/*! 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 81. Aw, rats! A nutrition experiment... [FREE SOLUTION] | 91影视

91影视

Aw, rats! A nutrition experimenter intends to compare the weight gain of newly weaned male rats fed Diet A with that of rats fed Diet B. To do this, she will feed each diet to 10 rats. She has available 10rats from one litter and 10rats from a second litter. Rats in the first litter appear to be slightly healthier.

(a) If the 10rats from Litter 1 were fed Diet A, the effects of genetics and diet would be confounded, and the experiment would be biased in favor of Diet A. Explain this statement carefully.

(b) Describe a better design for this experiment.

Short Answer

Expert verified

(a) If rats from one litter are fed diet Aand they gained more weight, it would be difficult to conclude if it is due to genetic health or diet.

(b) Randomized block design would be better.

Step by step solution

01

Given Information

A nutrition expert wants to compare the weight gain of male rats fed with diet A with those fed with diet B. There are ten rats in one litter and ten in other. Rats is first litter are healthier.

02

To explain the statement.

It means that if ten rats from litter 1were given diet A, it would be confounded if it is genetic or diet that gave such results. Experiment would be biased toward Diet A.

03

To implement better design for experiment.

Randomized block design should be used with litter as blocks. Randomly assign half of the rats with diet A and other half to receive diet B. This will allow us to spot the differences in weight gain caused by difference in initial health and genetics.

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

Instant opinion A recent online poll posed the question 鈥淪hould female athletes be paid the same as men for the work they do?鈥欌 In all, 13,147(44%)said 鈥淵es,鈥欌 15,182(50%)said 鈥淣o,鈥欌 and the remaining 1448 said, 鈥淒on鈥檛 know.鈥 In spite of the large sample size for this survey, we can鈥檛 trust the result. Why not?

Comparing cancer treatments The progress of a type of cancer differs in women and men. Researchers want to design an experiment to compare three therapies for this cancer. They recruit 500male and 300female patients who are willing to serve as subjects.

(a) Which are the blocks in this experiment: the cancer therapies or the two sexes? Why?

(b) What are the advantages of a randomized block design over a completely randomized design using these 800subjects?

(c) Suppose the researchers had 800male and no female subjects available for the study. What advantage would this offer? What disadvantage?

Prayer and meditation You read in a magazine that 鈥渘onphysical treatments such as meditation and prayer have been shown to be effective in controlled scientific studies for such ailments as high blood pressure, insomnia, ulcers, and asthma.鈥 Explain in simple language what the article means by 鈥渃ontrolled scientific studies.鈥 Why can such studies provide good evidence that meditation is an effective

treatment for high blood pressure?

Explain it to the congresswoman You are on the staff of a member of Congress who is considering a bill that would provide government-sponsored insurance for nursing-home care. You report that 1128 letters have been received on the issue, of which 871 oppose the legislation. 鈥淚鈥檓 surprised that most of my constituents oppose the bill. I thought it would be quite popular,鈥 says the congresswoman. Are you convinced that a majority of the voters oppose the bill? How would you explain the statistical issue to the congresswoman?

Internet telephone calls You can use Voice over Internet Protocol (VoIP) to make long-distance

telephone calls over the Internet. How will the cost affect the use of this service? A university plans an experiment to find out. It will offer the service to all 350 students in one of its dormitories. Some students will pay a low flat rate. Others will pay higher rates at peak periods and very low rates off-peak. The university is interested in the amount and time of use and inthe effect on the congestion of the network.

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.