A sociologist is studying the effect of having children within the first two years of marriageon the divorce rate. Using hospital birth records, she selects a random sample of 200couples that had a child within the first two years of marriage. Following up on thesecouples, she finds that 80 couples are divorced within five years.Use Scenario 8-4. A 90% confidence interval for the proportion p of all couples that had achild within the first two years of marriage and are divorced within five years is0.40 + 0.044.aO b0.40 + 0.004.0.40 + 0.057.O d0.40 ± 0.035.

It is given that the sample size (n) is 200 and x=80.

Answered: A sociologist is studying the effect of…

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 graduate student is interested in how viewing different types of scenes affects working memory. For his study, he selects a random sample of 36 adults. The subjects complete a series of working memory tests before and after walking in an urban setting. Before the walk, the mean score on the test of working memory was 9.1. After the walk, the mean score was 1.4 higher. The graduate student has no presupposed assumptions about how viewing different types of scenes affects working memory, so he formulates the null and alternative hypotheses as: H00 : μDD = 0 H11 : μDD ≠ 0 Assume that the data satisfy all of the required assumptions for a repeated-measures t test. The graduate student calculates the following statistics for his hypothesis test: Mean difference (MDD) 1.4 Estimated population standard deviation of the differences (s) 1.6 Estimated standard error of the mean differences (sMDMD) 0.2667 Degrees of freedom (df) 35 The t statistic 5.25 The critical values of t…
The Interpersonal Reactivity Index is a survey designed to assess four different types of empathy. One type of empathy, called Empathetic Concern, measures the tendency to feel sympathy and compassion for people who are less fortunate. The index ranges from 0 (less empathetic) to 28 (more empathetic). The following data, representing random samples of 8 males and 8 females, are consistent with results reported in psychological studies. Boxplots show that it is reasonable to assume that the populations are approximately normal and have equal variances. Males 13 20 14 16 13 26 21 23 Females 22 20 26 25 28 24 16 19 Can you conclude that there is a difference in mean empathy score between men and women? Use a=0.03. (1) Critical Values (Round off to 3 decimal places): (2) Test Statistic (Round off to 2 decimal places): (3) Conclusion: (Type 'Reject HO' or 'Fail to Reject HO')
The Wisconsin Fish and Game Department stocked a lake with 30% catfish, 15 % bass, 40% bluegill, and 15% Northern Pike. Five years later they took a random sample of 500 fish from the lake and found 120 catfish, 85 bass, 220 bluegill, and 75 Northern Pike. At the 5% level of significance, can we show that the distribution of fish changed over the 5-year interval? State and test appropriate hypotheses. State conclusions.
Researchers investigate how the presence of cell phones influence the quality of human interaction. Subjects are randomly selected from a population and divided into an experimental group that is asked to leave their phones in the front of the room and a control group that are not asked to leave their cell phones at the front of the room. Subjects are left alone for 10 minutes and then asked to take a survey designed to measure quality of interactions they had with others in the experiment. What statistical test is appropriate?
As a hospital administrator of a large hospital, you are concerned with the absenteeism among nurses' aides. The issue has been raised by registered nurses, who feel they often have to perform work normally done by their aides. To get the facts, absenteeism data were gathered for the last three weeks, which is considered a representative period for future conditions. After taking random samples of 64 personnel files each day, the following data were produced Day 1 2 3 4 Aides Absent 5 4 2 6 a Day 6 7 8 9 10 Aides Absent 6 7 9 3 7 Day Aides Absent 11 12 13 (Enter your responses rounded to The upper control limit is and the lower control limit is three decimal places. If your answer for the lower control limit is negative, enter this value as 0.) 14 15 6 8 10 1 2 Because your assessment of absenteeism is likely to come under careful scrutiny, you would like a type I error of only 1 percent. You want to be sure to identify any instances of unusual absences. If some are present, you will…
Teenagers who do not sleep well or long enough may have a higher risk of raised blood pressure, which could lead to cardiovascular disease later in life. The odds of raised blood pressure increase 3.5 times for those who have trouble falling asleep at night or who wake up too early and 2.5 times for those with sleeping periods of fewer than 6.5 hours. A health psychologist is interested in studying teenagers who have diastolic blood pressure scores in the top 20%. Diastolic blood pressure scores for teenagers follow a normal distribution with μ = 72 and σ = 10. Use the Distributions tool to help answer the questions that follow. The minimum z-score necessary to be in the top 20% of the diastolic blood pressure distribution is z =0.842 . Use this z-score to determine X, the corresponding diastolic blood pressure score. X = 80.42 This score, X, is the 80th percentile of diastolic blood pressure scores among teenagers. The percentile rank of this score is 80%…
