Question

In: Statistics and Probability

3).A political poll estimates that 48% of Democrat voters will vote for Elizabeth Warren in the...

3).A political poll estimates that 48% of Democrat voters will vote for Elizabeth Warren in the presidential primaries. They provide a "margin of error" of 3 percentage points, which leads to a 95% confidence interval of 45% to 51%.


a) Explain what "95% confidence level" means.
b) Why is a confidence interval needed here? What does it tell us that the "48%" does not tell us?
c) Which of the following is the best interpretation of the confidence interval?
i) 95% of the samples had between 45% and 51% of respondents supporting Warren.
ii) There's a 95% chance that between 45% and 51% of those sampled support Warren.
iii) We are 95% confident that between 45% And 51% of all voters support Warren.
iv) We are 95% confident that between 45% and 51% of those sampled support Warren.

Solutions

Expert Solution


Related Solutions

A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic...
A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, test the claim that at least half of all voters prefer the Democrat. State the sample percentage and sample size.
A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic...
A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, test the claim that at least half of all voters prefer the Democrat. State the decision.
A political poll asked potential voters if they felt the economy was going to get worse,...
A political poll asked potential voters if they felt the economy was going to get worse, or better during the next 12 months. The party affiliations of the respondents were also noted. The results are shown in the following table. To test at the 0.01 level to determine if Party Affiliation and Response are dependent, calculate the chi-square test statistic and p-value.
A poll of 1000 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency.
A poll of 1000 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, do the data provide sufficient evidence to conclude that the percentage of voters who prefer the Democrat is less than 50%?
A monthly public policy poll of registered voters is conducted by Harvard’s Center for American Political...
A monthly public policy poll of registered voters is conducted by Harvard’s Center for American Political Studies and the Harris Poll. In response to the question, “Do you think the country is on the right track or is it off on the wrong track?” 889 of 2403 respondents in March and 1041 of 2563 respondents in February said that they thought the country was on the right track. February polling was conducted between February 26th and 28th. March polling was...
A political polling organization has been hired to conduct a poll of likely voters prior to...
A political polling organization has been hired to conduct a poll of likely voters prior to an upcoming election. Each voter is to be interviewed in person. It is known that the costs of interviewing different types of voters vary due to the difference in proportion within the population. The costs to interview males, for example, are $20 per Democrat, $18 per Republican, and $27 per Independent voter. The costs to interview female are $24, $22 and $28 for Democrat,...
A political poll immediately prior to a local election revealed the following result. ​ Female Voters...
A political poll immediately prior to a local election revealed the following result. ​ Female Voters Male voters Vote Democrat 1200 1150 Vote Republican 2100 950 Total     n1 = 3300 n2 = 2100 Use α = .05. Test to determine whether the proportions of female and male voters who intend to vote for the Democrat candidate differ? Report the test statistic and the p-value. Provide a 99% confidence interval for the difference in the proportion of female and male...
M3_A5. A political polling organization has been hired to conduct a poll of likely voters prior...
M3_A5. A political polling organization has been hired to conduct a poll of likely voters prior to an upcoming election. Each voter is to be interviewed in person. It is known that he costs of interviewing different types of voters vary due to the difference in proportion within the population. The costs to interview males, for example, are $20 per Democrat, $18 per Republican, and $27 per Independent voter. The costs to interview female are $24, $22 and $28 for...
3. Political scientists usually conclude that voters dislike negative campaign ads, but we can use game...
3. Political scientists usually conclude that voters dislike negative campaign ads, but we can use game theory to offer an explanation for why they continue to be used. While negative ads are (nauseatingly) commonplace in electoral competition, they are far less frequent in business competition; i.e., it is rare to see company A directly attacking the quality or character of competing company B to the extent that political candidate X attacks political candidate Y. (We might see a company talk...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT