/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 34 Gender gap Candidates for politi... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Gender gap Candidates for political office realize that different levels of support among men and women may be a crucial factor in determining the outcome of an election. One candidate finds that \(52 \%\) of 473 men polled say they will vote for him, but only \(45 \%\) of the 522 women in the poll express support. a) Write a \(95 \%\) confidence interval for the percent of male voters who may vote for this candidate. Interpret your interval. b) Write and interpret a \(95 \%\) confidence interval for the percent of female voters who may vote for him. c) Do the intervals for males and females overlap? What do you think this means about the gender gap? d) Find a \(95 \%\) confidence interval for the difference in the proportions of males and females who will vote for this candidate. Interpret your interval. e) Does this interval contain zero? What does that mean? f) Why do the results in parts c and e seem contradictory? If we want to see if there is a gender gap among voters with respect to this candidate, which is the correct approach? Why?

Short Answer

Expert verified
The gender gap is significant since the interval for difference does not include zero. This means there's a true difference in support between genders.

Step by step solution

01

Determine Proportion Estimates

Calculate the proportion estimates for both males and females. For males, the proportion supporting the candidate is \( \hat{p}_{m} = \frac{0.52 \times 473}{473} = 0.52 \). For females, it is \( \hat{p}_{f} = \frac{0.45 \times 522}{522} = 0.45 \).
02

Confidence Interval for Males

To calculate the 95% confidence interval for the proportion of male voters, use the formula: \( \hat{p} \pm z \times \sqrt{\frac{\hat{p}(1-\hat{p})}{n}} \). For males, \( \hat{p}_{m} = 0.52 \), \( n = 473 \), and \( z = 1.96 \) for a 95% confidence level. Thus, the interval is:\[ 0.52 \pm 1.96 \times \sqrt{\frac{0.52 \times 0.48}{473}} \approx 0.52 \pm 0.045 \].
03

Interpretation for Males

The 95% confidence interval for male voters is approximately (47.5%, 56.5%). This means we are 95% confident that the true proportion of male voters who support the candidate lies between 47.5% and 56.5%.
04

Confidence Interval for Females

Repeat the calculation for females with \( \hat{p}_{f} = 0.45 \), \( n = 522 \). The interval becomes:\[ 0.45 \pm 1.96 \times \sqrt{\frac{0.45 \times 0.55}{522}} \approx 0.45 \pm 0.043 \].
05

Interpretation for Females

The 95% confidence interval for female voters is approximately (40.7%, 49.3%). This means we are 95% confident that the true proportion of female voters who support the candidate lies between 40.7% and 49.3%.
06

Check for Overlap Between Intervals

Compare the two confidence intervals: (47.5%, 56.5%) for males and (40.7%, 49.3%) for females. These intervals overlap, suggesting that the proportions of male and female supporters are not definitively different.
07

Difference in Proportions

Calculate the 95% confidence interval for the difference in proportions \( \hat{p}_{m} - \hat{p}_{f} = 0.52 - 0.45 = 0.07 \). The standard error is:\[ SE = \sqrt{\frac{0.52 \times 0.48}{473} + \frac{0.45 \times 0.55}{522}} \approx 0.030 \].The interval is:\[ 0.07 \pm 1.96 \times 0.030 \approx 0.07 \pm 0.058 \].
08

Interpretation of Difference

The confidence interval for the difference in proportion is approximately (0.012, 0.128). We are 95% confident that the true difference in proportions between male and female supporters is between 1.2% and 12.8%.
09

Does the Interval Contain Zero?

The interval (0.012, 0.128) does not contain zero, indicating there is a statistically significant difference between male and female support.
10

Contradiction Exploration

Although individual intervals overlap, the interval for the difference in proportions does not include zero, highlighting a genuine gender gap. The difference approach is more reliable for identifying gaps, as it assesses overall disparity rather than individual segment overlaps.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Gender Gap Analysis
Gender Gap Analysis is an important approach when analyzing voter behaviour, as it helps to identify differences in political preferences between genders. In this particular exercise, there is a focus on measuring how much support a political candidate receives from male versus female voters.

The concept stems from a real-world expectation that gender influences decision-making processes, reflected in the potential voting patterns. The percentages of men and women supporting the candidate are calculated to observe if a noticeable gap exists. With men showing 52% support and women showing 45% support, initial observations suggest there might be a gender gap. To draw meaningful conclusions, we perform further statistical analysis like building confidence intervals around these proportions to understand the variability and confidence in these estimates. These analyses help politicians strategize their campaigns by highlighting target areas needing more focus or a different approach.

Hence, Gender Gap Analysis provides a structured way to uncover such voter discrepancies that could sway election outcomes. It becomes essential when devising strategies to bridge these gaps or to capitalize on them for political gain.
Proportion Estimates
Proportion Estimates are used to represent the level of support from various groups in the population. For this exercise, the proportion estimate for each gender is calculated by determining the fraction of the respondents who express support for the candidate.