Acne is a common skin disease that affects most adolescents and can continue into adulthood. A study compared the effectiveness of three acne treatments and a placebo, all in gel form, applied twice daily for 12 weeks. The study's 517 teenage volunteers were randomly assigned to one of the four treatments. Success was assessed as clear or almost clear skin at the end of the 12 week period. The results of the study can be seen in the table below. Using the appropriate statistical test, determine if there is significant evidence that the four treatments perform differently. If so, how do they compare.
According to the U.S. Department of Transportation’s Air Travel Consumer Report, the nation’s 12 largest airlines recorded an on-time arrival percentage of 77.4% in 2001. Of interest is to estimate the mean delay time for the 22.6% of all flights that did not arrive on time during 2013. A simple random sample of 28 late arriving flights was selected, and the mean delay time of this sample of 28 flights was 14.2 minutes, with a sample standard deviation of s= 6.4 minutes. Use this information to calculate and interpret a 98% confidence interval for the mean delay time for all flights that did not arrive on time during 2013.
15. Pain after surgery: In a random sample of 50 patients undergoing a standard surgical procedure, 15 required medication for postoperative pain. In a random sample of 90 patients undergoing a new procedure, only 16 required pain medication. a. Construct a 95% confidence interval for the difference in the proportions of patients needing pain medication between the old and new procedures. b. A physician claims that the proportion of patients who need pain medication is the same for both procedures. Does the confidence interval contradict this claim? 16
A credit score is used by credit agencies (such as mortgage companies and banks) to assess the creditworthiness of individuals. Values range from 300 to 850, with a credit score over 700 considered to be a quality credit risk. According to a survey, the mean credit score is 710.6. A credit analyst wondered whether high-income individuals (incomes in excess of $100,000 per year) had higher credit scores. He obtained a random sample of 48 high-income individuals and found the sample mean credit score to be 723.6 with a standard deviation of 81.2. Conduct the appropriate test to determine if high-income individuals have higher credit scores at the a = 0.10 level of significance. Click the icon to view the table of critical t-values. State the null and alternative hypotheses. Fill in the correct answers below. Ho: Hyi H (Type integers or decimals. Do not round.) Identify the t-statistic. to = (Round to two decimal places as needed.) Approximate the P-value. The P-value is in the range Make…
The state highway department is studying traffic patterns on one of the busiest highways in the state. As part of the study. the department needs to estimate the average number of vehicles that pass an intersection each day. One of the department's officer (Officer A) claims that on average, more than 15,000 cars passing the intersection. On the other hand. Officer B claims that on average, 18,000 cars passing the intersection. Meanwhile, a random sample of 64 days gives a sample mean of 14,205 cars and a sample standard deviation of 1,010 cars. Test both claim at 0.05 level of significance. Use the critical value approach and show the complete calculation steps for each testing. Whose claim is true? Testing Officer A's claim Step 1: State the hypotheses Step 2: Find critical value and state the decision rule Step 3: Compute the test value Step 4: Make decision Step 5: Conclusion Testing Officer B's claim Step 1: State the hypotheses Step 2: Find critical value and state the decision…
Mood variation is related to photoperiod in some people, and the likelihood of depression increases in the winter months. As a result, people often assume that suicide rates increase in winter. A study in Finland (Valtonen et al. 2006) divided the year 1997 into equal halves and compared the number of suicides in “winter” (24 September to 19 March) and “summer” (remainder of year). Out of a total of 1636 suicides, 766 were in winter and 870 were in the summer. Based on these data, estimate the proportion of suicides that occurred in winter, assuming that the suicides were independent. Are the data compatible with a greater suicide rate in winter than summer, based on a 95% confidence interval?

SEE MORE QUESTIONS

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