/*! 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 19 Radio and television stations of... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Radio and television stations often air controversial issues during broadcast time and ask viewers to indicate their agreement or disagreement with a given stand on the issue. A poll is conducted by asking those viewers who agree to call a certain 900 telephone number and those who disagree to call a second 900 telephone number. All respondents pay a fee for their calls. a. Does this polling technique result in a random sample? b. What can be said about the validity of the results of such a survey? Do you need to worry about a margin of error in this case?

Short Answer

Expert verified
Explain the validity of the results and whether margin of error should be a concern in this case. Answer: No, the polling technique used by radio and television stations does not result in a random sample. This is because only those viewers who feel strongly about the issue and are willing to pay the call fee will participate, creating a self-selection bias. As a result, the validity of the survey results can be questionable and may not accurately represent the opinions of the entire population. In this case, focusing on identifying the potential biases and sources of unreliability is more beneficial than calculating the margin of error.

Step by step solution

01

a. Does this polling technique result in a random sample?

This polling technique does not result in a random sample. The main reason is that the respondents are self-selected, meaning that only those viewers who feel strongly about the issue and are willing to pay the call fee will participate in the poll. This self-selection bias can lead to an unrepresentative sample of the entire population, as it is likely that those who don't care about the issue or don't want to pay the fee will not participate.
02

b. Validity of the results and margin of error

Due to the self-selection bias mentioned earlier, the validity of the survey results can be questionable. The survey may not accurately represent the opinions of the entire population because it only includes the opinions of people who are motivated and willing to pay the fee to express their views. As for the margin of error, it is usually calculated based on the sample size and the response distribution in a random sample. However, since this polling technique does not result in a random sample, it may not be appropriate to calculate the margin of error for this survey. Instead, it would be more beneficial to focus on identifying the potential biases and sources of unreliability in the survey.

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!

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

At a time in U.S. history when there appears to be genuine concern about the number of illegal aliens living in the United States, there also appears to be concern over the number of legal immigrants allowed to move to the United States. In a recent poll that included questions about both legal and illegal immigrants to the United States, \(51 \%\) of the \(n=900\) registered voters interviewed indicated that the U.S. should decrease the number of legal immigrants entering the United States. \(^{3}\) a. What is a point estimate for the proportion of U.S. registered voters who feel that the United States should decrease the number of legal immigrants entering the United States? Calculate the margin of error. b. The poll reports a margin of error of \(\pm 3 \%\). How was the reported margin of error calculated so that it can be applied to all of the questions in the survey?

In developing a standard for assessing the teaching of precollege sciences in the United States, an experiment was conducted to evaluate a teacher-developed curriculum, "Biology: A Community Context" (BACC) that was standards-based, activity-oriented, and inquiry-centered. This approach was compared to the historical presentation through lecture, vocabulary, and memorized facts. Students were tested on biology concepts that featured biological knowledge and process skills in the traditional sense. The perhaps not-so-startling results from a test on biology concepts, published in The American Biology Teacher, are shown in the following table. \({ }^{11}\) $$\begin{array}{lccc} & & \text { Sample } & \text { Standard } \\\& \text { Mean } & \text { Size } & \text { Deviation } \\\\\hline \text { Pretest: All BACC Classes } & 13.38 & 372 & 5.59 \\\\\text { Pretest: All Traditional } & 14.06 & 368 & 5.45 \\\\\text { Posttest: All BACC Classes } & 18.5 & 365 & 8.03 \\\\\text { Posttest: All Traditional } & 16.5 & 298 & 6.96\end{array}$$ a. Find a \(95 \%\) confidence interval for the mean score for the posttest for all BACC classes. b. Find a \(95 \%\) confidence interval for the mean score for the posttest for all traditional classes. c. Find a \(95 \%\) confidence interval for the difference in mean scores for the posttest BACC classes and the posttest traditional classes. d. Does the confidence interval in c provide evidence that there is a real difference in the posttest BACC and traditional class scores? Explain.

Find a \(99 \%\) lower confidence bound for the binomial proportion \(p\) when a random sample of \(n=400\) trials produced \(x=196\) successes.

Suppose you wish to estimate a population mean based on a random sample of \(n\) observations, and prior experience suggests that \(\sigma=12.7\). If you wish to estimate \(\mu\) correct to within 1.6 , with probability equal to .95, how many observations should be included in your sample?

Independent random samples of \(n_{1}=n_{2}=n\) observations are to be selected from each of two binomial populations 1 and \(2 .\) If you wish to estimate the difference in the two population proportions correct to within . 05 , with probability equal to .98 , how large should \(n\) be? Assume that you have no prior information on the values of \(p_{1}\) and \(p_{2},\) but you want to make certain that you have an adequate number of observations in the samples.

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.