APPLIED STAT.IN BUS.+ECONOMICS
6th Edition
ISBN: 9781259957598
Author: DOANE
Publisher: RENT MCG
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Question
Chapter 10, Problem 84CE
a.
To determine
Construct a 95% confidence interval for the difference in proportions and describe the conclusion.
b.
To determine
Check whether the normality of
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A group of researchers wants to know whether men (population 1) are more likely than women
(population 2) to contract a novel coronavirus. They surveyed two random samples of 490 men
and 480 women who were tested and found that 52 men and 91 women in the samples tested
positive.
Can you conclude that the proportion of positive tests among men is less than the proportion of
positive tests among women? Use level of significance 5%.
Procedure: Select an answer
Step 1. Hypotheses Set-Up:
where Select an answer
the
Ho: Select an answer
Select an answer
and the
units are Select an answer
Ha: Select an answer
, and the test is Select an answer
Step 2. The significance level a
(Round the answer to 3
Step 3. Compute the value of the test statistic: Select an answer
decimal places)
Step 4. Testing Procedure: (Round the answers to 3 decimal places)
CVA
PVA
Provide the critical value(s) for the Rejection Region:
Compute the P-value of the test
statistic:
left CV is
and right CV is
P-value is
Step…
Need help asap! Thanks!!
A well-known psychologist has established what she calls her Generalized Anxiety (GA) scale. The GA scale, which is a scale from 0 to 10, measures the "general
anxiety" of an individual, with higher GA scores corresponding to more anxiety.
We'd like to make predictions about individuals' sleep behavior based on their GA scores. We've collected bivariate data that give the GA score (denoted by x)
and the number of hours of sleep last night (denoted by y) for each of the 11 adults participating in a study. The least-squares regression equation for our data
is y = 8.92-0.25x. We have used this equation to predict tonight's sleep time for a woman whose GA score is 6.2. We're now interested in both a prediction
interval for her sleep time and a confidence interval for the mean sleep time of individuals with her GA score. We have computed the following for our data.
• mean square error (MSE)≈ 0.601
(6.2-x)²
●
11
+
11
2
Σ (x₁ - x)²
i=1
≈ 0.1110, where x₁, x2,
Lower limit:
X11
Based on this…
Chapter 10 Solutions
APPLIED STAT.IN BUS.+ECONOMICS
Ch. 10.2 - Do a two-sample test for equality of means...Ch. 10.2 - Repeat the previous exercise, assuming unequal...Ch. 10.2 - Is there a difference in the average number of...Ch. 10.2 - Prob. 4SECh. 10.2 - Prob. 5SECh. 10.2 - Prob. 6SECh. 10.2 - Prob. 7SECh. 10.2 - On a random basis, Bob buys a small take-out...Ch. 10.2 - For a marketing class term project, Bob is...Ch. 10.3 - A special bumper was installed on selected...
Ch. 10.3 - In trials of an experimental internet-based method...Ch. 10.3 - Construct a 95 percent confidence interval for the...Ch. 10.4 - (a) At = .05, does the following sample show that...Ch. 10.4 - An experimental surgical procedure is being...Ch. 10.4 - Blue Box is testing a new half price on Tuesday...Ch. 10.4 - The U.S. governments Cash for Clunkers program...Ch. 10.4 - Prob. 17SECh. 10.4 - Below is a random sample of shoe sizes for 12...Ch. 10.4 - A newly installed automatic gate system was being...Ch. 10.5 - Calculate the test statistic and p-value for a...Ch. 10.5 - Prob. 21SECh. 10.5 - Prob. 22SECh. 10.5 - Prob. 23SECh. 10.5 - Prob. 24SECh. 10.5 - Prob. 25SECh. 10.5 - A survey of 100 mayonnaise purchasers showed that...Ch. 10.5 - Prob. 27SECh. 10.5 - Prob. 28SECh. 10.5 - When tested for compliance with Sarbanes-Oxley...Ch. 10.5 - Prob. 30SECh. 10.5 - From a telephone log, an executive finds that 36...Ch. 10.5 - Prob. 32SECh. 10.6 - The American Bankers Association reported that, in...Ch. 10.6 - A study showed that 36 of 72 cell phone users with...Ch. 10.6 - Prob. 35SECh. 10.7 - Which samples show unequal variances? Use = .10...Ch. 10.7 - Prob. 37SECh. 10.7 - Prob. 38SECh. 10.7 - A manufacturing process drills holes in sheet...Ch. 10.7 - Examine the data below showing the weights (in...Ch. 10 - (a) Explain why two samples from the same...Ch. 10 - (a) In a two-sample test of proportions, what is a...Ch. 10 - List the three cases