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Hypothesis Testing

Probability distribution and hypothesis testing

There are 4 entrances to a building in Philadelphia. The bldg maintenance super would like to know if the entrances are equally utilized. To investigate, 400 people were observed entering the building. The number using each entrance is reported below. At the .01 signficance level, is there a difference in the use of the four ent

Null and Alternative Hypothesis

Multiple Choice: All of the following are possible hypotheses surrounding nominal data except: a. The percentage of people favoring brand A is greater than the percentage favoring brand B. b. The average income of electricians exceeds the average income of carpenters. c. The number of households with term life insurance e

Null and Alternative Hypothesis

Given a two-tail test for the population mean, the null hypothesis contains a(n) __________ sign, and the alternative hypothesis contains a(n) ___________ sign. a. ¹, = b. =, ³ c. £, = d. =, ¹ Use the following information for questions 3 - 5. The Waterhole bar and grill decided to run a special offer of a fr

2 True and False questions on hypothesis testing

1) For any hypothesis test, if the value of a parameter being tested falls outside the confidence interval for the same level of a, the correct decision is to reject the null hypothesis. Is this True or False? 2) Irrespective of whether a two-tail or one-tail test is being conducted in order to compare two population means, t

Null and Alternative Hypothesis

The educational testing service (ETS) designs and administers the SAT exams. Recently the format of the exam changed and the claim has been made that the new exam can be completed in an average time of 120 minutes. A sample of 50 new exam times yielded an average time of 115 min. The standard deviation is assumed to be 2 minu

Statistics help: Null and Alternative Hypotheses

In an attempt to improve quality many manufacturers are developing partnerships with their suppliers. A local fast food burger outfit has partnered with its supplier of potatoes. The burger outfit buys potatoes in bags that weigh 20 lbs. It does not wish to accept underweight bags of potatoes. A sample of 40 bags shows an ave

Null and Alternative Hypothesis

10.21 An automobile company thinks that with new designs, it scars will last longer before having a problem. For this reason the company wishes to extend the warranty that comes with the vehicle in hopes of attracting more customers. Before making this change the idea is tested. Prior to the design changes, the cars lasted on th

Null and Alternative Hypothesis

A vending machine that dispenses coffee into cups must fill the cups with 7.8oz of liquid. Before selling the vending machine to a college or business, the company tests the machine to be sure it is dispensing an average amount of 7.8oz of coffee. A sample of 20 amounts is shown below. The amount of coffee dispensed is assumed

Statistic problem

Test the hypothesis that there is no difference in the age of the death for the United States Presidents and Vice Presidents. (see attachment for full question)

Hypothesis Tests

Problems are attached in word format. The questions are posted below to provide quicker review. Thanks, Q1) Does gender impact the use of electronic mail (e-mail)? An insurance company studied the use of e-mail in its organization by counting the number of business-related e-mails generated by 10 men and 10 women matched o

Statistic Problem

The New York Stock Exchange (NYSE) consists of listing of approximately 1,500 companies, which offer shares of company stock to the public. Stockbrokers are interested not only in the individual stocks, but also in general trends established by the market as a whole. They often base inferences upon the daily closing prices of

Hypothesis Testing , Normal Distribution

1) Hypothesis Testing A. For the statement: The mean amount of Pepsi in cans is at least 12 oz. Express the null hypothesis and the alternative hypothesis in symbolic form. B. Find the z value for the following : The claim is u(mu) =12, and the sample statistics include n =36, xbar = 12.19 and s = .11 C. Determine whether

Hypothesis Testing

5. In the past it took Kim 148.4 seconds to swim 200 meters. Kim wants to know if her average has changed. She records her time on 50 randomly selected occasions and computes the mean to be 147.8 seconds with a standard deviation of 2.3 seconds. a. Perform the appropriate test of hypothesis to determine whether Kim's average t

Hypothesis Testing- 508

A. Attitude change is thought to result from the anxiety produced under conditions of cognitive dissonance. The data below represent the anxiety scores of subjects in a dissonance study. Assuming that anxiety is distributed with mean=10 and standard deviation=2 test whether this sample exhibited more anxiety than would be expect

Using proportional relationships.

Assume that male snakes of a particular species are all scaled versions of the same basic shape. (i) (a) Describe in words the sort of relationship that you might expect there to be between the volume and the length of a snake. What relationship would you expect there to be between the mass and the length of a snake ?.


A. (Ey)(Ex2)-(Ex)(Exy) / n(Ex2) - (Ex2) B. n(Exy) - (Ex)(Ey) / square root of n(Ex2) - (Ex)2 C. r= n(Exy) - (Ex)(Ey) / sq. root of [n(Ex2) - (Ex)2][n(Ey2) - (Ey)2

Hypothesis testing

21st Century Insurance Company claims that telephone calls for policy holder information are answered in at most 3 minutes. A random survey of 36 phone calls results in the mean 3.3311 and standard deviation 2.1788. Is there sufficient evidence to disprove their claim? Alpha .05

Average, Standard Deviation, Confidence Interval, Test of Hypothesis

A vendor supplies refreshments at a baseball stadium and must plan for the possibility of a World Series contest. In the accompanying table, x represents the number of games required to complete a World Series contest. P(x) is the probability that x games are required to complete the contest. x P(x) 4

Statistics Cases

A) What is the response variable and what is the factor? b) Ho many levels of the factor are being studied? c) Is there any difference in the average time to failure of the disks from the 3 different suppliers? If so, which ones are different? d) What is your recommendation to the company and why?

Diaper Hypothesis - Statistics

14.1 A diaper company is considering 3 different filler materials for their disposable diapers. Eight diapers were tested with each of the 3 filler materials and 24 toddlers were randomly given a diaper to wear. As the child played, fluid was injected into the diaper every 10 minutes until the product failed (leaked). The amount


12.17 M&M / Mars claims that at least 20% of the M&M's in each package are the new blue color. Set up the null and alternative hypotheses to test this claim. 12.21 An automobile company thinks that with new designs, its cars will last longer before having a problem. For this reason, the company wishes to extend the warranty

Tests of hypothesis: difference between means,

13.11 Top Ten Business Computability PC Connection Software Packages Price ($) Price ($) Windows 95 Upgrade 88 95 Norton Anti-Virus 59 70 McAfee ViruScan 49 60 First Aid 97 Deluxe 54 58 Clean Sweep III 37 37 Norton Utilities 68 75 Netscape Navigator 45 40 MS Office Pro 9

Explanation to "Test of hypothesis" question

10.10 In an attempt to improve quality many manufacturers are developing partnerships with their suppliers. A local fast-food burger outfit has partnered with its supplier of potatoes. The burger outfit buys potatoes in bags that weigh 20 lbs. It wishes to set up the null and alternative hypotheses to test if the bags do weigh

Z Scores and Percentiles

Z Scores and Percentiles Mary is a social worker who leads a treatment group of young adults diagnosed with chronic anxiety. Group members are selected for treatment based on their scores on a particular screening device, Anxiety Scale A. This instrument has a mean of 60 and a standard deviation of 12. Those scoring over 72

Sampling and hypothesis testing: test statistic, average length, preacher's sermons, stratified random sample, judgment sample, sample size, type of error, probability, proportion, confidence interval

1) A woman and her son are debating about the average length of a preacher's sermons on Sunday morning. Despite the mother's arguments, the son thinks that the sermons are more than twenty minutes. For one year, he has randomly selected 12 Sundays and found an average time of 26.42 minutes with a standard deviation of 6.69 min


The quality-control manager at a lightbulb factory needs to determine whether the mean life of a large shipment of lightbulbs is equal to the specified value of 375 hours. The process standard deviation is known to be 100 hours. A random sample of 64 lightbulbs indicates a sample mean life of 350 hours a. State the null and alt

Hypothesis Testing Question

School A states the average number of days missed by each student is 4.0. Office personnel randomly sampled a portion of their attendance records to determine if this claim was accurate. For the previous year, the following data was obtained from the sample group, regarding absences for that year: 4, 4, 3, 2, 6, 8, 7, 1, 9, 3, 1