/*! 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.31 聽A researcher wants to determin... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 10: Q.31 (page 671)

A researcher wants to determine whether or not a five-week crash diet is effective over a long period of time. A random sample of 15 dieters is selected. Each person鈥檚 weight is recorded before starting the diet and one year after it is concluded. Based on the data shown below (weight in pounds), can we conclude that the diet has a long-term effect, that is, that dieters managed to not regain the weight they lost? Include appropriate statistical evidence to justify your answer.

Short Answer

Expert verified

Critical value of t at 0.05level of significance =1.76131

As t<1.76131, we do not reject the null hypothesis and conclude that the five -week crash diet is not effective over a long period of time.

Step by step solution

01

Step 1. given information

We have given the weight of the person before diet and after diet in pounds.

02

Step 2. Simplify

The null and alternative hypothesis is given by :

H0:渭d=0H1:渭d>0

Where is the mean of the deviation.

The test static is given by,

t=dSd(d)~tn-1

Where d is the mean of deviation in the paired sample.

We have to reject the null hypothesis ift>t伪,n-1

now,

And,

The above table is obtained from excel.

The value of test static t=0.312361

Critical value of t at 0.05level of significance =1.76131

As t<1.76131,we do not reject the null hypothesis and conclude that the five -week crash diet is not effective over a long period of time.

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 91影视!

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

In an experiment to learn whether Substance M can help restore memory, the brains of 20rats were treated to damage their memories. The rats were trained to run a maze. After a day, 10rats (determined at random) were given M and 7of them succeeded in the maze. Only 2of the 10control rats were successful. The two-sample z test for 鈥渘o difference鈥� against 鈥渁 significantly higher proportion of the M group succeeds鈥�

(a) gives z=2.25,P<0.02

(b) gives z=2.60,P<0.005

(c) gives z=2.25,P<0.04but not <0.02

(d) should not be used because the Random condition is violated

(e) should not be used because the Normal condition is violated.

Computer gaming Do experienced computer game players earn higher scores when they play with someone present to cheer them on or when they play alone? Fifty teenagers who are experienced at playing a particular computer game have volunteered for a study . We randomly assign 25of them to play the game alone and the other 25to play the game with a supporter present. Each player鈥檚 score is recorded.

(a) Is this a problem with comparing means or comparing proportions? Explain.

(b) What type of study design is being used to produce data?

A random sample of 200 New York State voters included 88 Republicans, while a random sample of 300 California voters produced 141 Republicans. Which of the following represents the 95%confidence interval that should be used to estimate the true difference in the proportions of Republicans in New York State and California?

(a) (0.44-0.47)卤1.96(0.44)(0.56)+(0.47)(0.53)200+300

(b) (0.44-0.47)卤1.96(0.44)(0.56)200+(0.47)(0.53)300

(c) (0.44-0.47)卤1.96(0.44)(0.56)200+(0.47)(0.53)300

(d)(0.44-0.47)卤1.96(0.44)(0.56)+(0.47)(0.53)200+300

(e) (0.44-0.47)卤1.96(045)(0.55)1200+1300

Driving too fast How seriously do people view speeding in comparison with other annoying behaviors?

A large random sample of adults was asked to rate a number of behaviors on a scale of 1 (no problem at all) to 5(very severe problem). Do speeding drivers get a higher average rating than noisy neighbors?

Toyota or Nissan? Are Toyota or Nissan owners more satis铿乪d with their vehicles? Let鈥檚 design a study to 铿乶d out. We鈥檒l select a random sample of 400Toyota owners and a separate random sample of 400Nissan owners. Then we鈥檒l ask each individual in the sample: 鈥淲ould you say that you are generally satis铿乪d with your (Toyota/Nissan) vehicle?鈥�

(a) Is this a problem with comparing means or comparing proportions? Explain.

(b) What type of study design is being used to produce data?
See all solutions

Recommended explanations on Math Textbooks

Theoretical and Mathematical Physics

Read Explanation

Statistics

Read Explanation

Geometry

Read Explanation

Discrete Mathematics

Read Explanation

Probability and Statistics

Read Explanation

Calculus

Read Explanation
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.