Intro Stats
4th Edition
ISBN: 9780321826275
Author: Richard D. De Veaux
Publisher: PEARSON
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Chapter 11, Problem 39E
Omega-3, finis Exercises 21, 35, and 37 describe an experiment investigating the effectiveness of omega-3 fats in treating bipolar disorder. Suppose some of the 30 subjects were very active people who walked a lot or got vigorous exercise several times a week, while others tended to be more sedentary, working office jobs and watching a lot of TV. Why might researchers choose to block the subjects by activity level before randomly assigning them to the omega-3 and placebo groups?
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Students have asked these similar questions
One hundred students were surveyed about their preference between dogs and cats. The following two-way table displays data for the sample of students who responded to the survey.
Preference
Male
Female
TOTAL
Prefers dogs
\[36\]
\[20\]
\[56\]
Prefers cats
\[10\]
\[26\]
\[36\]
No preference
\[2\]
\[6\]
\[8\]
TOTAL
\[48\]
\[52\]
\[100\]
problem 1
Find the probability that a randomly selected student prefers dogs.Enter your answer as a fraction or decimal.
\[P\left(\text{prefers dogs}\right)=\]
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Preference
Male
Female
TOTAL
Prefers dogs
\[\blueD{36}\]
\[\blueD{20}\]
\[\blueE{56}\]
Prefers cats
\[10\]
\[26\]
\[36\]
No preference
\[2\]
\[6\]
\[8\]
TOTAL
\[48\]
\[52\]
\[100\]
There were \[\blueE{56}\] students in the sample who preferred dogs out of \[100\] total students.
Business discuss
You have been hired as an intern to run analyses on the data and report the results back to Sarah; the five questions that Sarah needs you to address are given below.
Does there appear to be a positive or negative relationship between price and screen size? Use a scatter plot to examine the relationship.
Determine and interpret the correlation coefficient between the two variables. In your interpretation, discuss the direction of the relationship (positive, negative, or zero relationship). Also discuss the strength of the relationship.
Estimate the relationship between screen size and price using a simple linear regression model and interpret the estimated coefficients. (In your interpretation, tell the dollar amount by which price will change for each unit of increase in screen size).
Include the manufacturer dummy variable (Samsung=1, 0 otherwise) and estimate the relationship between screen size, price and manufacturer dummy as a multiple linear regression model.
Interpret the…
Chapter 11 Solutions
Intro Stats
Ch. 11.3 - At one time, a method called gastric freezing was...Ch. 11.4 - Recall the experiment about gastric freezing, an...Ch. 11 - Steroids The 1990s and early 2000s could be...Ch. 11 - Prob. 2ECh. 11 - Prob. 3ECh. 11 - Tomatoes You want to compare the tastiness and...Ch. 11 - Tips II For the experiment described in Exercise...Ch. 11 - Prob. 6ECh. 11 - Prob. 7ECh. 11 - Prob. 8E
Ch. 11 - Prob. 9ECh. 11 - Prob. 10ECh. 11 - Block that tip The driver of Exercise 3 wants to...Ch. 11 - Blocking tomatoes To obtain enough plants for the...Ch. 11 - Prob. 13ECh. 11 - Prob. 14ECh. 11 - Standardized test scores For his statistics class...Ch. 11 - Heart attacks and height Researchers who examined...Ch. 11 - Prob. 17ECh. 11 - Prob. 18ECh. 11 - Menopause Researchers studied the herb black...Ch. 11 - Honesty Coffee stations in offices often just ask...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - 2134. Whats the design? Read each brief report of...Ch. 11 - Omega-3 Exercise 21 describes an experiment that...Ch. 11 - Insomnia Exercise 24 describes an experiment...Ch. 11 - Omega-3, revisited Exercises 21 and 35 describe an...Ch. 11 - Insomnia, again Exercises 24 and 36 describe an...Ch. 11 - Omega-3, finis Exercises 21, 35, and 37 describe...Ch. 11 - Insomnia, at last Exercises 24, 36, and 38...Ch. 11 - Injuries Exercise 33 describes an experiment that...Ch. 11 - Tomatoes II Describe a strategy to randomly split...Ch. 11 - Shoes A running-shoe manufacturer wants to test...Ch. 11 - Swimsuits A swimsuit manufacturer wants to test...Ch. 11 - Hamstrings Exercise 33 discussed an experiment to...Ch. 11 - Diet and blood pressure An experiment showed that...Ch. 11 - Mozart Will listening to a Mozart piano sonata...Ch. 11 - Contrast baths Contrast bath treatments use the...Ch. 11 - Prob. 49ECh. 11 - Swimming Recently, a group of adults who swim...Ch. 11 - Dowsing Before drilling for water, many rural...Ch. 11 - Healing A medical researcher suspects that giving...Ch. 11 - Reading Some schools teach reading using phonics...Ch. 11 - Gas mileage Do cars get better gas mileage with...Ch. 11 - Weekend deaths A study published in the New...Ch. 11 - Shingles A research doctor has discovered a new...Ch. 11 - Beetles Hoping to learn how to control crop damage...Ch. 11 - SAT prep Can special study courses actually help...Ch. 11 - Safety switch An industrial machine requires an...Ch. 11 - Washing clothes A consumer group wants to test the...Ch. 11 - Skydiving, anyone? A humor piece published in the...
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