Football on TVA Gallup poll conducted telephone interviews with a random sample of 1000adults aged 18and older. Of these, 37%said that football was their favorite sport to watch on television. The margin of error for this estimate is 3.1percentage points.

a. Would you be surprised if a census revealed that 50%of adults in the population would say their favorite sport to watch on TV is football? Explain your answer.

b. Explain how Gallup could decrease the margin of error

Short Answer

Expert verified

A.Yes, I would be surprised if a census revealed that 50%of the population would say their favorite sport to watch on TV is football.

b.Gallup could decrease the margin of error by increasing the sample size.

Step by step solution

01

Part (a) Step 1: Given Information

We are given following information:

Total random samples (age 18and more) =1000

The total number of samples out of 1000whose favorite sport is football to watch on TV is 370.

The margin of error for this estimate is 3.1percentage points.

We need to explain will we be surprised if a census revealed that 50%of the adult population would say their favorite sport to watch on TV is football.

02

Part (a) Step 2: Explanation

Yes, I would be surprised if a census revealed that 50%of the population would say their favorite sport to watch on TV is football. Because we expect the parameter to fall within the range of 33.1%to40.1%, a value of 50%seems unlikely and unusual.

03

Part (b) Step  1: Given Information

We need to explain decrease of margin of error due to Gallup.

04

Part (b) Step 2: Explanation

Gallup could decrease the margin of error by increasing the sample sizes.

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 Vaia!

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

SRS of students? At a party, there are 30 students over age 21 and 20students underage21. You choose at random 3 of those over 21 and separately choose at random 2 of those under 21 to interview about their attitudes toward alcohol. You have given every student at the party the same chance to be interviewed. Is your sample an SRS? Explain your answer.

Consider an experiment to investigate the effectiveness of different insecticides in

controlling pests and their impact on the productivity of tomato plants. What is the best

reason for randomly assigning treatment levels (spraying or not spraying) to the

experimental units (farms)?

a. Random assignment eliminates the effects of other variables, like soil fertility.

b. Random assignment eliminates chance variation in the responses.

c. Random assignment allows researchers to generalize conclusions about the

effectiveness of the insecticides to all farms.

d. Random assignment will tend to average out all other uncontrolled factors such as

soil fertility so that they are not confounded with the treatment effects.

e. Random assignment helps avoid bias due to the placebo effect.

Corn variety 1yielded 140bushels per acre last year at a research farm. This year, corn

variety 2, planted in the same location, yielded only 110bushels per acre. Based on these

results, is it reasonable to conclude that corn variety 1is more productive than corn variety

2?

a. Yes, because 140bushels per acre is greater than 110bushels per acre.

b. Yes, because the study was done at a research farm.

c. No, because there may be other differences between the two years besides the corn

variety.

d. No, because there was no use of a placebo in the experiment.

e. No, because the experiment wasn’t double-blind.

No tipping The owner of a large restaurant is considering a new "no tipping" policy and wants to survey a sample of employees. The policy would add 20% to the cost of food and beverages and the additional revenue would be distributed equally among servers and kitchen staff. Describe how to select a stratified random sample of approximately 30 employees. Explain your choice of strata and why stratified random sampling might be preferred in this context.

Student archaeologists An archaeological dig turns up large numbers of pottery shards,

broken stone tools, and other artifacts. Students working on the project classify each

artifact and assign a number to it. The counts in different categories are important for

understanding the site, so the project director chooses 2%of the artifacts at random and

checks the students’ work. Identify the population and the sample.

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.

Sign-up for free