoke at home?3. Ten students sat for a Mathematics examination which comprises two papers. Theirscores out of 100 are given in the table below:Student 1 2 3 4 5 6 7 8 9 10Paper 1 31 43 50 52 62 40 44 60 55 27Paper 2 35 58 43 68 92 59 25 55 50 18(a) Identify a 95% confidence interval for the mean of the differences between thescores for Paper 1 and Paper 2.(b) At the 5% significance level, test whether the mean scores of Paper 1 andPaper 2 are…arrow_forward19. Road Patrol. In the paper “Injuries and Risk Factors in a 100-Mile (161-km) Infantry Road March" (Preventative Medicine, Vol. 28, pp. 167–173), K. Reynolds et al. reported on a study com- missioned by the U.S. Army. The purpose of the study was to im- prove medical planning and identify risk factors during multiple-day road patrols by examining the acute effects of long-distance marches by light-infantry soldiers. Each soldier carried a standard U.S. Army rucksack, Meal-Ready-to-Eat packages, and other field equipment. A sample of 10 participating soldiers revealed the following data on total load mass, in kilograms. 48 50 45 49 44 47 37 54 40 43 a. Obtain the sample mean of these 10 load masses. b. Obtain the range of the load masses. c. Obtain the sample standard deviation of the load masses.arrow_forwardHepatitis B and Pancreatic Cancer. 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…arrow_forward
- Behavioural Researchers view the internet and social media addiction as a disorder characterized by the excessive use of Facebook, Instagram, Snap chat, Twitter and other forms of social media such that it affects other aspects of life, including real-life relationships and academic achievement among those still in education. The paper "The Association between Aggressive Behaviors and Internet Addiction and Online Activities in Adolescents" (Journal of Adolescent Health [2009]: 598–605) reported on a study of more than 9400 adolescents. Each participant in the study was assessed using the Chen Internet Addiction Scale to determine if he or she suffered from Internet addiction. The following statements are based on the survey results: a) 51.8% of the study participants were female and 48.2% were male. b) 13.1% of females suffered from Internet addiction. c) 24.8% of the males suffered from Internet addiction Required i) What is the probability that an adolescent is addicted to the…arrow_forwardIn August and September 2005, Hurricanes Katrina and Rita caused extraordinary flooding in New Orleans, Louisiana. Many homes were severely damaged or destroyed; of those that survived, many required extensive cleaning. It was thought that cleaning flood-damaged homes might present a health hazard due to the large amounts of mold present in many of the homes. The article “Health Effects of Exposure to Water-Damaged New Orleans Homes Six Months After Hurricanes Katrina and Rita” (K. Cummings, J. Cox-Ganser, et al., American Journal of Public Health, 2008:869–875) reports that in a sample of 365 residents of Orleans Parish who had participated in the cleaning of one or more homes, 77 had experienced symptoms of wheezing, and in a sample of 179 residents who had not participated in cleaning, 23 reported wheezing symptoms (numbers read from a graph). Can you conclude that the frequency of wheezing symptoms is greater among those residents who participated in the cleaning of flood-damaged…arrow_forwardhe paper "From Dr. Kildare to Grey's Anatomy"† describes several studies of how the way in which doctors are portrayed on television might influence public perception of doctors. One study was described as follows. Rebecca Chory, Ph.D., now an associate professor of communication at West Virginia University, began studying the effect of such portrayals on patients' attitudes toward physicians. Using a survey of 300 undergraduate students, she compared perceptions of physicians in 1992—the end of the era when physicians were shown as all-knowing, wise father figures—with those in 1999, when shows such as ER and Chicago Hope (1994–2000) were continuing the transformation to showing the private side and lives of physicians, including vivid demonstrations of their weaknesses and insecurities. Dr. Chory found that, regardless of the respondents' personal experience with physicians, those who watched certain kinds of television had declining perceptions of physicians' composure and regard…arrow_forward
