Researchers sent out a survey to U.S. war veterans that asked a series of questions, including whether individuals surveyed weresmokers or nonsmokers (Seltzer et al. 1974). They found that nonsmokers were 27% more likely than smokers to respond to thesurvey within 30 days (based on the much larger number of smokers and nonsmokers who eventually responded).Hypothetically, if the study had ended after 30 days, what effect would this have on the estimate of the proportion of veteranswho smoke?Select the correct description of the effect.The estimate would be biased because of the underestimation of the true proportion of smokers.O The estimate would be biased because of the overestimation of the true proportion of smokers.O The estimate would not be biased because capping at 30 days would not change the estimated proportion of smokers.O The estimate would not be biased because the sample of veterans is a volunteer sample.

Given that nonsmokers were 27% more likely to respond to the survey within 30 days. If the study…

Answered: Researchers sent out a survey to U.S.…

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

Use the following data to answer question 13 - 16. Breast cancer is one of the leading causes of death in women prior to age fifty. A study of the effectiveness of regular breast self-examination (BSE) reported in the American Journal of Public Health found that 23 of 53 women who discovered a tumor through BSE had a tumor in an early stage. Of 178 women who discovered a tumor by accident, 48 had a tumor in an early stage. Let P1 and P2 denote the proportion of women who detected early stage tumor through BSE and by accident, and let P1 and P2 denote the corresponding estimates.
Serum estradiol is an important risk factor for breast cancer in postmenopausal women. To better understand the etiology of breast cancer, serum-estradiol samples were collected from 25 premenopausal women (at about the same time period of the menstrual cycle) of whom 10 were Caucasian and 15 were African American. The data are shown in Table 7.3. The distribution of serum estradiol is usually highly skewed (especially for premenopausal women), and we are reluctant to assume normality. Table 7.3 Serum estradiol and ethnicity in 25 premenopausal women, where 0=Caucasian and 1=African-American ID Serum_estradiol Ethic 1 94 0 2 54 1 3 31 0 4 21 1 5 46 1 6 56 0 7 18 1 8 19 1 9 12 1 10 14 0 11 25 0 12 35 1 13 22 1 14 71 0 15 43 1 16 35 1 17 42 1 18 50 1 19 44 1 20 41 0 21 28 0 22 65 0 23 31 0 24…
The medical community unanimously agrees on the health benefits of regular exercise, but are adults listening? During each of the past 15 years, a polling organization has surveyed americans about their exercise habits. In the most recent of these polls, slightly over half of all American adults reported that they exercise for 30 or more minutes at least three times per week. The following data show the percentages of adults who reported that they exercise for 30 or more minutes at least three times per week during each of the 15 years of this study. Year Percentage of Adults Who Exercise 30 or more minutes at least three times per week 1 41.1 2 45 3 47.2 4 45.6 5 46.5 6 44.4 7 47.7 8 49.9 9 48 10 49 11 50 12 52.2 13 50.7 14 54.5 15 52.3 use simple linear regression to find the parameters for the line that minimizes MSE for this time series. Do not round your interim computations and…
Consider the following studies. Study I: A researcher randomly divided 200 high school students into two groups. The first group was told to not exercise. The second group was told to exercise at least 5 hours each week. At the end of two months, the heart rates of each participant in each group were measured at rest. It was found that the group that exercised 5 hours a week had a significantly lower average heart rate. Study II: A researcher gathered 200 high school students randomly, asked them how long they exercised each week, and then measured their heart rates at rest. It was found that students who exercised at least 5 hours a week had a significantly lower average heart rate. Part A: Which study was experimental? Why? Study IStudy II Part B: List the explanatory and response variables in the studies. Explanatory: heart rate; Response: exercise timeExplanatory: student; Response: amount of exerciseExplanatory: exercise time; Response: heart rate Part C: State whether the…
A hypothetical study looks at the effect of drinking alcohol on health. Across all genders and age groups, people who do not drink tend to be healthier on average than people who do drink. However, people who drink regularly are on average healthier than those people who have recently stopped drinking. Is it reasonable to conclude that for the sake of health, we should not start drinking, but if we have already started drinking alcohol, it is healthier to continue and not to stop?
A recent study investigated whether cell phone users experience separation anxiety when they cannot access their phones. Because blood pressure increases with anxiety, the researchers used systolic blood pressure as an operational measure of anxiety. The experiment involved a random sample of cell phone users that were divided into two groups at random. One group of participants completed a survey while their phones were locked in a cabinet in a separate room and the other group of participants completed the same survey while their phones were nearby. (The survey questions were unrelated to cell phone use.) At the end of the survey, theresearchers measured each participant's systolic blood pressure. The same experiment was conducted in Montreal, Toronto, Vancouver, and St. Zotique. The blood pressure data for all participants needed are below. Use these data to answer the following question: comoute the estimated standard error of d for the data collected in toronto. Please answer to 5…
The phrase “Correlation does not equal causation” means: Question 30 options: there is no guarantee that a cause-and-effect relationship exists between two variables that are correlated. there is only a 30% chance that a cause-and-effect relationship exists between two variables. a cause-and-effect relationship only certainly exists when data are gathered in a specific way. a cause-and-effect relationship can only exist with ratio-level variables.
Serum estradiol is an important risk factor for breast cancer in postmenopausal women. To better understand the etiology of breast cancer, serum-estradiol samples were collected from 25 premenopausal women (at about the same time period of the menstrual cycle) of whom 10 were Caucasian and 15 were African American. The data are shown in Table 7.3. The distribution of serum estradiol is usually highly skewed (especially for premenopausal women), and we are reluctant to assume normality. Table 7.3 Serum estradiol and ethnicity in 25 premenopausal women, where 0=Caucasian and 1=African-American. ID Serum_estradiol Ethic 1 94 0 2 54 1 3 31 0 4 21 1 5 46 1 6 56 0 7 18 1 8 19 1 9 12 1 10 14 0 11 25 0 12 35 1 13 22 1 14 71 0 15 43 1 16 35 1 17 42 1 18 50 1 19 44 1 20 41 0 21 28 0 22 65 0 23 31 0 24…
Please help me answer this with complete solution.
In an article published in 2012 at Telegraph.co.uk, Warranty Direct gave engine failure rates for a variety of car brands based on their database of UK direct consumer warranties. The following are known: ● Hondas failed at a rate of 1 in 344. ● Fords failed at a rate of 1 in 80. ● Audis failed at a rate of 1 in 27. Suppose Hondas account for 20% of sales at a particular dealer, Audis 30%, and Fords 50%. Assuming the engine failure rates apply to these vehicles. Determine the probability that a randomly selected vehicle from this dealer will experience engine failure.
A psychologist has developed a mental alertness test. She wishes to study the effects (if any) of type of food consumed on mental alertness. Twenty-one volunteers were randomly divided into two groups. Both groups were told to eat the amount they usually eat for lunch at noon. At 2:00 P.M., all subjects were given the alertness test. Group A had a low-fat lunch with no red meat, lots of vegetables, carbohydrates, and fiber. Group B had a high-fat lunch with red meat, vegetable oils, and low fiber. The only drink for both groups was water. The test scores are shown below. Group A 75 82 96 54 78 59 67 53 97 85 66 Group B 70 80 79 60 62 71 52 69 64 88 51 74 Use a 10% level of significance to test the claim that there is no difference in mental alertness distributions based on type of lunch. (a) What is the level of significance?State the null and alternate hypotheses. Ho: Distributions are different. H1: Distributions are the same.Ho: Distributions are the same. H1:…

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS