/*! 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. 50 Sealing your teeth- Many childre... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 4: Q. 50 (page 263)

Sealing your teeth- Many children have their molars sealed to help prevent cavities. In an experiment, 120children aged6鈥�8were randomly assigned to a control group, a group in which sealant was applied and reapplied periodically for 36months, and a group in which fluoride varnish was applied and reapplied periodically for 42months. After 9years, the percent of initially healthy molars with cavities was calculated for each group. Identify the experimental units and the treatments.

Short Answer

Expert verified

The experimental units is fluoridation of water , number of dental cavities and diet and the treatments are to randomize it , control it directly and pair-match .

Step by step solution

01

Given information

We need to find that the experimental units and the treatments .

02

Explanation

The experimental units and factors in this would be fluoridation of water , number of dental cavities and diet.

Here in this case according to experimental design we are given that After9years, the percent of initially healthy molars with cavities was calculated for each group.

The treatment would be to randomize it , control it directly and pair-match .

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

Tonya wanted to estimate the average amount of time that students at her school spend on Facebook each day. She gets an alphabetical roster of students in the school from the registrar鈥檚 office and numbers the students from 1 to 1137. Then Tonya uses a random number generator to pick 30 distinct labels from 1 to 1137. She surveys those 30 students about their Facebook use. Tonya鈥檚 sample is a simple random sample because

a. it was selected using a chance process.

b. it gave every individual the same chance to be selected.

c. it gave every possible sample of size 30 an equal chance to be selected.

d. it doesn鈥檛 involve strata or clusters.

e. it is guaranteed to be representative of the population.

Do you trust the Internet? You want to ask a sample of high school students the question 鈥淗ow much do you trust information about health that you find on the Internet鈥攁 great deal, somewhat, not much, or not at all?鈥� You try out this and other questions on a pilot group of 5students chosen from your class.

a. Explain how you would use a line of Table D to choose an SRS of 5students from the following list.

b. Use line 107to select the sample. Show how you use each of the digits.

Apartment living You are planning a report on apartment living in a college town. You decide to select three apartment complexes at random for in-depth interviews with residents.

a. Explain how you would use a line of Table D to choose an SRS of 3complexes from the following list.

b. Use line 117to select the sample. Show how you use each of the digits.

I work out a lot Are people influenced by what others say? Michael conducted an experiment in front of a popular gym. As people entered, he asked them how many days they typically work out per week. As he asked the question, he showed the subjects one of two clipboards, determined at random. Clipboard A had the question and many responses written down, where the majority of responses were6or7days per week. Clipboard B was the same, except most of the responses were1or2days per week. The mean response for the Clipboard A group was4.68and the mean response for the Clipboard B group was4.21.

a. Calculate the difference (Clipboard A 鈥� Clipboard B) in the mean number of days for the two groups. One hundred trials of a simulation were performed to see what differences in means would occur due only to chance variation in the random assignment, assuming that the responses on the clipboard don鈥檛 matter. The results are shown in the dotplot.

b. There is one dot at0.72. Explain what this dot means in this context.

c. Use the results of the simulation to determine if the difference in means from part (a) is statistically significant. Explain your reasoning.

The Willowbrook and hepatitis Bstudies In the 1960s, children entering the Willowbrook State School, an institution for the intellectually disabled on Staten Island in New York, were deliberately infected with hepatitis. The researchers argued that almost all children in the institution quickly become infected anyway. The studies showed for the first time that two strains of hepatitis existed. This finding contributed to the development of effective vaccines. Despite these valuable results, the Willowbrook studies are now considered an example of unethical research. Explain why, according to current ethical standards, useful results are not enough to allow a study.
See all solutions

Recommended explanations on Math Textbooks

Discrete Mathematics

Read Explanation

Probability and Statistics

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Calculus

Read Explanation

Decision Maths

Read Explanation

Logic and Functions

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.