- Friendship Motivation. In the article “Assessing Friendship Motivation During Preadolescence and Early Adolescence” (Journal of Early Adolescence, Vol. 25, No. 3, pp. 367–385), J. Richard and B. Schneider described the properties of the Friendship Motivation Scale for Children (FMSC), a scale designed to assess children’s desire for friendships. Two interesting conclusions are that friends generally report similar levels of the FMSC and girls tend to score higher on the FMSC than boys. Boys in the seventh grade scored a mean of 9.32 with a standard deviation of 1.71, and girls in the seventh grade scored a mean of 10.04 with a standard deviation of 1.83. Assuming that FMSC scores are normally distributed, determine the percentage of seventh-grade boys who have FMSC scores within a. one standard deviation to either side of the mean. b. two standard deviations to either side of the mean. c. three standard deviations to either side of the mean. d. Repeat parts (a)–(c) for seventh-grade…arrow_forwardA study is being conducted on the effect of gas price on the number of miles driven in a given month. Residents in two cities, one on the East Coast and one on the West Coast, are randomly selected and asked to complete a questionnaire on the type of car they drive, the number of miles they live from work, the number of children under 18 in their household, their monthly income, and the number of miles they have driven over the past 30 days. (a) List the response variable(s) and the type of measurement scale (nominal/ordinal/interval/ratio) associated with each response variable. (b) Also, state whether this study is an experimental or observational study? Explain in brief the reason for your answer.arrow_forwardA study is being conducted on the effect of gas price on the number of miles driven in a given month. Residents in two cities, one on the East Coast and one on the West Coast, are randomly selected and asked to complete a questionnaire on the type of car they drive, the number of miles they live from work, the number of children under 18 in their household, their monthly income, and the number of miles they have driven over the past 30 days. (a) List the response variable(s) and the type of measurement scale (nominal/ordinal/interval/ratio) associated with each response variable.arrow_forward
- A study is being conducted on the effect of gas price on the number of miles driven in a given month. Residents in two cities, one on the East Coast and one on the West Coast, are randomly selected and asked to complete a questionnaire on the type of car they drive, the number of miles they live from work, the number of children under 18 in their household, their monthly income, and the number of miles they have driven over the past 30 days. (a) List the response variable(s) and the type of measurement scale (nominal/ordinal/interval/ratio) associated with each response variable. (b) Also, state whether this study is an experimental or observational study?arrow_forwardThe paper "From Dr. Kildare to Grey's Anatomy"† describes several studies of how the way in which doctors are portrayed on television might influence public perception of doctors. One study was described as follows. Rebecca Chory, Ph.D., now an associate professor of communication at West Virginia University, began studying the effect of such portrayals on patients' attitudes toward physicians. Using a survey of 300 undergraduate students, she compared perceptions of physicians in 1992—the end of the era when physicians were shown as all-knowing, wise father figures—with those in 1999, when shows such as ER and Chicago Hope (1994–2000) were continuing the transformation to showing the private side and lives of physicians, including vivid demonstrations of their weaknesses and insecurities. Dr. Chory found that, regardless of the respondents' personal experience with physicians, those who watched certain kinds of television had declining perceptions of physicians' composure and regard…arrow_forwardUndergraduate Binge Drinking. Alcohol consumption on college and university campuses has gained attention because undergraduate students drink significantly more than young adults who are not students. Researchers I. Balodis et al. studied binge drinking in undergraduates in the article “Binge Drinking in Undergraduates: Relationships with Gender, Drinking Behaviors, Impulsivity, and the Perceived Effects of Alcohol” (Behavioural Pharmacology, Vol. 20, No. 5, pp. 518–526). The researchers found that students who are binge drinkers drink many times a month with the span of each outing having a mean of 4.9 hours and a standard deviation of 1.1 hours. a. For samples of size 40, find the mean and standard deviation of all possible sample mean spans of binge drinking episodes. Interpret your results in words. b. Repeat part (a) with n = 120.arrow_forward
- Calculus For The Life SciencesCalculusISBN:9780321964038Author:GREENWELL, Raymond N., RITCHEY, Nathan P., Lial, Margaret L.Publisher:Pearson Addison Wesley,
![Text book image](https://www.bartleby.com/isbn_cover_images/9780321964038/9780321964038_smallCoverImage.gif)