Researchers would like to investigate whether the time of the exam could affect students'performance on a test. They randomly select 120 students and let 50 of them take exams in themorning whereas 70 of them tested in the afternoon. Assume the 120 students have similar skillsand the exams are of similar difficulties.The researchers want to do a statistical test to understand if the mean morning test score is in factdifferent from the mean afternoon test score session.a) Which of the following inference procedure they should choose [Select ]b) What is the most appropriate null hypothesis for this test?[ Select ]c) The p-value for this is 0.893. How would the researcher interpret this p-value? Is there evidencethat there is a difference in mean morning test scores and afternoon test scores?[ Select ]

Given : Morning : Number of students = 50 Afternoon : Number of students = 70

Answered: Researchers would like to investigate…

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 study was done to determine whether the proportion of women who had accidents on Friday the 13th was greater than the proportion of men who had accidents on Friday the 13th. To find out, a random sample was taken of 2,000 individuals. Each individual was asked their gender and whether they had been involved in an accident on Friday the 13th. a)What is the explanatory variable, and is it quantitative or categorical? b)What is the response variable, and is it quantitative or categorical? c)What procedure should be used for this test?
Suppose a consumer group suspects that the proportion of households that have threeor more cell phones is 39%. A cell phone company has reason to believe that the proportion isnot 39%. Before they start a big advertising campaign, they conduct a hypothesis test. Theirmarketing people survey 186 households with the result that 93 of the households have three ormore cell phones. Conduct a hypothesis test to test the cell phone company’s belief at the 5%significance level. show all steps
Suppose you want to find out how many people support Policy X. A standard polling approach is to just ask N many people whether or not they support Policy X, and take the fraction of people who say yes as an estimate of the probability that any one person supports the policy. Suppose that the probability someone supports the policy is p, which you do not know. Let îy be the number of people polled who supported the policy, divided by the total number of people polled N. However, a problem with polling is whether or not people are willing to answer honestly. If a question might be viewed as shameful or embarrassing (about politics, sexual activity, or whatever people are sensitive about), they may be reluctant to answer honestly. A potential solution to this is the following: suppose that 'YES' is the embarrassing or socially shameful answer; give the people you are polling the following instructions: flip a coin privately, and if it comes up heads answer honestly, but if it comes up…
Christine, a researcher in psychology and biobehavioral health, believes that city residents and residents of rural areas differ in how appealing they find owning a cat. A random sample of 109 people who live in San Antonio were surveyed and 59 identified themselves as a "cat person." A random sample of 108 people who live in the surrounding rural area were selected and 72 identified themselves as a "cat person." Conduct an appropriate hypothesis test at the a = 0.1 significance level to test Christine's claim. Round answers to 4 decimal places where appropriate. a. State the null and alternative hypotheses. Ho: p. H₁: p. b. What is the appropriate distribution to use for the hypothesis test? Z (Normal) c. Find the test statistic. Test Statistic: -1.9593 X d. Determine the P-value: op. P-value: 0.0501 X O p.
A student organization reports that, of a random sample of 300 college undergraduates, 95% attend all their classes during the first week of the semester and 15% did not attend all their classes during the first week. We know there is a mistake in this report because O A stratified sample would have been less prone to error O It's very unlikely that 15% of students didn't attend all their classes during the first week O There is always a possibility of response bias O 95% plus 15% adds up to more than 100%
To apply the two-sample t procedures, use Option 1 if you have technology that implements that method. Otherwise, use Option 2. Researchers gave 40 index cards to a waitress at an Italian restaurant in New Jersey. Before delivering the bill to each customer, the waitress randomly selected a card and wrote on the bill the same message that was printed on the index card. Twenty of the cards had the message "The weather is supposed to be really good tomorrow. I hope you enjoy the day!" Another 20 cards contained the message "The weather is supposed to be not so good tomorrow. I hope you enjoy the day anyway!" After the customers left, the waitress recorded the amount of the tip (percent of bill) before taxes. Here are the tips for those receiving the good-weather message. 21.0 18.8 20.3 20.9 21.9 23.7 22.8 25.2 22.7 20.8 25.1 22.3 27.3 21.0 22.5 24.2 21.3 22.3 22.0 23.2 The tips for the 20 customers who received the bad-weather message are below. 19.3 18.8 16.1 17.1 14.4 18.0 19.1 19.4…
The school district sets up two locations to help students with technical difficulties over the summer. They believe the technicians they have assigned to location 2 are being lazy and not helping students as much as they should be so they take a random sample of 15 students from each of the two locations and ask if their technical issue had been resolved (over 200 students had asked for assistance at each location). Twelve of the 15 students from location 1 reported their technical issue had been resolved and 8 of the 15 students from location 2 reported their technical issue had been resolved. Is this convincing evidence that the technicians from location 2 are being lazy and not helping students as much as those from location 1?
A survey of 200 people was taken to determine whether distance from voting center was related to the likelihood of voting. Based on these results, does it appear that these two variables are related at the 10% level of significance?
chapter 11
Past studies have indicated that the percentage of smokers was estimated to be about 34%. Given the new smoking cessation programs that have been implemented, you now believe that the percentage of smokers has reduced. You randomly surveyed 1807 people and found that 574 smoke. Use a 0.05 significance level to test the claim that the percentage of smokers has reduced. a) Identify the null and alternative hypotheses? Но: ? H1: ? v b) What type of hypothesis test should you conduct (left-, right-, or two-tailed)? O left-tailed O right-tailed O two-tailed c) Identify the appropriate significance level. d) Calculate your test statistic. Write the result below, and be sure to round your final answer to two decimal places. e) Calculate your p-value. Write the result below, and be sure to round your final answer to four decimal places. f) Do you reject the null hypothesis? O We reject the null hypothesis, since the p-value is less than the significance level. O We reject the null hypothesis,…
A large manufacturing company claims that less than 10% of its customers make a complaint about the company’s products. Test this claim at the 10% significance level, if a survey found that 29 out of a random sample of 320 of the company’s customers made a complaint about the company’s products.
A fitness center piloted two new programs to help people reduce stress levels and maintain a healthy lifestyle. After one month, 112 of the 125 people who volunteered for a program in mindfulness reported a reduction in stress levels, and 110 of the 135 people who volunteered for a yoga program reported a reduction in stress levels. The fitness center wants to investigate whether there is a significant difference between the proportions of all people in the two programs who would report reductions in stress levels. Have the conditions for inference been met? No, because the samples were not selected or assigned using a random method. Answer A: No, because the samples were not selected or assigned using a random method. A No, because the sizes of the samples are too large compared to the size of the population. Answer B: No, because the sizes of the samples are too large compared to the size of the population. B No, because the normality of the sampling…

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