for a test comparing two...Ch. 10 - Consider Case 1 (known variances) in the test...Ch. 10 - Consider Case 2 (unknown but equal variances) in...Ch. 10 - Consider Case 3 (unknown and unequal variances) in...Ch. 10 - Why is it a good idea to use a computer program...Ch. 10 - (a) Explain why the paired t test for dependent...Ch. 10 - Explain how a difference in means could be...Ch. 10 - (a) Why do we use an F test? (b) When two...Ch. 10 - (a) In an F test for two variances, explain how to...Ch. 10 - Prob. 41CECh. 10 - In an early home game, an NBA team made 66 of...Ch. 10 - Prob. 43CECh. 10 - A recent study found that 202 women held board...Ch. 10 - A study of the Fortune 100 board of director...Ch. 10 - Prob. 46CECh. 10 - How many full-page advertisements are found in a...Ch. 10 - eShopNet, an online clothing retailer, is testing...Ch. 10 - After John F. Kennedy Jr. was killed in an...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - At a University of Colorado womens home basketball...Ch. 10 - A ski resort tracks the proportion of seasonal...Ch. 10 - Does a follow-up reminder increase the renewal...Ch. 10 - A study revealed that the 30-day readmission rate...Ch. 10 - In a marketing class, 44 student members of...Ch. 10 - In San Francisco, a sample of 3,200 wireless...Ch. 10 - Prob. 57CECh. 10 - Prob. 58CECh. 10 - Prob. 59CECh. 10 - Prob. 60CECh. 10 - Prob. 61CECh. 10 - Prob. 62CECh. 10 - In a 15-day survey of air pollution in two...Ch. 10 - Prob. 64CECh. 10 - Do male and female school superintendents earn the...Ch. 10 - The average take-out order size for Ashoka Curry...Ch. 10 - Cash withdrawals from a college credit union for a...Ch. 10 - In Mini Case 10.2, we found that the mean methane...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - A ski company in Vail owns two ski shops, one on...Ch. 10 - Emergency room arrivals in a large hospital showed...Ch. 10 - Concerned about graffiti, mayors of nine suburban...Ch. 10 - A certain company will purchase the house of any...Ch. 10 - Nine homes are chosen at random from real estate...Ch. 10 - Prob. 75CECh. 10 - Prob. 76CECh. 10 - Prob. 77CECh. 10 - Is there a difference between the variance in ages...Ch. 10 - A survey of 100 mayonnaise purchasers showed that...Ch. 10 - A 20-minute consumer survey mailed to 500 adults...Ch. 10 - One group of accounting students used simulation...Ch. 10 - Advertisers fear that users of DVRs (digital video...Ch. 10 - In preliminary tests of a vaccine that may help...Ch. 10 - Prob. 84CECh. 10 - Male and female students in a finance class were...Ch. 10 - Prob. 86CECh. 10 - A retailer compared the frequency of customer...Ch. 10 - Streeling University surveyed a random sample of...Ch. 10 - The Fischer Theatre compared attendance at its...Ch. 10 - Random samples of tires being replaced by a car...Ch. 10 - Count the number of two-door vehicles among 50...Ch. 10 - Which statement is not correct? Explain. a. The...Ch. 10 - Match each statement to the correct property of an...Ch. 10 - Concerning confidence intervals, which statement...Ch. 10 - Prob. 4ERQCh. 10 - Prob. 5ERQCh. 10 - Prob. 6ERQCh. 10 - Prob. 7ERQCh. 10 - Prob. 8ERQCh. 10 - The process that produces Sonora Bars (a type of...Ch. 10 - Prob. 10ERQCh. 10 - Prob. 11ERQCh. 10 - Last month, 85 percent of the visitors to the...Ch. 10 - Weights of 12 randomly chosen Sonora Bars (a type...Ch. 10 - In a random sample of 200 Colorado residents, 150...Ch. 10 - Five students in a large lecture class compared...Ch. 10 - Prob. 16ERQCh. 10 - Prob. 17ERQ
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- A medical journal reported on an experiment intended to see if a certain drug could be used as a treatment for the eating disorder anorexia nervosa. The subjects were randomly divided into two groups. Of the 98 who received this drug, 70 were deemed healthy a year later, compared to 50 of the 88 who got the placebo. What is the population for this study? Is this an experimental study? Explain. What is the explanatory variable? What is the response variable? Complete the 2x2 table of counts.arrow_forwardA headache medicine is tested on an experimental group of 50 patients who have headaches. Out of these people, 37 of them say they felt better when taking the medicine. A fake pill (placebo) is given to 50 different patients, of whom 27 say they felt better after taking the "medicine". Is this enough evidence to show that a higher percentage of people in the experimental group were cured, compared to the control group? (Use a = .01) Type of Test: Hypotheses: Test Statistic: P-value: Decision: XC. In a sentence, what can be said about the medicine?arrow_forwardA better drug? In a pilot study, a company's new cholesterol-reducing drug outperforms the currently available drug. If the data provide convincing evi- dence that the mean cholesterol reduction with the new drug is more than 10 milligrams per deciliter of blood (mg/dl) greater than with the current drug, the company will begin the expensive process of mass-producing the new drug. For the 14 subjects who were assigned at random to the current drug, the mean cholesterol reduction was 54.1 mg/dl with a standard deviation of 11.93 mg/dl. For the 15 sub- jects who were randomly assigned to the new drug, the mean cholesterol reduction was 68.7 mg/dl with a standard deviation of 13.3 mg/dl. Graphs of the data reveal no outliers or strong skewness. Carry out an appropriate significance test. What conclusion would you draw? (Note that the null hypothesis is not Ho: μμ2=0.) Based on your conclusion in part (a), could you have made a Type I error or a Type II error? Justify your answer.arrow_forward
- A research study examined the effects of a new drug versus an old drug on hypertension. There were 172 people enrolled in the new drug group, and 125 of them were hypertensive. For the old drug group, 165 people were enrolled and of those, 76 were hypertensive. Was there a difference in the proportion of people who were hypertensive between the new drug and the old drug? Calculate the z or t test statisticarrow_forwardA medical researcher wants to test the effectiveness of a new drug in treating a certain disease. They randomly assigned 100 patients to two groups: one group received the new drug, and the other group received a placebo. After a month, they measured the patients' symptom severity on a scale of 1 to 10. The researcher found that the mean symptom severity score for the group that received the new drug was lower than the mean score for the group that received the placebo. How can the researcher test the hypothesis that the new drug is effective in treating the disease? What statistical test should they use?arrow_forwardThe DASS-21 questionnaire is a validated measure of depression, anxiety, and stress. For the general population, the mean for anxiety is µ = 4.2. Anxiety levels are calculated based on self-reported answers to questions on a scale from 0 through 42, with lower scores indicating lower anxiety. Participants with gastrointestinal issues (specifically inflammatory bowel disease, IBD) completed the DASS-21. Use the data presented below to determine whether having gastrointestinal issues like IBD significantly increases risk for anxiety. Test whether or not the performance of this sample is significantly higher than the normal population using the proper t-test. Here are the data: Anxiety scores: 12, 15, 10, 8, 10, 5, 10, 13, 4, 6 ANALYSES AND UNGRADED OPTIONAL GUIDING QUESTIONS: 1a. Identify the Indep.Variable:__ Dep.Variable:__ Is it the Hypothesis one-tailed or two-tailed?__ Proper t-test statistic:__ Why? _ State Hypotheses mathematically: H0:__ H1:__ State…arrow_forward
- The DASS-21 questionnaire is a validated measure of depression, anxiety, and stress. For the general population, the mean for anxiety is µ = 4.2. Anxiety levels are calculated based on self-reported answers to questions on a scale from 0 through 42, with lower scores indicating lower anxiety. Participants with gastrointestinal issues (specifically inflammatory bowel disease, IBD) completed the DASS-21. Use the data presented below to determine whether having gastrointestinal issues like IBD significantly increases risk for anxiety. Test whether or not the performance of this sample is significantly higher than the normal population using the proper t-test. Here are the data: Anxiety scores: 12, 15, 10, 8, 10, 5, 10, 13, 4, 6 ANALYSES AND UNGRADED OPTIONAL GUIDING QUESTIONS: 1a. Identify the Indep.Variable:__ Dep.Variable:__ Is it the Hypothesis one-tailed or two-tailed?__ Proper t-test statistic:__ Why? _ State Hypotheses mathematically: H0:__ H1:__ State…arrow_forwardThe heart rate variability (HRV) of police officers was the subject of research published in a biology journal. HRV is defined as the variation in the time intervals between heartbeats. A measure of HRV was obtained for each in a sample of 348 police officers from the same city. (The lower the measure of HRV, the more susceptible the officer is to cardiovascular disease.) For the 74 officers diagnosed with hypertension, a 90% confidence interval for the mean HRV was (9.5, 124.2). For the 274 officers that are not hypertensive, a 90% confidence interval for the mean HRV was (141.8,186.2). Use this information to complete parts a through d below. a. What confidence coefficient was used to generate the confidence intervals? Type an integer or a decimal. Do not round) b. Give a practical interpretation of both of the 90% confidence intervals. Use the phrase "90% confident" in your answer. The researchers can be 90% confident that the mean HRV for all hypertensive police officers in the is…arrow_forwardThe heart rate variability (HRV) of police officers was the subject of research published in a biology journal. HRV is defined as the variation in the time intervals between heartbeats. A measure of HRV was obtained for each in a sample of 331 police officers from the same city. (The lower the measure of HRV, the more susceptible the officer is to cardiovascular disease.) For the 76 officers diagnosed with hypertension, a 90% confidence interval for the mean HRV was (7.2,121.3). For the 255 officers that are not hypertensive, a 90% confidence interval for the mean HRV was (141.6,189.9). Use this information to complete parts a through d below. a. What confidence coefficient was used to generate the confidence intervals? (Type an integer or a decimal. Do not round) b. Give a practical interpretation of both of the 90% confidence intervals. Use the phrase '90% confident" in your answer. The researchers can be 90% confident that the Type integers or decimals. Do not round.) V mean HRV for…arrow_forward
- In an observational study it was found that people who had received the flu shot this year had better blood pressure readings, on average, than people who did not. Can it be claimed that the flu shot is the cause of the lower overall blood pressure? Why or why not?arrow_forwardAre seatbelts effective at saving lives? We wish to examine whether or not the use of seatbelts reduces fatalities at the a = 0.01 level of significance. Let pN represent the proportion of non-seatbelt wearing passengers who were involved in a crash and died and py represent the proportion of seatbelt wearing passengers who were involved in a crash and died. NOTE: The data used in this study were obtained through observational study...no experiment was conducted! Which would be correct hypotheses for this test? O Ho:PN = pY, H1:PN > pY Ho: PN = pY, H,:PN Py In a random sample of 321 non-seatbelt wearing passengers involved in a car crash, 30 were killed. In a random sample of 492 seatbelt wearing passengers involved in a car crash, 13 were killed. Find the test statistic (2 decimal places): Give the P-value (4 decimal places - if less than 0.001 answer 0): Which is the correct result: Reject the Null Hypothesis O Do not Reject the Null Hypothesis Which would be the appropriate…arrow_forwardAmong individuals who eat a healthy diet and exercise frequently the point prevalence of hypertension is 0.09. Individuals subject to poverty, making it more difficult for them to eat a healthy diet and exercise frequently, have a 0.31 point prevalence for hypertension. What is the risk difference between the two groups? 0.29 0.76 0.78 0.22arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt
Statistics 4.1 Point Estimators; Author: Dr. Jack L. Jackson II;https://www.youtube.com/watch?v=2MrI0J8XCEE;License: Standard YouTube License, CC-BY
Statistics 101: Point Estimators; Author: Brandon Foltz;https://www.youtube.com/watch?v=4v41z3HwLaM;License: Standard YouTube License, CC-BY
Central limit theorem; Author: 365 Data Science;https://www.youtube.com/watch?v=b5xQmk9veZ4;License: Standard YouTube License, CC-BY
Point Estimate Definition & Example; Author: Prof. Essa;https://www.youtube.com/watch?v=OTVwtvQmSn0;License: Standard Youtube License
Point Estimation; Author: Vamsidhar Ambatipudi;https://www.youtube.com/watch?v=flqhlM2bZWc;License: Standard Youtube License