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Hypothesis Testing

Compute the Power of the Test .

A researcher is evaluating the influence of a treatment using a sample selected from a normally distributed population with a mean of u = 80 and a standard deviation of o= 20. The researcher expects a 12 point treatment effect and plans to use a two-tailed hypothesis test with a = .05. a. Compute the power of the test if

Point estimate/hypothesis testing...

1. Which of the following is not a characteristic of the normal probability distribution? a. The mean, median, and the mode are equal b. The mean of the distribution can be negative, zero, or positive c. The distribution is symmetrical d. The standard deviation must be 1 e. None of the above answers is correct. 2. Whic

Perform the appropriate hypothesis test using alpha = .05

Problem 3 A sales manager wants to know if the sales productivity of her east region is greater than the sales productivity of her west region. The results of a sample of 12 salespersons from the east region and 16 salespersons from the west region are shown below. Perform the appropriate hypothesis test using alpha = .05

Interpreting and Comparing Test Statistics: Example Problems

a) For the CD Camera problem situation: interpret the p-value you calculated, in the terms of the problem. b) For the CD Camera problem situation: compare the test statistic you calculated to the corresponding critical value (NOTE: be sure to use the value of Alpha given in the test statistic question when calculating th

Solve: Applied Managerial Statistics

Question: CD Camera produces a new camera that it claims can take an average of more than 7 photographs per second. A test of 36 randomly selected cameras yielded the following sample values: mean = 7.2 photos/sec S=.52 photos/sec. Using alpha = 0.025, determine the critical value rule.

Biostatistics Hypothesis and Level of Significance

Step 1: set up hypotheses and determine the level of significance step 2: select the appropriate test statistic step 3: set up the decision rule step 4: compute the test statistic step 5: conclusion (reject Ho or do not reject Ho; also state the conclusion in the context of the problem i.e. " We have statistically si

Formulating null and alternative hypotheses: CD camera example

CD Camera produces a new camera that it claims can take an average of more than 7 photographs per second. A test of 25 randomly selected cameras yielded the following sample values mean = 7.15 photo/sec S = .58 photo/sec. Use alpha = 0.01. Formulate the null and alternative hypotheses. Note: You will be doing several

Performaning the Z Test for Population Mean

In fiscal 1996, the U.S. Agency for International Development provided 238,300 metric tons of corn soy blend (CSB) for development programs and emergency relief in countries throughout the world. CSB is a highly nutritious, low-cost fortified food that is partially cooked and can be incorporated into different food preparations

Test the hypothesis that 40% will tune in to the 1965 Beetles concert

The producer of a TV special hopes that about 40 percent of the audience tunes in a re-release of a 1965 concert by the Beatles. A sample of 200 households revealed 60% would tune the concert. In a 0.10 significance level evidence suggests that at least 40 percent tune to the concert. Use the general format of the test hypot

Sample data to test the hypothesis with a two tailed test

A sample of n=9 score is obtained from a normal population with σ=12 and the sample mean is M=60. 1. Use the sample data to test the hypothesis with a two tailed test and α=.05 and the mean populations is ϻ=65 and ϻ=55.

Hypothesis of Two Independent Samples

During the 2008 election the following hypothesis was tested between two independent polling station as to the equality of the vote. Ho: u-u= < 0 - Ha : u-u>0 The following sample results were obtained from the two voting stations. Station-1 Station 2 n=32 n=40 x=22.2

Hypothesis Testing: Golf

Arnold Palmer and Tiger Woods are two of the best golfers to ever play the game. To show how these two golfers would compare if both were playing at the top of their game, the following data provide the results of 18-hole scores during the PGA tournment competition. Palmer Woods N=112 N=84

Hypothesis Testing with One Sample: Determining Outcome Variable

Recent recommendations suggest 60 minutes of physical activity per day. A sample of 50 adults in a study of cardiovascular risk factors report exercising a mean of 38 minutes per day with a standard deviation of 19 minutes. Based on the sample data, is the physical activity significantly less than recommended? Run the appropriat

Hypothesis Testing: Finding First Job

A University employment office wants to compare the time taken by graduates with 3 different majors to find their first jobs after graduation. The following tables lists the time (in days) taken to find their first full time job after graduation for a random sample of 8 business majors, 7 computer science majors & 6 engineering

Hypothesis Testing Statistics

A dietician wanted to test 3 different diets to find out if the mean weight loss for each of these is the same. She randomly selected 21 overweight persons, randomly divided them into 3 groups, put each group into one of three diets. The following table records the weights (in pounds) lost by each persons after being on these

5-Step Hypotesis Test: Real Estate Data

One Sample Hypothesis Testing Paper Using numerical data from one of the 2005 Real Estate data set, develop one business research question (The research question is "What Affects the Price of a Home)?") from which you will formulate a research hypothesis that will test two or more populations (HO: the price of a home is less

Comparing the mean food prices at Whole Foods and Fairway Market

A newspaper article discussed the opening of a Whole Foods Market in the Time=Warner building in NYC. The following data compared the prices of some kitchen staples at the new Whole Foods Market and at the Fairway supermarket. Items Whole Food Fairway milk 2.19 2.39

State the Null and Alternative Hypotheses

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. State the null and alternative hypotheses.

