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Hypothesis Testing

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

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

Hypothesis test

Consider the hypothesis test. Ho: p-p<0 - Ha: p-p>0 The following results are for independent samples taken from the popuulations. Sample 1 Sample 2 n=220 n=202 p=.17 p=.23 At a 95% level of confidence what is your hypothesis testing conclusion?

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


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


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

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


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

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

One Sample Hypothesis

Please review the attachment and how the findings may be used to answer the research question.

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

General Statistics

1. Z-test A researcher wishes to test the claim that the average age of lifeguards in Ocean City is greater than 24 years. She selects a sample of 36 guards and finds the mean of the sample to be 24.7 years with a standard deviation of 2 years. Is there evidence to support her claim at a 95% level of confidence? 2. T-test fo

Hypothesis Testing Widgets

You want to determine if your widgets from machine 1 are the same as machine 2. Machine 1 has a sample mean of 500 and a population standard deviation of 6 and a sample size of 18. Machine 2 has a sample mean of 500.5 and a population standard deviation of 2 with a sample size of 2. With an alpha of .05 can we claim that ther

Hypothesis Testing: Mean Number of Customers

Your population mean has always been 9 customers per hour. The sample standard deviation is 4. The sample size is 25. The sample mean is 8. .05 is your level of significance. Use your sample data to test the claim that the number of customers you are serving per hour has changed. Choose the most accurate answer to running

Statistics: Mill Valley Brewery, bank manager's system, mean body temp

See attached file. Please show all work. Consider the following hypothesis test: Ho: mu &gt;= 80 Ha: mu &lt; 80 A sample of 100 is used and the population standard deviation is 12. Compute the p-value and state your conclusion (reject or fail to reject) for each of the following sample results. Use alpa = 0.01 1. x = 7

Statistics: Inferences from Two Samples about home size and selling price

See attached data file. Home Size and Selling Prices Using the sample data that is attached, 21 homes with living areas under 2000 ft(2) have selling prices with a standard deviation of $32,159.73. There are 19 homes with living areas greater than 2000 ft(2) and they have selling prices with a standard deviation of $66,628

Statistics: Compare Variation in Two Samples of braking distances of cars

Braking Distances of Cars A random sample of 13 four-cylinder cars is obtained and the breaking distances are measured and found to have a mean of 137.5 ft and a standard deviation of 5.8 ft. A random sample of 12 six-cylinder cars is obtained and the braking distances have a mean of 136.3 ft and a standard deviation of 9.7 f

Inferences About Two Means: Independent Samples

Hypothesis Testing for Cigarette Tax: The mean tar content of a simple random sample of 25 unfiltered king size cigarettes is 21.1 mg, with a standard deviation of 3.2 mg. The mean tar content of a simple random sample of 25 filtered 100 mm cigarettes is 13.2 mg with a standard deviation of 3.7 mg. Use a 0.05 significance

Step 5 of hypothesis testing: Calculating the value of Z

The purpose of Team C's research is to determine why men receive higher salaries than women. Before researching the topic, team c will verify that women do indeed make less than men. According to the wages data set, women consist of only 3 of the top 25 salaries out of 100 samples. The mean women's salary is $24,452 with a stand

Inferences About Two Proportions

A total of 61,647 people responded to an Elle/ survey. It was reported that 50% of the respondents were women and 50% men. Of the women, 27% said that female bosses are harshly critical; of the men 25% said that female bosses are harshly critical. With this sample data with a 0.05 significance level to test the cla