Confidence interval estimation-hypothesis testing

Assignment Help Basic Statistics
Reference no: EM13105145

Confidence Interval Estimation

1. Compute a 90% confidence interval for the population mean, based on the sample 25, 27, 23, 24, 25, 24, and 59. Change the number from 59 to 24 and recalculate the confidence interval. Using the results, describe the effect of an outlier or extreme value on the confidence interval.

Hypothesis Testing

2. The director of admissions at the University of Maryland, University College is concerned about the high cost of textbooks for the students each semester. A sample of 45 students enrolled in the university indicates that X (bar) = $285.4 and s = $42.20.

a. Using the 0.05 level of significance, is there evidence that the population mean is above $300?

b. What is your answer in (a) if s = $90 and the 0.10 level of significance is used?

c. What is your answer in (a) if X (bar) = $310.10 and s = $40.20?

d. Based on the information in part (a), what decision should the director make about the books used for the courses if the goal is to keep the cost below $300?

3. A large hat manufacturer, MICHAELLA HATS, is concerned that the mean weight of their signature Kentucky Derby hat is not greater than 3.5 pounds. It can be assumed that the population standard deviation is .7 pounds based on past experience. A sample of 350 hats is selected and the sample mean is 3.25 pounds. Using a level of significance of .10, is there evidence that the population mean weight of the hats is greater than 3.5 pounds? Fully explain your answer.

Reference no: EM13105145

Questions Cloud

Conduct a swot analysis for the company : Required to prepare a 4-5 page (APA format) research plan to support introducing the product and service for your marketing plan to the U S market. In addition to stating yuor marketing objectives you are required to Conduct a SWOT analysis for th..
Calculate the expectations : Let X denote the number of students that were on the bus carrying this randomly selected student. One of the 4 bus drivers is also randomly selected. Let Y denote the number of students on his bus. Compute the expectations of X and Y.
Probability-confidence interval : Suppose the salary of assembly line workers has Normal distribution with mean of $20,000, and standard deviation of $3,000.
Probability of choosing graduates : A study conducted at a certain college shows that 53% of the school's graduates find a job in their chosen field within a year of graduation. Find the probability that among 7 randomly selected graduates, at least one finds a job in his or her cho..
Confidence interval estimation-hypothesis testing : Compute a 90% confidence interval for the population mean, based on the sample 25, 27, 23, 24, 25, 24, and 59. Change the number from 59 to 24 and recalculate the confidence interval.
Identify the marketing segment for the product : Identify the marketing segment for the product and Explain why this segment was selected. Discuss the target market and explain why these consumers will be targeted
Analyze and estimate creation of us laws : Write 700 to 1,050 word which you analyze and estimate creation of U.S. Laws, taking into consideration common law heritage and U.S. court history.
Illustrate what factors should considered in price settings : Illustrate what factors should be considered in price setting? Which of these factors is most important? Explain why? Explain why is adapting the price of a product important?
Expected collision payment : Use the expected collision payment to determine the collision insurance premium that would enable the company to break even on the policy.

Reviews

Write a Review

Basic Statistics Questions & Answers

  Types of random sampling

A polling company obtains an alphabetical list of names of voters in a precinct. They select every 20th person from the list until a sample of 100 is obtained.

  Correct pair of hypotheses

An independent financial advisor claims an average rate of return, μ, on a particular investment is at least 7%. In testing her claim, the correct pair of hypotheses is:

  Value of z required for rejection

Given the same significance level, a ________ value of  t  will be required to reject the null hypothesis compared to the value of  z  required for rejection.

  Sample variances-pooled variances

One sample has SS = 48 and a second sample has SS = 32. When both samples have n =5, what is each sample variance and computed pooled variance?

  Selecting a crew member at random

If we select a crew member at random, what is the probability the crew member earns:

  Finding z-value according to a normal distribution

Assume that a random variable, x, is distributed according to a normal distribution with mean 12 and standard deviation 2. Find the z-value if:

  Confidence interval for the true average commuting time

You took the standard deviation of 4.5 minutes from a commuting friend and believe that that is the standard deviation for the area. Prepare a 95% confidence interval for the true average commuting time.

  Mean annual salary of the employees of the business

The mean salary of the nine employees of a small business is $52,000 per year. One employee, whose salary was $68,000, was red. Two new employees, who will each be paid a salary of $40,000, are hired. What is the new mean annual salary of the emp..

  Distribution of the breaking strength

A beverage company is trying to ?nd out the distribution of the breaking strength of their glass bottles. Fifty bottles are selected at random and tested for breaking strength, with the following results (in pounds per square inch):

  Anova and nonparametric tests

Based on your experience using ANOVA and Nonparametric tests, what additional information would you recommend to the key decision maker solve the challenges given in a company that provides software solutions to wide range of clients?

  Statistical theory in business decision making

The theory underlying inferential statistics and other theoretical aspects are subjects we do not often consciously think about in our daily activities.

  Information of expected frequency

Determine the expected frequencies for each of the cells in the following contingency tables. For each problem, state how many of the expected values actually had to be computed and how many could be found by subtraction.

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