Part 1)
In this assignment, you will use the StatCrunch U data set that you developed (the one you have done before)
As you did in StatCrunchAssignment look at the items in the StatCrunch U survey and develop a question regarding population proportions that can be answered using the survey data you collected.
As a reminder, here are the items on the survey:
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Here are some possible questions. Feel free to pick one of those questions-but it would be better for you to formulate a question of your own. For this assignment, you need a question related to proportions and one that will require the use of a confidence interval and hypothesis test to answer.
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Is the proportion of seniors less than the proportion of freshman?
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Is the proportion of male students who work different from the proportion of female students who work?
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Is the proportion of students with student loans who work greater than the proportion of students without student loans who work?
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Is the proportion of female students with credit card debt greater than the proportion of male students with credit card debt?
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Is the proportion of male freshman students different from the proportion of male senior students?
Answer each of the following questions. Point values are indicated with each question.
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State your question. Remember that your question should be related to the population proportion or proportions and should be one that will require the use of a confidence interval and hypothesis test to answer. Assume that your sample is representative of the population.
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Explain the methodology you will use to answer the question you posed. Your explanation should include answers to the following questions. Do not include your analysis or answers to your question here-only describe how you will do the analysis.
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Carry out the methodology described in 2 above. Use StatCrunch and paste copies of the StatCrunch output in the space below. (NOTE: For the purposes of this assignment, go ahead and complete the confidence interval and hypothesis test even if there are not at least 10 successes and 10 failures.) Your explanation should include answers to the following questions:
Hypothesis test results:
p1 : Proportion of successes (Success = true) for Loan where Gender = Male
p2 : Proportion of successes (Success = true) for Loan where Gender = Female
p1 - p2 : Difference in proportions
H0 : p1 - p2 = 0
HA : p1 - p2 ≠ 0
Difference
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Count1
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Total1
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Count2
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Total2
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Sample Diff.
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Std. Err.
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Z-Stat
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P-value
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p1 - p2
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4
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12
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9
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18
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-0.16666667
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0.18467522
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-0.90248526
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0.3668
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95% confidence interval results:
p1 : Proportion of successes (Success = true) for Loan where Gender = Male
p2 : Proportion of successes (Success = true) for Loan where Gender = Female
p1 - p2 : Difference in proportions
Difference
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Count1
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Total1
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Count2
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Total2
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Sample Diff.
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Std. Err.
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L. Limit
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U. Limit
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p1 - p2
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4
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12
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9
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18
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-0.16666667
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0.18002057
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-0.51950051
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0.18616718
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Based on the results of 2 and 3 above, answer your question. Include an explanation of how you used the StatCrunch output to formulate your answer.
Part 2)
Go to a website for a company or agency that does polling, find the results of a poll they've done recently, and give a brief summary of the results. You can copy from their website as long as you tell where you got the info. Possible polling agencies are Gallup, Rasmussen, Zogby, RealClearPolitics, national news organizations, and others.
After posting the summary of the poll from the website, copy and answer the following questions/items using the summary you found. (complete explanation)
1)State the confidence interval it two ways:
a. The lower to upper limits.
b. As the sample proportion +/- the error term.
2)What was the sample size and how was the data collected?
3)State the meaning of the confidence interval in terms of the specific question or poll.