Mathematics Homework Help

Howard Community College Confidence Intervals for Sample Proportions Report

 

Background: For this assignment, you will use a StatCrunch file containing the survey results dating back to 2004 for two questions from the GPSS. The first asks, “In politics, as of today, do you consider yourself a Republican, a Democrat or an independent?” If a respondent identifies as independent, a follow-up question is asked, “As of today, do you lean more to the Democratic Party or the Republican Party?” The data in the last two columns of the file contain the combined figures of party identifiers and leaners. Each Gallup survey that is part of this series requires at least 1000 respondents. For the purpose of this assignment, we will assume that every survey had exactly 1000 respondents. To access the StatCrunch file, follow this link:  Party Affiliation Data (Links to an external site.)

Assignment/Instructions:

STEP 1: Ask a question involving the change in party affiliation for one party between two dates.

For example, I could ask, “Has the proportion of adults nationwide who identify as democrat changed from June 2019 to June 2020?”

STEP 2: Look up the two proportions corresponding to your question in the StatCrunch data file and report them in your document.

For my example, I will say, “According to the Gallup Poll given in June 2019, 29% of adults identified themselves as democrat and in June 2020, 33% of adults identified themselves as democrat.” 

STEP 3: Use StatCrunch to find a 95% confidence interval for each proportion using n = 1000 and copy the results into your document.

For my example, I would use ?ˆ=0.29p^=0.29 and n = 1000 to find the first confidence interval, and ?ˆ=0.33p^=0.33 and n = 1000 to find the second confidence interval. 

STEP 4: Interpret each confidence interval that you found in Step 3 and answer your question using what you know about confidence intervals.