For instance, in our example, 52% of men and 45% of women support the candidate, based on the total number of respondents in each category. The formula used is fairly straightforward:
  • For men: \( \hat{p}_{m} = \frac{0.52 \times 473}{473} = 0.52 \)
  • For women: \( \hat{p}_{f} = \frac{0.45 \times 522}{522} = 0.45 \)
These proportions are crucial because they provide essential summary statistics that describe voters' preferences, allowing us to run further analyses, such as constructing confidence intervals.

Understanding and calculating these proportions is the foundational step in the whole statistical analysis process. It allows us to standardize comparisons between different groups, which is critical when evaluating the potential outcome of an election.
Confidence Interval Interpretation
Confidence Interval Interpretation is a vital concept in understanding how certain we are about the population parameters, based on a sample. A confidence interval gives a range that likely includes the true population parameter with a specified level of confidence.

For the male voters, we calculated a 95% confidence interval of (47.5%, 56.5%) for the proportion who may support the candidate. This range means we can be 95% confident that the true proportion of all male supporters falls within this interval. Similarly, for female voters, the interval is (40.7%, 49.3%), indicating with 95% confidence where the true proportion lies.

The overlapping intervals might initially seem contradictory, but they showcase the statistical uncertainty in our estimates. It suggests that while each gender's estimated support range may not distinctly separate, the relatively wider range for women implies potential variability in support predictions.

Thus, understanding these intervals is crucial for interpreting the certainty of statistical estimates, particularly in a politically sensitive analysis like voting tendencies.
Difference in Proportions
The Difference in Proportions analysis seeks to evaluate whether there is a real disparity in support between two groups—in this case, male and female voters.

In the given scenario, the difference in their support appears to be 7% (0.52 - 0.45). To more accurately capture this, we compute a 95% confidence interval for this difference using the standard error of proportions:
  • Standard error \( SE \approx 0.030 \)
  • Confidence interval for difference: \( 0.07 \pm 1.96 \times 0.030 \)
This interval is approximately (1.2%, 12.8%). Notably, this interval does not include zero, indicating that there is a statistically significant difference in support between male and female voters.

Therefore, this method provides a more concrete evidence of a gender gap, reinforcing the need to look at differences collectively rather than focusing merely on overlapping individual proportions. This approach highlights clearer insights into the political landscape and helps strategize campaign efforts more efficiently.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Mammograms A 9 -year study in Sweden compared 21,088 women who had mammograms with 21,195 who did not. Of the women who underwent screening, 63 died of breast cancer, compared to 66 deaths among the control group. (The New York Times, Dec 9, 2001) a) Do these results support the effectiveness of regular mammograms in preventing deaths from breast cancer? b) If your conclusion is incorrect, what kind of error have you committed?

Revealing information 886 randomly sampled teens were asked which of several personal items of information they thought it okay to share with someone they had just met. \(44 \%\) said it was okay to share their e-mail addresses, but only \(29 \%\) said they would give out their cell phone numbers. A researcher claims that a twoproportion \(z\) -test could tell whether there was a real difference among all teens. Explain why that test would not be appropriate for these data.

Pain Researchers comparing the effectiveness of two pain medications randomly selected a group of patients who had been complaining of a certain kind of joint pain. They randomly divided these people into two groups, then administered the pain killers. Of the 112 people in the group who received medication \(A, 84\) said this pain reliever was effective. Of the 108 people in the other group, 66 reported that pain reliever \(B\) was effective. a) Write a \(95 \%\) confidence interval for the percent of people who may get relief from this kind of joint pain by using medication A. Interpret your interval. b) Write a \(95 \%\) confidence interval for the percent of people who may get relief by using medication B. Interpret your interval. c) Do the intervals for \(A\) and \(B\) overlap? What do you think this means about the comparative effectiveness of these medications? d) Find a \(95 \%\) confidence interval for the difference in the proportions of people who may find these medications effective. Interpret your interval. e) Does this interval contain zero? What does that mean? f) Why do the results in parts c and e seem contradictory? If we want to compare the effectiveness of these two pain relievers, which is the correct approach? Why?

Origins In a 1993 Gallup poll, \(47 \%\) of the respondents agreed with the statement "God created human beings pretty much in their present form at one time within the last 10,000 years or so." When Gallup asked the same question in \(2008,\) only \(44 \%\) of those respondents agreed. Is it reasonable to conclude that there was a change in public opinion given that the P-value is 0.17? Explain.

\- Online activity checks Are more parents checking up on their teen's online activities? A Pew survey in 2004 found that \(33 \%\) of 868 randomly sampled teens said that their parents checked to see what Web sites they visited. In 2006 the same question posed to 811 teens found \(41 \%\) reporting such checks. Do these results provide evidence that more parents are checking?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.