Amazon.com is one of the largest Internet-based retailers in the world. The company offers a “prime” membership for a fee, which provides certain benefits for members. A recent report states that 46% of U.S. households have an Amazon “prime” membership. Penelope wants to know if this proportion is different for her large hometown. She selects a random sample of 80 households from her hometown and finds that 43 of them have an Amazon “prime” membership.
Find the p-value for this test.
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Is there convincing evidence that the proportion of households in this town differs from the claim in the report?
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Should this be a one or two sided test?
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4.
Conduct a significance test at a significance level of 5% and find the p-value.
What does the p-value mean in this context?
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What is your conclusion?
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Let's suppose that this conclusion above is incorrect. Not because you did anything wrong! Sampling variability resulted in data that led to the wrong conclusion.
What would be the consequences for the town of this error?
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Assuming the water is "safe" (7% of households), what is the probability that this type of error happens?
Hint: Think about the sampling distribution of all possible outcomes from this kind of study (assuming 7% is the mean). What percent of those outcomes would result in the same incorrect conclusion as we got?
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A different citizen conducted their own independent test and found that 9 households out of 100 have unsafe drinking water.
Conduct a significance test at a significance level of 5% and find the p-value.
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9.
What is your conclusion?
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10.
Let's suppose that this conclusion above is incorrect. Not because you did anything wrong! Sampling variability resulted in data that led to the wrong conclusion.
What would be the consequences for the town of this error?
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11.
Which consequence is worse, the one from #6 or #10?
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12.
Section 9-2
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Section 9-2
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Section 9-1
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Section 9-1
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After checking your answers in the back, are there any questions from above that you are still confused about? I'll try to go over questions that many people select below. If I don't go over it in class, I'm happy to talk to you about it during office hours.
The numbers below correspond to the Formative question numbers
