Confidence interval for the proportion of individuals

Assignment Help Basic Statistics
Reference no: EM13915854

A consumer products firm has recently introduced a new brand. The firm would like to estimate the proportion of people in its target market segment who are aware of the new brand. As part of a larger market research study, it was found that in a sample of 125 randomly selected individuals from the target market segment, 84 individuals were aware of the firm's new brand.

a) Construct a 95% confidence interval for the proportion of individuals in the target market segment who are aware of the firm's new brand. If you use Excel and/or StatTools, please specify any functions you use and all the inputs.

b) The manager in charge of the new brand has stated that the brand awareness is greater than .75, meaning that more than 75% of the population is aware of the brand. He would like to use hypothesis testing to prove his claim. At the 5% significance level, conduct a hypothesis test with the goal of proving his claim. In particular

i) specify the null hypothesis and the alternative hypothesis,
ii) state whether you are using a one- or two-tailed test,
iii) specify the p-value of the test, and
iv) provide the results of the test in "plain English".

Hints:

1) Think carefully about what is the null hypothesis, and what is the alternative.

2) If you want to use StatTools for the analysis, you need to create the survey data in Excel first; then you can run the analysis.

For future polls, the firm is interested in minimizing their marketing-research costs. The margin of error (MOE) in their pools should be no larger than B (i.e., ± 100B percentage points). To simplify the analysis, we will assume their marketing study only has a single question that is used to estimate p, at the 5% significance level.

a. If the firm had no prior knowledge of p, how large would the sample size have to be to ensure MOE ≤ B? (Hint: your answer will be a formula containing B).

b. The firm has prior knowledge that p will likely be somewhere between .10 and .20 (that is between 10% and 20%). How large should the sample be if they would like to ensure that MOE (=B) is no larger than 0.01 or 1%?

Reference no: EM13915854

Questions Cloud

Problem regarding the website migration project : Tony's Chips has recently been sold to a new independent company. The new company has hired you to manage a project that will move the old Website from an externally hosted solution to an internal one.
Identify two sites with sample business proposals : Identify two sites with sample business proposals. Outline the parts of each proposal. Compare the strengths and weaknesses of each proposal.
Statistical releases of data : Make sure to select articles (300 words or more) that address all of the needed information below. Short articles will often not provide you with enough detail to write about. In addition, purely statistical releases of data are not wise selection..
Develop a letter proposal outlining your plan and staffing : As a team, develop a letter proposal outlining your plan, staffing, and budget. Use persuasion to show why contracting your services is better than hiring in-house employees.
Confidence interval for the proportion of individuals : Construct a 95% confidence interval for the proportion of individuals in the target market segment who are aware of the firm's new brand. If you use Excel and/or StatTools, please specify any functions you use and all the inputs.
Cost of goods sold : What is cost of goods sold?
Concentration of carbon dioxide : An increase in the concentration of carbon dioxide in the atmosphere is contributing to
Short-term or long-term unemployment : Are the following workers more likely to experience short-term or long-term unemployment? Explain.
Final answers to nearest dollar or whole number : The company did not maintain any inventories, so total cost of goods sold was $4,400. Selling expenses totalled $1,600 ($600 variable and $1,000 fixed), and administrative expenses totaled $1,500 ($500 variable and $1,000 fixed). Operating income was..

Reviews

Write a Review

Basic Statistics Questions & Answers

  What is the probability that the company makes a profit

Assuming that both turnover and costs have normal distributions, each with a standard deviation of $250000, what is the probability that the company makes a profit?

  Total standard deviation in data

Given that standard deviation process=4.7 and standard deviation gage=3.4, what is the total standard deviation in data from this process?

  Upper bound or limit of confidence interval

The superintendent of a unified school district of a small town wants to make sure that no more than 5% of the students skip more than 10 days of school in a year.

  Mean score and standard deviation

In the history class the mean score was 76 with standard deviation 3.

  Population standard deviations-margin of error

The average age of the women was 36.97 with a standard deviation of 8.893. If a 95% confidence interval is calculated to estimate the difference between the two average ages, what is the margin of error? Assume both population standard deviations ..

  Estimating-population mean difference

Make a point estimate of the population mean difference in endurance after taking the herbs. Make a 95% confidence interval estimate of the population mean difference.

  If 70 percent of the population of a large community is in

if 70 percent of the population of a large community is in favor of a proposed rise in school taxes using the normal

  The campus security leaders believe that the total crime

what crimes were most commonly committed on minnesota campuses between 2009 and 2011?based on the data would you say

  Determine and interpret p-value for testing mean weight

Population standard deviation is known to be 8 grams. Determine and interpret p-value for testing that mean weight of Take-a-Bite is less than 175 grams.

  Problem 1 - what sample size is needed to obtain a 90

problem 1 - what sample size is needed to obtain a 90 percent confidence interval for the mean protein content of meat

  What is the probability that at least one of the three

use the following information to answer the question. suppose that a recent poll of american households about pet

  Correlation coefficient testing and r-square value

Determine the proportion of variation in grade that can be explained by the linear correlation between the grade and the number of credit hours earned at the same time of taking the course.

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd