In a study of how depression may affect one's ability to survive a heart attack, the researchers reported the ages of the two groups they examined. The mean age of 2397 patients without cardiac disease was 69.8 years, while for the 450 patients with cardiac disease, the mean age was 74.0, respectively. Furthermore, 32% of the diseased group were smokers, compared with only 23.7% of those free of heart disease. (1) Determine a 96% confidence interval for the difference in the proportions of smokers in the two groups. (ii) Indicate whether the two groups in the study were different. State the assumptions in order to proceed with the confident interval construction. (ii)

In a study of how depression may affect one's ability to survive a heart attack, the researchers reported the ages of the two groups they examined. The mean age of 2397 patients without cardiac disease was 69.8 years, while for the 450 patients with cardiac disease, the mean age was 74.0, respectively. Furthermore, 32% of the diseased group were smokers, compared with only 23.7% of those free of heart disease. (1) Determine a 96% confidence interval for the difference in the proportions of smokers in the two groups. (ii) Indicate whether the two groups in the study were different. State the assumptions in order to proceed with the confident interval construction. (ii)

Name: In a study of how depression may affect one's ability to survive a he
Uploaded: 2024-03-20T07:07:12.000Z
Channel: Bartleby
Description: In a study of how depression may affect one's ability to survive a heart attack, theresearchers reported the ages of the two groups they examined. The mean age of2397 patients without cardiac disease was 69.8 years, while for the 450 patients withca

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The accompanying table summarizes data from a survey of 3,594 parents with school-aged children. In this survey, parents were asked if they were completely satisfied with the education their oldest child receives. School Type Percentage of ParentsCompletely Satisfied Public 28% Private 62% Of the 3,594 parents surveyed, 608 were parents whose oldest child attended a private school. The parents participating in this survey were thought to be representative of U.S. parents of school-aged children. (a) Use the given information to determine the number of parents surveyed falling into each of the cells in the table below. (Round your answers to the nearest integer.) CompletelySatisfied Not CompletelySatisfied Total Public School Private School 608 Total 3,594 (b) Estimate the probability that a randomly selected parent of school-aged children is completely satisfied with his or her oldest child's education. (Round your answer to four decimal…
Public relation companies conducted two surveys about deodorants. The first survey asked a random sample of 500 men about their use of a natural deodorant. A second survey asked the same questions to a random sample of 550 women. In these two studies, 68% of men and 44% of women stated they were dissatisfied with the effectiveness of natural deodorants. Use these results to answer the following questions about the proportion of men and women's satisfaction with natural deodorants. (Round to the nearest whole person as needed). Is there a statistically significant difference between men and women's satisfaction with natural deodorants? Yes, the proportion of men that are satisfied with natural deodorants is significantly less than the proportion of women that are satisfied with natural deodorants because both the lower limit and the upper limit of the confidence interval are positive values. Yes, the proportion of men that are satisfied with natural…
x Resorts & Spas, a magazine devoted to upscale vacations and accommodations, published its Reader's Choice List of the top 20 independent beachfront boutique hotels in the world. The data shown are the scores received by these hotels based on the results from Resorts & Spas' annual Readers' Choice Survey. Each score represents the percentage of respondents who rated a hotel as excellent or very good on one of three criteria (comfort, amenities, and in-house dining). An overall score was also reported and used to rank the hotels. The highest ranked hotel, the Muri Beach Odyssey, has an overall score of 94.3, the highest component of which is 97.7 for in-house dining. If required, round your answer to three decimal places. Click on the datafile logo to reference the data. Hotel Overall Comfort Amenities In-House Dining Muri Beach Odyssey 94.3 94.5 90.8 97.7 Pattaya Resort 92.9 96.6 84.1 96.6 Sojourner's Respite 92.8 99.9 100.0 88.4…
Pls help
The authors of a paper compared two different methods for measuring body fat percentage. One method uses ultrasound, and the other method uses X-ray technology. Body fat percentages using each of these methods for 16 athletes (a subset of the data given in a graph that appeared in the paper) are given in the accompanying table. You can assume that the 16 athletes who participated in this study are representative of the population of athletes. Athlete X-ray Ultrasound 1 5.00 4.25 2 12.00 8.75 3 9.25 9.00 4 12.00 11.75 5 17.25 17.00 6 29.50 27.50 7 5.50 6.50 8 6.00 6.75 9 8.00 8.75 10 9.50 10.50 11 9.25 9.50 12 11.00 12.00 13 12.00 12.25 14 14.00 15.50 15 17.00 18.00 16 18.00 18.25 Use these data to estimate the difference in mean body fat percentage measurement for the two methods. Use a confidence level of 95%. (Use ?d = ?X-ray − ?ultrasound. Round your answers to three decimal places.) , % Interpret the interval in…
In a random survey, 2020 seventh graders and 3232 eighth graders are asked their preference on playing tennis. Of the students surveyed, 1818 students prefer to play tennis, and there are 1212 seventh graders who do not prefer to play tennis. Which two-way frequency table could represent the data?
According to a census company, 7.1% of all babies born are of low birth weight. An obstetrician wanted to know whether mothers between the ages of 35 and 39 years give birth to a higher percentage of low-birth-weight babies. She randomly selected 280 births for which the mother was 35 to 39 years old and found 31 low-birth-weight babies. Complete parts (a) through (c) below. (a) If the proportion of low-birth-weight babies for mothers in this age group is 0.071, compute the expected number of low-birth-weight births to 35- to 39-year-old mothers. What is the expected number of births to mothers 35 to 39 years old that are not low birth weight? The expected number of low-birth-weight births to 35- to 39-year-old mothers is 19.88 The expected number of births to mothers 35 to 39 years old that are not low birth weight is 260.12 (Type integers or decimals.) (b) Answer the obstetrician's question at the a = 0.10 level of significance using the chi-square goodness-of-fit test. State the…
Ex. 1 A survey of 80 r/s California State University students indicates that 52 of them work. An independent survey of 40 University of California students indicates that 20 of them work. Construct a 95% c.i. for the difference between the overall percent of CSU students who work and the UC percent.
A marketing firm is doing research for an Internet-based company. It wants to appeal to the age group of people who spend the most money online. The company wants to know if there is a difference in the mean amount of money people spend per month on Internet purchases depending on their age bracket. The marketing firm looked at two age groups, 1818-2424 years and 2525-3030 years, and collected the data shown in the following table. Let Population 1 be the amount of money spent per month on Internet purchases by people in the 1818-2424 age bracket and Population 2 be the amount of money spent per month on Internet purchases by people in the 2525-3030 age bracket. Assume that the population variances are not the same. Internet Spending per Month 1818-2424 Years 2525-3030 Years Mean Amount Spent 50.40 65.33 Standard Deviation 15.85 20.76 Sample Size 17 27 Step 1 of 2 : Construct an 80%80% confidence interval for the true difference between the mean amounts of…
Researchers conducted two surveys about teens are their use of social media. The first survey asked a random sample of 800 U.S. teens about their use of Instagram. A second survey asked the same questions to a random sample of 2253 Canadian teens. In these two studies, 73% of U.S. teens and 88% of Canadian teens said that they use Instagram. Use these results to answer the following questions about the proportion of U.S. and Canadian teens that use Instagram. Is there a statistically significant difference between the use of social media by U.S. teens and Canadian teens? No, there is no difference between the proportion of U.S. teens that use Instagram and the proportion of Canadian teens that use Instagram because both the lower limit and the upper limit of the confidence interval are negative values. Yes, the proportion of U.S. teens that use Instagram is significantly less than the proportion of Canadian teens that use Instagram difference because both…
A psychologist wanted to know if students in her class were more likely to cheat if they were low achievers. She divided her 60 students into three groups (low, middle, and high) based on their mean exam score on the previous three tests. She then asked them to rate how likely they were to cheat on an exam if the opportunity presented itself with a very limited chance for consequences. The students rated their desire to cheat on a scale ranging from 1-100, with lower numbers indicating less desire to cheat. Before opening the data, what would you hypothesize about this research question? Open the data set. Before running any statistical analyses, glance through the data. Do you think that your hypothesis will be supported? Conduct descriptive analyses and report them here. Conduct a one-way ANOVA. Report your statistical findings (including any applicable tables in APA format) here. What would you conclude from this analysis? What would be your next steps, if this…
In a survey of working parents (both parents working), one of the questions asked was "Have you refused a job, promotion, or transfer because it would mean less time with your family?" Two hundred men and 200 women were asked this question. Twenty-nine percent of the men and 24% of the women responded "yes." a. Based on this survey, can we conclude that there is a difference in the proportion of man and women responding “yes" at the 0.05 level of significance? (i) State the null and alternative hypotheses (ii) What test statistics would you use and why? (iii) Compute the value of the test-statistic. (iv) What rejection region would you use? (v) State your conclusion in the context of the problem. b. What P-value is associated with this test? Based on this P-value, could H. be rejected at significance level 0.08? c. Find a 95% confidence interval for the difference between the proportion of men and women responding "yes." Based on this confidence interval, would your conclusion be the…