Open source textbook. A professor using an open source introductory statistics book predicts that 60% of the students will purchase a hard copy of the book, 25% will print it out from the web, and 15% will read it online. At the end of the semester he asks his students to complete a survey where they indicate what format of the book they used. Of the 126 students, 71 said they bought a hard copy of the book, 30 said they printed it out from the web, and 25 said they read it online.
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State the hypotheses for testing if the professor’s predictions were inaccurate.
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How many students did the professor expect to buy the book, print the book, and read the book exclusively online?
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This is an appropriate setting for a chi-square test. List the conditions required for a test and verify they are satisfied.
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Calculate the chi-squared statistic, the degrees of freedom associated with it, and the p-value.
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Based on the p-value calculated in part (d), what is the conclusion of the hypothesis test? Interpret your conclusion in this context.