38. Junk mail Direct mail advertisers send solicitations (a.k.a. "junk mail") to thousands of potential customers in the hope that some will buy the company's product. The acceptance rate is usually quite low. Suppose a company wants to test the response to a new flyer, and sends it to 1000 people randomly selected from their mailing list of over 200,000 people. They get orders from 123 of the recipients. a) Create a 90% confidence interval for the percentage of people the company contacts who may buy something. b) Explain what this interval means. c) Explain what "90% confidence" means.

38. Junk mail Direct mail advertisers send solicitations (a.k.a. "junk mail") to thousands of potential customers in the hope that some will buy the company's product. The acceptance rate is usually quite low. Suppose a company wants to test the response to a new flyer, and sends it to 1000 people randomly selected from their mailing list of over 200,000 people. They get orders from 123 of the recipients. a) Create a 90% confidence interval for the percentage of people the company contacts who may buy something. b) Explain what this interval means. c) Explain what "90% confidence" means.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

A kilo restaurant implemented a change in the composition and presentation of its dishes. We want to assess whether the average weight of meals served is greater after the changes, compared to the previous average, which was 640. For this purpose, the weights of dishes from a random sample of 10 customers were taken. The average weight of dishes in the sample was 656 and the variance 144. Use a statistical test for the evaluation. Adopt a significance level of 10%. a. What is the value of the test statistic? b. What range of values is the p-value in? c. At the 10% significance level, can you reject the null hypothesis?
Michael wants to know if support for a local referendum on gay rights is related to political party affiliation. He conducts a survey of 200 local residents and asks them their political party affiliation and whether they intend to vote for or against the referendum. He learns that 16 people who say they are republican are for the referendum and 54 are against. Of those who say they are democrat, 72 people are for the referendum and 28 are against it. Some people identified as “other” and among that group, 3 were against the referendum and 27 were in favor of it. 1. Conduct the appropriate analysis with α=.05. 2. What should Michael conclude?
6) A small business owner you follow on TikTok is SO EXCITED because last month, she was able to begin selling her product in a popular chain store around the nation. Her contract with the chain store says that at any time, there will be at least 20 of her products sitting out on the shelves. She wants to conduct a survey to see if that is true. She visits 5 of the local chain stores around her and records the number of products of hers that are on the shelves. She will then construct a 95% confidence interval to determine the mean number of products on the shelves for all of the stores. (a) Discuss whether this study meets the each of the conditions for constructing a confidence interval. If one of the conditions has not been met, what additional information would be required or what change in the study would you recommend? (b) If, instead of constructing a 95% confidence interval, the business owner constructed a 98% confidence interval, would the 98% interval be wider, narrower, or…
A poll was taken of 100 students at a commuter campus to find out how they got to campus. The results were as follows: 31 said they drove alone. 32 rode in a carpool. 28 rode public transportation. 4 used both carpools and public transportation. 5 used both a carpool and sometimes their own cars. 3 used buses as well as their own cars. 1 used all three methods. How many used none of the above-mentioned means of transportation?students
2. In how many ways can five students queue for tickets for a show?
) A recent poll surveyed 1587 adults (18 years of age and older, residing in the contiguous United States, contacted by phone from randomly selected homes). Residents who agreed to participate were categorized according to their political party preference (Democrat, Republican or other) and their gender (male or female). To make life easier, we’ll focus on the responses from the south (37% of the sample or 588 people). Our question is about the “Gender Gap” in American politics (the gender gap is described as differences in voting preferences for men and women). Is voting preference independent of gender? What test should you use and why?
3. A poll done for Newsweek found that 10% of Americans have seen or sensed the presence of an angel. A contingent doubt that the percent is really that high. It conducts its own survey. Out of 85 Americans surveyed, only 5 had seen or sensed the presence of an angel. As a result of the contingent's survey, would you agree with the Newsweek poll? In complete sentences, also give three reasons why the two polls might give different results.
4. A company’s CEO has 8 people reporting directly to her, and she wantsto select 2 to attend the grand opening of a new retail store. How many possible ways are there of selecting 2 people to attend?
A report in the college newsletter used the registrar's database for all the students in the school to look at majors and classes being taken this semester. The report includes the sentences:
B7
2. A survey on a sample of 35 new cars being sold at a local auto dealer was conducted to see which of three popular options: Air-conditioning (A), Bluetooth (B), and Rear Camera (C), were already installed. The survey found: 18 had A, 13 had B, 12 had C, 5 had A and B, 8 had A and C, 6 had B and C, 4 had all three options. Find the number of cars that had (a) A and B but not C, (b) A and C but not B, (c) B and C but not A; (d) only one of the options; (e) at least one option; (f) exactly two options; (g) none of the options.