A sleep disorder specialist wants to test the effectiveness of a new drug that is reported to increase the number of hours of sleep patients get during the night. To do so,the specialist randomly selects nine patients and records the number of hours of sleep each gets with and without the new drug. The results of the two-night study arelisted below. Using this data, find the 90 % confidence interval for the true difference in hours of sleep between the patients using and not using the new drug.Assume that the hours of sleep are normally distributed for the population of patients both before and after taking the new drug.PatientHours of sleep without the drugHours of sleep with the new drug1 2 3 4 5 6 7 8 95.4 5.4 2.2 3.7 3.4 5.5 2.6 4.28.1 6.5 3.2 5.3 4.5 8 5.1 5.34.26.4Step 2 of 4: Calculate the sample standard deviation of the paired differences. Round your answer to six decimal places.Copy Data

The confidence interval for the true difference in hours of sleep between the patients using and not…

Answered: A sleep disorder specialist wants to…

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

A marketing study with a random sample of 400 results in 160 subjects reacting positively to the proposed product. Determine the 95% confidence interval for the population proportion.
In an engineering class, students want to determine the difference in the mean strength between two different types of building materials—Type A, which is relatively inexpensive, and Type B, which is slightly more expensive. The students take a random sample of 60 of the Type A building material and a random sample of 27 of the Type B building material. Given the mean strength for each sample, the students construct a 95% confidence interval for the difference in population means. (a) Determine the degrees of freedom for the conservative approach for finding the t critical value. (b) Find the t critical value associated with 95% confidence. (Use a table or SALT. Round your answer to two decimal places.)
A clinical trial is planned to compare an experimental medication designed to lower blood pressure to a placebo. Before starting the trial, a pilot study is conducted involving eight participants. The objective of the study is to assess how systolic blood pressure changes over time untreated. Systolic blood pressures are measured at baseline and again 4 weeks later Is there a statistically significant difference in blood pressures over time? Run the test at a 5% level of significance. Give each of the following to receive full credit: 1) the appropriate null and alternative hypotheses; 2) the appropriate test; 3) the decision rule; 4) the calculation of the test statistic; and 5) your conclusion including a comparison to alpha or the critical value. You MUST show all your work to receive full credit. Partial credit is available. Baseline 4 weeks 135 136 150 142 143 135 160 158 152 155 143 140 133 128 146 129
The dean of students at a large college is interested in learning about their opinions regarding the percentage of first-year students who should be given parking privileges in the main lot. He sends out an email survey to all students about this issue. A large number of first-year students reply but very few sophomores, juniors, and seniors reply. Based on the responses he receives, he constructs a 90% confidence interval for the true proportion of students who believe first-year students should be given parking privileges in the main lot to be (0.71, 0.79). Which of the following may have an impact on the confidence interval, but is not accounted for by the margin of error? response bias O nonresponse bias O sampling variation O undercoverage bias
2 different treatments were used to speed the relief time (in minutes) of migraines. 8 subjects received each treatment. The recovery times are listed below. Treatment 1: 20 19 29 25 34 32 39 38 Treatment 2: 18 18 16 17 29 28 21 37 Construct a 90% confidence interval for the difference in the relief time between the 2 treatments.
50 of the 600 medical students who were chosen at random stated they intended to work in a rural area. Calculate the 90% confidence interval for the actual percentage of medical students who intend to practice in rural areas. The responses shown here are estimates.
Several years ago, 45% of parents who had children in grades K-12 were satisfied with the quality of education the students receive. A recent poll asked 1,025 parents who have children in grades K-12 if they were satisfied with the quality of education the students receive. Of the 1,025 surveyed, 484 indicated that they were satisfied. Construct a 99% confidence interval to assess whether this represents evidence that parents' attitudes toward the quality of education have changed.
A learn-to-type software program claims that it can improve your typing skills. To test the claim and possibly help yourself out, you and six of your friends decide to try the program and see what happens. Use the table below to construct an 80% confidence interval for the true mean change in the typing speeds for people who have completed the typing program. Let Population 1 be the typing speed before taking the program and Population 2 be the typing speed after taking the program. Round the endpoints of the interval to one decimal place, if necessary. Typing Speeds (in Words per Minute) Before After 32 33 51 42 55 40 35 32 54 33 45 30 50 52
A major company would like to assess the impact of using a professional trainer to conduct a confidence-building workshop with its salespeople. A sample of 16 workers is obtained. Half (n = 8) attend the workshop and the other half (n = 8) serve as a control group. Two weeks later, each of the participants is given a questionnaire measuring the level of self-confidence. The data are as follows: Controls Workshop M = 17.5 M = 22.7 SS = 100 SS = 124 What type of t-test would you have to conduct in this scenario? Are the data sufficient to conclude that the treatment has a significant effect? Use a two-tailed test with α = .05. State the hypothesis, find the critical region, calculate your test statistic, evaluate your hypothesis then calculate the Cohen’s d measure for this scenario. State whether this is a weak, moderate, or strong effect.
In a science fair project, Emily conducted an experiment in which she tested professional touch therapists to see if they could sense her energy field. She flipped a coin to select either her right hand or her left hand, and then she asked the therapists to identify the selected hand by placing their hand just under Emily's hand without seeing it and without touching it. Among 337 trials, the touch therapists were correct 163 times. Using Emily's sample results, construct a 95% confidence interval estimate of the proportion of correct responses made by touch therapists. (round to 3 decimal places)
The design of controls and instruments affects how easily people can use them. A student project investigated this effect by asking 25 right handed students to turn a knob with their right hands that moved an indicator by screw action. There were two identical instruments, one with a right-hand thread and the other with a left-hand thread. The table given has the data from the student project.1. Calculate and interpret a 90% confidence interval for the mean time advantage of right hand over left hand threads in the setting above.
A researcher takes a random sample of 100 Americans that have never had a pet and a separate random sample of 100 Americans that are current or previous pet owners. She is interested in determining whether there is a difference in the proportion of individuals who believe in the afterlife among these two groups. She observes that 76 of the "never pet owners" and 84 of the "ever pet owners" believe in the afterlife. Determine the margin of error for a confidence interval for the difference in the two appropriate proportions at a 95% confidence level. a. The assumptions necessary to perform the calculation are not satisfied. b. 0.0837 c. 0.0719 d. 0.1103 e. 1.96

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