Explore BrainMass

Hypothesis Testing

Statistics question

A researcher hypothesizes that the lowering in cholesterol associated with weight loss is really due to exercise. To test this, the researcher carefully controls for exercise while comparing the cholesterol levels of a group of subjects who lose weight dieting with a control group that does not diet. The difference in mean chole

Hypothesis Testing: Average Speed

Question: Suppose a candidate running for sheriff claims that she will reduce the average speed of emergency response to less than 30 minutes. (30 minutes is thought to be the average response time with the current sheriff.) There are no past records, so the actual standard deviation of such response times cannot be determined.

Correlation coefficient

Please show the prcoess to work the following problems. I do not understand this area at all. Thank you for your assistaance.

Critical Values

Find the left and right critical values from the appropriate table for a 95% confidence interval for the mean when the sample size is 23.


A real estate agent wishes to see if there is a difference in appraisal values given to homes by real estate appraisers and by tax assessors. Real Estate Appraisers Tax Assessors Means $83,256 $88,354 S $ 3,142 $ 2,341 N 15 15 Find the test value. ONLY!!! In testing for a dif

Hypothesis Testing - decision making situations

Consider some decision-making situations in Business Management field of study, and describe two or more in which tests of one or more population variances are important. Use Internet resources to provide examples of situations in which population variance tests were performed. Be sure to include the url address where you found

Hypothesis Testing for Samples

You are the manager of a factory that produces Mini-Oats Cereal. The factory has an automated packaging machine that can be set at any targeted fill level between 12 and 32 ounces. Every box of cereal is not expected to contain exactly the targeted weight, but the average of all boxes filled should. At the end of every shift (8

For OTA 103997 only

Only for above listed OTA. Find the margin of error E: Grade point averages, 99% confidence, n= 75, mean = 2.76, s= 0.88

Critical Value and Decision

In an experiment to determine the effect of nutrition on the attention spans of elementary school students, a group of 15 students were randomly assignment to each of three meal plans: no breakfast, light breakfast, and full breakfast. Their attentions spans (in minutes) were recorded during a morning reading period and are sho


He U.S. Bureau of Prisons publishes data in Statistics Report on the times served by prisoners released from federal institutions for the first time. Independent random samples of released prisoners in the fraud and firearms offense categories yielded the following information on time served in months. Mean s n Samp


Please see the attached file for full problem description. --- A company that produces bias-ply tires is considering a certain modification in the tread design. An economic feasibility study indicates that the modification can be justified only if true average tire life under standard test conditions exceeds 20,000 miles. A

Hypothesis Testing

An astronomer is testing the claim that the mean brightness of a certain star is now more than 30 units. She is able to get 6 readings on the star during her experiment as shown in the table. Using α = 0.01, does this indicate a new mean brightness of more than 30? DATA Reading Brightness 1 29 2 29 3 29 4 3


Category: Mathematics > Probability Problems Subject: Test of Statistical Hypothesis Details: To whom it may concern, I need help answering these 4 problems. Please include, 1) all the steps with details on how to arrive at each solution. 2) final solution I prefer to have everything worked out in MS Word and MS Ex

Does the questionnaire seem to be effective in identifying compulsive buyers?

Use traditional method of testing hypothesis. Researchers designed a questionnaire to identify compulsive buyers. For a sample of consumers who identified themselves as compulsive buyers, scores have a mean of 0.83 and a standard deviation of 0.24. Assume the subjects were randomly selected and that the sample size was 32. U

Is the mean time greater than...

Use the traditional approach. Draw a graph showing the test statistic and critical values. Assume the population has a distribution that is approximately normal and the sample is simple random. Use the normal distribution or the Student t distribution, whichever is appropriate. Many college students require more than 4 years

Traditional hypothesis test approach

Use traditional hypothesis test approach. Draw a graph showing the test statistic and critical values. Assume the population has a distribution that is approximately normal and that the sample is a simple random sample. Use either the normal distribution or Student t distribution-check conditions to be sure which is appropriate.


I have a poor understanding of this subject. Please assist me with the attachment and explain your steps so that I can try to understand this area. Please use the traditional method becasue I can follow it a little better. Thank you for your help.

The Ferguson Paper Company

Please see the attached file for full problem description. --- (1) The Ferguson Paper Company produces rolls of paper for use in adding machines, desk calculators, and cash registers. The rolls, which are 200 feet long, are produced in widths of 1 ½, 2 ½, and 3 ½ inches. The production process provides 200-foot rolls in

Formula Z

Use formula z=(mean of values in sample - mu subscript mean of values in sample) divided by (lower case sigma divided by sqrt number of values in sample) The claim is mu = 73.4 and sample statistics include n=35, mean of values in sample = 69.5, and s=8.7.


Subject: need a paired difference statistical analysis Details: I am writing a thesis and need a paired difference statistical analysis with a confidence level at 95% with t-value for alpha of 0.25 My hypothesis is that there is a statistically significant differnce between two test scores for the following samples (


A coin tossed 10,000 times. Heads appears 5100 times. Do you think the coin is fair at the 0.05% level of significance? at the 0.01% level of significance?

For OTA 103997 or 103300 only

For OTA 103997 or 103300 only Express null hypothesis H subscript 0 and alternative hypothesis H subscript 1 in symbolic form. Use correct symbol (u(mu),p or,o(sigma)) for indicated parameter. The mean salary of professors is at least $60,000.


The American Association of University Professors conducts salary studies of college professors and publishes its finding in the AAUP Annual Report. College professors are divided into two populations: faculty in public institutions and faculty in private institutions. The summary statistics for the starting salaries of the tw