5 Step Hypothesis Test: Correlation

Consumer Reports magazine tested paints. The table below shows the overall quality score and cost in dollars per gallon. Test for a correlation. Based on these results, do you get better quality paint by paying more? Quality 90 87 87 86 86 86 82 81 78 62 61 59 23 Cost 27 32 34 30 20 19 19 36 15 39 24 25 15 (i) Te

Consumer Reports magazine tested large Plasma TV's

Plasma TV's Consumer Reports magazine tested large Plasma TV's. The table below shows the rankings of TV's by overall quality score and cost. High values are given low ranks, so the TV with a quality rank of 1 is the TV with the highest quality score, and a TV given a cost rank of 1 is the most expensive. Test for a correlati

Null hypothesis, decision rule, two-tailed test, z value

6 Marks: 1 Please answer questions 6 - 9 based on the following information. A firm has an order process time of at least 20 minutes. After a change in the process, a researcher wishes to determine if the processing time for orders in a warehouse averages less than 20 minutes, at a 99% confidence level. The researcher uses

Statistics: Current programmed text method vs computer assisted method

See attached file. Compare the proposed and current methods of instruction, an entering class of 122 students was assigned randomly to one of the two methods. One group of 61 students used the current programmed-text method and the other group of 61 students used the proposed computer-assisted method. The time in hours was re

Statistics

MEALS-ON-TRACKS Contract specifications require (among other things) that Meals-On-Tracks, Inc., deliver 14,400 combat meals with a mean weight of 8.5 ounces. You have been given a technical report with the results of a sample of 25 dry combat meals taken from today's shipment. The sample had a mean weight of 8.0 ounces and a

Behavioral statistics: Compute SS for a set of 3 treaetment means

The following data represent the results from an independent-measures study comparing three treatments. a. Compute SS for the set of 3 treatment means (Use the three means as a set of n=3 scores and compute SS) Treat the means as if they are scores and compute their mean as you would calculate the mean for the scores. Then ob

Hypothesis Testing of Mean: Year-end bonuses

Wall Street securities firms paid out record year-end bonuses of $125,500 per employee for 2005 (Fortune, February 6, 2006). Suppose we would like to take a sample of employees at the Jones & Ryan securities firm to see whether the mean year-end bonus is different from the reported mean of $125,500 for the population. A. Stat

Hypothesis

Using the data below and a 0.1 significance level test the claim that this mean amount of tar in filtered cigarettes is less than the mean amount of tar in unfiltered cigarettes. Do not assume the population standard deviation are equal. Filtered 15 17 17 12 16 3 17 17 9 14 12 13 14 15 14 15 15 16 10 15 11 Unfiltered

Standard Deviation

1. The Gibbs Baby Food Company wishes to compare the weight gain of infants using their brand versus their competitor's. A sample of 40 babies using the Gibbs products revealed a mean weight gain of 7.6 pounds in the first three months after birth. The standard deviation of the sample was 2.3 pounds. A sample of 55 babie

Statistics Conducted P-Values

A study conduced a few years ago claims adult men spend an average of 11 hours a week watching sports on tv. A recent sample of 100 adult men showed that the mean time they spend per week watching sports on TV is 9 hours. The population standard deviation is given to be 2.2 hours. a) Test at the 1% significance level whether

Hypothesis testing and statistical significance.

In an article about anti-tobacco campaigns, Siegel and Biener (1997) discuss the results of a survey of tobacco usage and attitudes, conducted in Massachusetts in 1993 and 1995; Table 4-4 shows the results of this survey. Focusing on just the first line (the percentage smoking 25 cigarettes daily), explain what this result means

3 problems

6. In 1978, a small plane slammed into a passenger jet over San Diego, killing 144 people. Langhorne Bond, then the head of the FAA, responded by proposing strict new curbs on small planes around many busy airports. Examine the following FAA data. Is there a statistically significant difference in the frequency of different