/*! 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 AP1.7. The owner of a chain of supermar... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 4: Q AP1.7. (page 277)

The owner of a chain of supermarkets notices that there is a positive correlation between the sales of beer and the sales of ice cream over the course of the previous year. During seasons when sales of beer were above average, sales of ice cream also tended to be above average. Likewise, during seasons when sales of beer were below average, sales of ice cream also tended to be below average. Which of the following would be a valid conclusion from these facts?

(a) Sales records must be in error. There should be no association between beer and ice cream sales.

(b) Evidently, for a significant proportion of customers of these supermarkets, drinking beer causes a desire for ice cream, or eating ice cream causes a thirst for beer.

(c) A scatterplot of monthly ice cream sales versus monthly beer sales would show that a straight line describes the pattern in the plot, but it would have to be a horizontal line.

(d) There is a clear negative association between beer sales and ice cream sales.

(e) The positive correlation is most likely a result of the lurking variable temperature; that is, as temperatures increase, so do both beer sales and ice cream sales.

Short Answer

Expert verified

The correct option is (e).

Step by step solution

01

Given information

Type of correlation between the sale of beer and sale of ice-cream is positive.

02

Concept

The correlation coefficient indicates the degree to which the two variables are linearly related.

03

Explanation

The relationship between beer and ice cream sales is good. The linear relationship between the variables is defined by correlation. However, correlation does not imply causation, which means that a change in one variable's sale is not caused by another. However, the change could be due to another factor that causes the sales to behave similarly. In the summer, ice cream is in high demand. Beer is also commonly consumed in the summer. As a result, the most common reason of positive correlation is temperature (which acts as a lurking variable).

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

Each of the following is a source of error in a sample survey. Label each as sampling error or non sampling error, and explain your answers.

(a) The telephone directory is used as a sampling frame.

(b) The person cannot be contacted in five calls.

(c) Interviewers choose people walking by on the sidewalk to interview.

2. A survey paid for by makers of disposable diapers found that 84% of the sample opposed banning disposable diapers. Here is the actual question:

Headache relief Doctors identify 鈥渃hronic tension- type headaches鈥� as headaches that occur almost daily for at least six months. Can antidepressant medications or stress management training reduce the number and severity of these headaches? Are both together more effective than either alone? Investigators compared four treatments: antidepressant alone, placebo alone, antidepressant plus stress management, and placebo plus stress management. The headache sufferers named in the following table have agreed to participate in the study.

(a) Outline the design of the experiment. What is this type of design called?

(b) Explain how you would randomly assign the subjects to the four treatment groups. Then carry out your random assignment.

The ABC program Nightline once asked whether the United Nations should continue to have its headquarters in the United States. Viewers were invited to call one telephone number to respond 鈥淵es鈥� and another for 鈥淣o.鈥� There was a charge for calling either number. More than 186,000 callers responded, and 67% said 鈥淣o.鈥�

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?

Sleep debt (3.2)A researcher reported that the average teenager needs 9.3 hours of sleep per night but gets only 6.3hours.17By the end of a 5-day school week, a teenager would accumulate about 15 hours of 鈥渟leep debt.鈥� Students in a high school statistics class were skeptical, so they gathered data on the amount of sleep debt (in hours) accumulated over time (in days) by a random sample of 25high school students. The resulting least-squares regression equation for their data is Sleepdebt铃�=2.23+3.17(days). Do the students have reason to be skeptical of the research study鈥檚 reported results? Explain.
See all solutions

Recommended explanations on Math Textbooks

Probability and Statistics

Read Explanation

Mechanics Maths

Read Explanation

Logic and Functions

Read Explanation

Geometry

Read Explanation

Statistics

Read Explanation

Decision Maths

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.