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Hypothesis Testing

ANOVA Uses and Contingency Table

1. Name an application for the use of ANOVA. This can be in a professional setting, hobby, or something you find on the internet 2. What are some business situations where ANOVA would be more appropriate than a Z or T test? 3. Find an example of the use of a contingency table from the internet. Describe what it was test

To state null and alternative hypothesis of given problems

(See attached file for full problem description with all symbols) 1. A coin-operated drink machine was designed to discharge a mean of ounces of coffee per cup. Suppose that we want to carry out a hypothesis test to see if the true mean discharge differs from . State the null hypothesis and the alternative hypothesis that

Testing a Null Hypothesis at 0.1 Significance

A New England Journal of Medicine study found that a substantial portion of acute hospital care is unnecessary. The physicians who conducted the study reviewed the medical records of 1,132 patients hospitalized at six different locations across the country. Overall, 60% of the admissions were judged to be appropriate, 23% were d

To test if the serum helps to cure the disease

2. Two groups, A and B, consist of 100 people each who have a disease. A serum is given to group A but not to group B (which is called the control group); otherwise, the two groups are treated identically. It is found that in groups A and B, 75 and 65 people respectively, recover from the disease. a. At a significance level of

Hypothesis Testing Review - 2 Questions

An investment services company claims that the average annual return on stocks within a certain industry is 11.5%. An investor wants to test whether this claim is true and collects a random sample of 50 stocks in the industry of interest. He finds that the sample average annual return is 10.8% and that the sample standard deviat

Stat Problem

The mean wage of workers in a certain industry over the whole country is $210 per week, with a standard deviation of $7.50. A sample of 100 workers from one large factory is found to have a mean wage of $208 per week. Are the workers in this factory different from the rest of the industry?

Finding population means

Fairfield homes is developing two parcels near Pigeon Fork, Tenn. In order to test different advertising approaches, they use different media to reach potential buyers. The mean annual family income for 75 people making inquires at the first development is $150,000, with a standard deviation of $40,000. A corresponding sample of

Finding the p-value

The management of discount furniture, a chain of discount furniture stores in the northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12 Salespeople were selected at random, and their weekly incomes before and after the plan were recorded. Sid: before $320, after $340 Carol: before $290

Statistical hypothesis testing of temperature instruments

A company compared the performance of two temperature instruments: one coupled to a process computer and the other used for visual control. Ideally, these two instruments should agree. The following data are the two temperatures over a five day period: (see chart in attached file) a. Conduct the most appropriate hypothesis

Statistical processes

1. The yields from an ethanol-water distillation column have a standard deviation of 0.01. Process specifications call for a target yield of 0.93. Management wishes to detect any decrease in the true mean yield. a. A random sample of 8 recent batches produced the following yields. Conduct a hypothesis test to determine

Hypothesis Testing

Please provide analysis to the attached article 1.) Briefly summarize the article 2.) Identify the hypothesis described in the article 3.) Explain how the hypothesis statement was used in the study

Confidence interval and hypothesis testing

Captopril is a drug designed to lower systolic blood pressure. When subjects were tested with this drug, their systolic blood pressure readings (in mm of mercury) were measured before and after the drug were taken, with the results given in the table: a. Construct a 99% confidence interval for the mean difference between the

Statistical relationship & cross tabulation

Please help set up this problem and create the pivot table in excel. 1. The attached file MBA.XLS contains the results of a study on the academic preparation of MBA students and their performance in a Quantitative Analysis Course. A group of 181 students, constituting a random sample, was classified according to their latest

Formula's for Statistical Problems: Lisa Monnin and Discount Furniture

Exercise # 14 The null and alternate hypotheses are: A random sample of 15 observations from the first population revealed a sample mean of 350 and a sample standard deviation of 12. A random sample of 17 observations from the second population revealed a sample mean of 342 and a sample standard deviation of 15. At the .10

Help solving these Probability Problems

1) Ms. Maria Wilson is considering running for mayor of the town of Bear Ghulch, Montana. Before completing the petitions, she decides to conduct a survey of voters in Bear Gulch. A sample of 400 voters reveas that 300 would support her in the November election. a) estimate the value of the population proportion. b) comput

Hypothesis Testing with Proportions

#10 The chief of security for the Mall of the Dakotas was directed to study the problem of missing goods. He selected a sample of 100 boxes that had been tampered with and ascertained that for 60 of the boxes, the missing pants, shoes, and so on were attributed to shoplifting. For 30 other boxes employees had stolen the goods

Two-sample Dependent or Matched pairs T-test

Because of uncertainty in real estate markets, many homeowners are considering remodeling and constructing additions rather than selling. The most expensive room in the house to remodel is the kitchen, with an average cost of $23,400. In terms of resale value, is remodeling the kitchen worth the cost? The following cost and r

One-Sample T-Test Command

The national average for the price of a gallon of unleaded regular gas is $1.16. I believe the price is higher in my area of the country. I want to test my claim by randomly selecting gas prices for 25 stations in my area. The following prices are: $1.27 $1.29 $1.16 $1.20 $1.37 1.20 1.23 1.19 1.20 1.24

5 Steps in hypothesis Testing

Need help working my way through the rest of the 5 steps with the information given. The null hypothesis is the average miles per gallon of fuel used in the Toyota Highlander hybrid vehicle, ?h is higher to equal to than that of a Toyota Hylander standard eight cyclinder, ?8. The alternative hypothesis is the average miles per

Population and Sample Standard Deviation

1.)If the population standard deviation ( s) is known then we use it in calculating the z-statistic as follows. z= [Xbar - m ] / [ s/ sqrt(n) ] On the other hand if population standard deviation is unknown, we substitute the sample standard deviation (s) in place of population standard deviation in calculating the z-statist

P-Value Explanation

Can you explain P- value in easy to understand terms. Statistics is very confusing for me and I feel lost, any help you can give me will be greatly appreciated.

F-Distribution question

(See attached file for full problem description with proper symbols) Samples of sizes 10 and 18 taken from two normal distributions gave and Using the F distribution, show that F = 0.49 and 1/F = 2.04, and test the hypothesis

Hypothesis testing and Confidence Limits

Given that X is a normal variable and given the sample values x̄ = 42, s = 6, n = 20, (a) test the hypothesis that μ = 44 by showing that student t = -1.49 and (b) show that 95% confidence limits for μ are 39.2 < μ < 44.8.

Hours spent at desktop computers

The manager of a computer software company wishes to study the number of hours senior executives spend at their desktop computers by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hours s

T-test statistics questions

1. The following are the GMAT scores and the GPA's of a random sample of 6 students in a graduate school. During a "cram" weekend the students learned several GMAT applications. With a 0.05 level of significance did the GPAs increase? BEFORE AFTER

Hypothesis testing

A national survey of restaurant employees found that 75% said work stress had a negative impact on their personal lives. A sample of 100 employees from a popular restaurant chain finds that 68 answer "Yes" when asked, "Does work stress have a negative impact on you personal life?" Is there a eason to believe the restaurant chain

Hypothesis testing, scatter diagrams, test statistics

(See attached file for full problem description) --- 1. The manager of the BiLo Supermarket in Mt. Pleasant, Rhode Island, sampled the following information on the number of times a customer visits the store during a month. The responses of 51 customers were. If EXCEL is used, please import the information into this test d

Sample Size Statistic

HI, I am having difficulty understanding statistics. I had just completed a paper in which I made a statistical comparison using gas prices in 1975 and 2006. The gas prices were in today's dollars. I need to do a small sample size statistic with the same info and I'm lost. Could you walk me through this with the 5 step hypoth