Fundamentals of Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (5th Edition)

5th Edition

ISBN: 9780134763699

Author: Michael Sullivan III

Publisher: PEARSON

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2-Proportion Test

In a 2-proportion test, two separate proportions are measured at the same time, and their similarity is evaluated. It is also known as a 2-proportion z-test, and a comparison of two different proportions is done in this method.

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Textbook Question

Chapter 11.3, Problem 23AYU

Putting It Together: Online Homework Professor Stephen Zuro of Joliet Junior College wanted to determine whether an online homework system (meaning students did homework online and received instant feedback with helpful guidance about their answers) improved scores on a final exam. In the fall semester, he taught a precalculus class using an online homework system. In the spring semester, he taught a precalculus class without the homework system (which meant students were responsible for doing their homework the old-fashioned way—paper and pencil). Professor Zuro made sure to teach the two courses identically (same text, syllabus, tests, meeting time, meeting location, and so on). The table summarizes the results of the two classes on their final exam.

	Fall Semester	Spring Semester
Number of students	27	25
Mean final exam score	73.6	67.9
Standard deviation final exam score	10.3	12.4

a. What type of experimental design is this?
b. What is the response variable? What are the treatments in the study?
c. What factors arc controlled in the experiment?
d. In many experiments, the researcher will recruit volunteers and randomly assign the individuals to a treatment group. In what regard was this done for this experiment?
e. Did the students perform better on the final exam in the fall semester? Use an α = 0.05 level of significance.
f. Can you think of any factors that may confound the results? Could Professor Zuro have done anything about these confounding factors?

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Chapter 11.3, Problem 22AYU

Chapter 11.3, Problem 24AYU

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Chapter 11 Solutions

Fundamentals of Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (5th Edition)

Ch. 11.1 - A sampling method is _____ when the individuals...Ch. 11.1 - A sampling method is _____ when the individuals...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - In Problems 38, determine whether the sampling is...Ch. 11.1 - Prob. 8AYU Ch. 11.1 - In Problems 912, conduct each test at the = 0.05...Ch. 11.1 - In Problems 912, conduct each test at the = 0.05...

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Solution Summary: The author explains that the type of experimental design is completely randomized. The response variable is scores on the final exam and the treatments are online homework system versus old-fashioned paper-and-pencil home work.

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