/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q. 51. Sorting the music Student resear... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Sorting the music Student researchers Adam, Edward, and Kian wondered

if music would affect performance for certain tasks. To find out, they had student volunteers sort a shuffled set of 26 playing cards by face value and by color. Nineteen of the 38 volunteers were randomly assigned to listen to music during the sorting, while the others listened to no music. Here are parallel boxplots of the time in seconds that it took to sort the cards for the students in each group:

Do these data give convincing evidence of a difference in the true mean sorting times at the α=0.103051526=0.200=20.0%α=0.10significance level?

a. State appropriate hypotheses for performing a significance test. Be sure to define the parameters of interest.

b. Check if the conditions for performing the test are met.

Short Answer

Expert verified

Part a) The hypothesis is

H0:μ1=μ2Ha:μ1notequaltoμ2

Part b) All conditions are not met.

Step by step solution

01

Part a) Step 1: Explanation

The given claim is that a difference in the means.

Now we must determine the most appropriate hypotheses for a significance test.

As a result, either the null hypothesis or the alternative hypothesis is the claim. According to the null hypothesis, the population proportions are equal. If the claim is the null hypothesis, the alternative hypothesis is the polar opposite of the null hypothesis.

Therefore, the appropriate hypotheses for this are:

H0:μ1=μ2Ha:μ1notequaltoμ2

Where we have,

μ1=the true average sorting time of music listeners.

μ2= the true mean sorting time of non-music listeners.

02

Part b) Step 1: Explanation

There are three requirements that must be met:

Because the volunteers were assigned to treatment at random, it is satisfactory.

Independent: It is satisfying because the 19people make up less than 10%of the total population.

Normal: It is not satisfactory because the sample size for no music is small, and the distribution of No music is not approximately Normal due to a strong rightward skewed distribution.

As a result, all of the conditions are not met because the large sample condition is not met, and a hypothesis test for the mean difference is not appropriate.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Have a ball! Can students throw a baseball farther than a softball? To find out, researchers conducted a study involving 24randomly selected students from a large high school. After warming up, each student threw a baseball as far as he or she could and threw a softball as far as he she could, in a random order. The distance in yards for each throw was recorded. Here are the data, along with the difference (Baseball – Softball) in distance thrown, for each student:

a. Explain why these are paired data.

b. A boxplot of the differences is shown. Explain how the graph gives some evidence that students like these can throw a baseball farther than a softball.

c. State appropriate hypotheses for performing a test about the true mean difference. Be sure to define any parameter(s) you use.

d. Explain why the Normal/Large Sample condition is not met in this case. The mean difference (Baseball−Softball) in distance thrown for these 24students is xdiff = 6.54yards. Is this a surprisingly large result if the null hypothesis is true? To find out, we can perform a simulation assuming that students have the same ability to throw a baseball and a softball. For each student, write the two distances thrown on different note cards. Shuffle the two cards and designate one distance to baseball and one distance to softball. Then subtract the two distances (Baseball−Softball) . Do this for all the students and find the simulated mean difference. Repeat many times. Here are the results of 100trials of this simulation

e. Use the results of the simulation to estimate the P-value. What conclusion would you draw ?

Treating AIDS The drug AZT was the first drug that seemed effective in delaying

the onset of AIDS. Evidence for AZT’s effectiveness came from a large randomized

comparative experiment. The subjects were 870volunteers who were infected with HIV,

the virus that causes AIDS, but did not yet have AIDS. The study assigned 435of the

subjects at random to take 500milligrams of AZT each day and another 435to take a

placebo. At the end of the study, 38of the placebo subjects and 17of the AZT subjects

had developed AIDS.

a. Do the data provide convincing evidence at the α=0.05level that taking AZT lowers the proportion of infected people like the ones in this study

who will develop AIDS in a given period of time?

b. Describe a Type I error and a Type II error in this setting and give a consequence of

each error.

A large toy company introduces many new toys to its product line each year. The

company wants to predict the demand as measured by y, first-year sales (in millions of dollars) using x, awareness of the product (as measured by the percent of customers who had heard of the product by the end of the second month after its introduction). A random sample of 65new products was taken, and a correlation of 0.96was computed. Which of the following is true?

a. The least-squares regression line accurately predicts first-year sales 96% of the time.

b. About 92% of the time, the percent of people who have heard of the product by the end of the second month will correctly predict first-year sales.

c. About 92% of first-year sales can be accounted for by the percent of people who have heard of the product by the end of the second month.

d. For each increase of 1% in awareness of the new product, the predicted sales will go up by 0.96 million dollars.

e. About 92% of the variation in first-year sales can be accounted for by the leastsquares regression line with the percent of people who have heard of the product by the end of the second month as the explanatory variable.

Children make choices Refer to Exercise 15.

a. Explain why the sample results give some evidence for the alternative hypothesis.

b. Calculate the standardized test statistic and P-value.

c. What conclusion would you make?

The P-value for the stated hypotheses is 0.002Interpret this value in the context of this study.

a. Assuming that the true mean road rage score is the same for males and females, there is a 0.002probability of getting a difference in sample means equal to the one observed in this study.

b. Assuming that the true mean road rage score is the same for males and females, there is a 0.002 probability of getting a difference in sample means at least as large in either direction as the one observed in this study.

c. Assuming that the true mean road rage score is different for males and females, there is a 0.002 probability of getting a difference in sample means at least as large in either direction as the one observed in this study.

d. Assuming that the true mean road rage score is the same for males and females, there is a 0.002 probability that the null hypothesis is true.

e. Assuming that the true mean road rage score is the same for males and females, there is a 0.002 probability that the alternative hypothesis is true.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.