/*! 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. 12 The correlation between the heig... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 10: Q. 12 (page 668)

The correlation between the heights of fathers and the heights of their (grownup) sons isr=0.52 , both measured in inches. If fathers鈥� heights were measured in feet and sons鈥� heights were measured in furlongs (one furlong equals 7920 inches), the correlation between heights of fathers and heights of sons would be

(a) much smaller than 0.52.

(b) slightly smaller than 0.52.

(c) unchanged; equal to 0.52.

(d) slightly larger than 0.52.

(e) much larger than 0.52.

Short Answer

Expert verified

The answer is an option (c) unchanged; equal to 0.52

Step by step solution

01

Given Information

The correlation between the heights of fathers and the heights of their (grownup) sons is r=0.52, both measured in inches.

And, one furlong equals 7920 inches.

02

Explanation. 

The advantage of correlation is it's a unitless measure. If changing one of the unit measures (from feet to furlongs) resulted in a correlation change, then the value would be arbitrary since we have arbitrarily defined the units. Then, the correlation would never have any practical meaning.

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

44. Tropical flowers Different varieties of the tropical flower Heliconia are fertilized by different species of hummingbirds.

Researchers believe that over time, the lengths of the flowers and the forms of the hummingbirds鈥� beaks have evolved to match each other. Here are data on the lengths in millimeters for random samples of two color varieties of the same species of flower on the island of Dominica:

(a) A Fathom dotplot of the data is shown below. Use the graph to answer these questions:

  • Are the centers of the two groups similar or different? Explain
  • Are the spreads of the two groups similar or different? Explain.

(b) Construct and interpret a 95% confidence interval for the difference in the mean lengths of these two varieties of flowers.
(c) Does the interval support the researchers鈥� belief that the two flower varieties have different average lengths? Explain.

A scatterplot and a least-squares regression line are shown in the figure below. If the labeled point P(20,24)is removed from the data set, which of the following statements is true ?

(a) The slope will decrease, and the correlation will decrease.

(b) The slope will decrease, and the correlation will increase.

(c) The slope will increase, and the correlation will increase.

(d) The slope will increase, and the correlation will decrease.

(e) No conclusion can be drawn since the other coordinates are unknown.

Aspirin prevents blood from clotting and so helps prevent strokes. The Second European Stroke Prevention Study asked whether adding another anti-clotting drug, named dipyridamole, would be more effective for patients who had already had a stroke. Here are the data on strokes and deaths during the two years of the study.

Number ofpatientsNumber ofstrokesAspirin alone1649206Aspirin + dipyridamole1650157

The study was a randomized comparative experiment.

(a) Is there a significant difference in the proportion of strokes between these two treatments? Carry out an appropriate test to help answer this question.

(b) Describe a Type I and a Type II error in this setting. Which is more serious? Explain

Prayer and pregnancy Two hundred women who were about to undergo IVF served as subjects in an experiment. Each subject was randomly assigned to cither a treatment group or at control group. Women in the treatment group were intentionally prayed for by several people (called intercessors) who did not know them, a process known as intercessory prayer. 'The praying continued for three weeks following VT. The intercessors did not pray for the women in the control group. Here are the results: 44of the 88women in the treatment group got pregnant, compared to 21out of 81in the control group.

Is the pregnancy rate significantly higher for women who received intercessory prayer? To find out, researchers perform a test of H0:P1=P2versus H伪:P1>P2, where P1&P2are the actual pregnancy rates for women like those in the study who do and don't receive intercessory prayer, respectively,

(a) Name the appropriate test and check that the conditions for carrying out this test are met.

(b) The appropriate test from part (a) yields a P-value of 0.0007. Interpret this P-value in context.

(c) What conclusion should researchers draw at the 伪=0.05significance level? Explain.

(d) The women in the study did not know if they were being prayed for. Explain why this is important.

A fast-food restaurant uses an automated filling machine to pour its soft drinks. The machine has different settings for small, medium, and large drink cups. According to the machine鈥檚 manufacturer, when the large setting is chosen, the amount of liquid dispensed by the machine follows a Normal distribution with mean 27ounces and standard deviation0.8ounces. When the medium setting is chosen, the amount of liquid dispensed follows a Normal distribution with mean 17ounces and standard deviation 0.5ounces. To test the manufacturer鈥檚 claim, the restaurant manager measures the amount of liquid in a random sample of 25cups filled with the medium setting and a separate random sample of 20cups filled with the large setting. Let x炉1-x炉2be the difference in the sample mean amount of liquid under the two settings (large 鈥� medium). Find the mean and standard deviation of the sampling distribution.
See all solutions

Recommended explanations on Math Textbooks

Discrete Mathematics

Read Explanation

Decision Maths

Read Explanation

Theoretical and Mathematical Physics

Read Explanation

Applied Mathematics

Read Explanation

Statistics

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.