Explore BrainMass

Hypothesis Testing

Critical region and critical values

Please help with the following problem. Determine the critical region and critical values for z that would be used to test the null hypothesis at the given level of significance, as described in each of the following: a. H0: m = 25 and Ha: m ¹ 25, a = 0.10 b. H0: m £ 32 and Ha: m > 32, a = 0.01 c. H0: m ³ 13 and

Hypothesis Testing

Choose a variable (such as number of daily admissions at a local theater or number of miles students have to commute daily to get to their college.) Before collecting the data, decide what a likely average might be, then complete the following: a. Write a brief statement of purpose of the study b. Define the population c.

Hypothesis Testing: Test of hypothesis for difference between means

Given the sample data below calculate the following: a. Sample Mean - Set One: ______ b. Sample Mean - Set Two:_____ c. Sample Std. Dev. - Set One: _____ d. Sample Std. Dev. - Set Two: _____ e. Sample Size - Set One: _____ f. Sample Size - Set Two: _ g. Hypothesis Test at LOS 0.01 if Set One has a higher population aver

The airline industry and overweight baggage

Airlines must be careful about the total weight of baggage carried by a plane on a commercial flight. Passengers with items exceeding the maximum single-item weight (usually about 70 pounds) must pay a fee (usually about $50.00 per item). Airlines continually monitor the proportion of overweight items in order to evaluate the ap

Randomized Complete Block Designs

For each of the following problems you are to provide the following: a) The experimental design structure (CRD, RCBD). b) The null and research hypothesis, test statistic and all important (necessary) summary statistics, rejection region and conclusion. c) Based on the results of the analysis (part b), could you have made

Numerical and Verbal Hypothesis Statement

The Production Manager at Hydro-Corn Farming, Inc. is considering hiring 15 additional laborers to harvest the corn supply during the peak season, as supply and demand are requiring. Currently, 50 laborers are harvesting a total of 1,000 ears of corn per hour. Laborers make $15.00 on overtime per hour. Laborers are having to

Statistical Analysis - Testing hypotheses by the five-step procedure

The breaking strengths of cables produced by a certain manufacturer have a mean of 1750 pounds, and a standard deviation of 60 pounds. It is claimed that an improvement in the manufacturing process has increased the mean breaking strength. To evaluate this claim, 80 newly manufactured cables are randomly chosen and tested, and

Ms. Lisa Monnin is the budget director for Nexus Media, Inc.

Please see the attached file. 1. Ms. Lisa Monnin is the budget director for Nexus Media, Inc. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample information. Sales ($) 131 135 146 165 136 142 Audit ($) 130 102 129 143 149 120 139 At the

ABC Company assembles electrical components

ABC Company assembles electrical components. Over a period of 10 days, employee John has averaged 9 rejects with a standard deviation of 2 rejects. Employee Jane averages 8.5 rejects with a standard deviation of 1.5 rejects over the same period. At the .05 significant level, can we conclude that there is less variation in the

Parkland Medical Repackaging

1. A t-test and comparison of two samples-Youth and Family and HOMES. Interpret your p-value and explain what the analysis shows practically. 2. ANOVA - interpret your p-value and explain what the analysis shows practically. Data attached.

Estimate the 'fudge' factor for passenger's weights

DB - Testing differences between population means : Read the article, Passengers face airport weigh-in. Source:, 2003. Passengers face airport weigh-in From correspondents in Washington January 29, 2003 Passengers checking in for flights on small planes may be asked to step on the scales along with their

Imported vs. Domestic Beer Prices

You want to know if there is a difference in price between imported and domestic beers. You go to your local supermarket and record the sales price and country of origin of 68 different beers. A t-test is run, the results of which appear below. Values Attached! 1.Why would it be better to use a one-tailed test in this

Western-Southern State Salary Differences in Teachers

A recent study of 100 elementary school teachers in a southern state found that their mean salary was $32,100 with a standard deviation of $3,500. A similar study of 100 elementary school teachers in a western state found that their mean salary was $ 34,500 with a standard deviation of $3,200 Test the claim that the salaries of

Gas Prices Analysis

Indicate the analytical approach and test stats that would be used to test your hypothesis on gas prices. 20 2.63 20 2.64 25 2.64 30 2.65 31 2.65 15 2.65 22 2.65 Column1 Column2 10 2.65 16 2.66 Mean 20.7 Mean 2.649 18 2.67 Standard Error 2.081932863 Standard Error 0.003480102

Hypothesis Testing, Regression Coefficient and Relationship

Please see attached file for full problem description. A researcher wants an answer to the following question: Does the correlation of .34 between extracurricular activities and academic achievement represent a true relationship. The null hypothesis is there is no relationship between extracurricular activities and academic a

Samples, Populations, Normal Distributions

1. Based on a large number of recorded birth weights, the mean birth weight of babies born in the general population of the US is established at approximately 115 ounces. A sample of 50 birth weights was drawn randomly from the population consisting of all babies born to mothers who consumed two or more drinks per day during the

Methods for Predicting Crime Rates

I'm not sure where to start. Please see attached file for full problem description. John Wood works as a ranger for the Texas state police force. Lately, he has noticed an alarming trend toward higher recidivism rates by criminals in several southwestern counties in Texas. Law enforcement agencies are concerned about the e

Quick Stab Collection Agency (QSCA), is a bill-collecting agency.

Please see attached file for full problem description and the data to do the hypothesis. Please show all work and write the analysis. Thanks Quick Stab Collection Agency (QSCA), is a bill-collecting agency. The company specializes in collecting small accounts. The marketing department has just suggested that QSCA adopt

Comparison of Annual Dividends

A random sample of 85 utility stocks was taken to compare the amount of their annual dividends to the annualized yields of the dividends. The data are given in following Table (see attachment) a. Find the correlation coefficient. b. Can we conclude that the variables are positively associated within the population of a

Find the test statistic, p-value and critical value and state a final conclusion

Find the test statistic, p-value and critical value and state a final conclusion. Caim: The mean IQ score of statistics professors is less than 120 sample data: n=40, mean of the values in a sample = 117, assume that the standard deviation = 14 and the significance level = 0.05 Calculate the test statistic ( round to ne

P-Value Method on Purchasing Textbooks

Suppose a study is conducted to test the claim, at a 0.01 significance level, that less than 75% of college students spend less than $250 per semester on text books. A survey of 700 students found that 71% spent less than $250 per semester on texts List the claim using the P-value method Determine the p-value (round to fo

Hypothesis Testing of Waiting Times at Fast-Food Chains

The waiting time to place an order at a branch of a fast-food chain during the lunch hour has had population mean of 3.55 minutes, with a population standard deviation of 1.1 minute. Recently, in an effort to reduce the waiting time, the branch has experimented with a system in which there is a single waiting line. A sample of

Graphical Devices for Checking Test Results

1. A random sample of 10 college students was drawn from a large University. Their ages are 22, 17, 27, 20, 23, 19, 24, 18, 19, and 24 years. What is the required condition to test to determine if we can infer that the population mean is not equal. What graphical device can you use to check to see if that required condition

Population Mean of Waiting Time Analysis

You are the manager of a restaurant for a fast food franchise. Last month, the mean waiting time at the drive-through window, as measured from the time a customer places an order until the time the customer receives the order, was 3.7 minutes. The franchise helped you institute a new process intended to reduce waiting time. Yo

Violation of Speed Limit Analysis

Do out-of-state motorist violate the speed limit more frequently than in-state motorists? This vital question was addressed by the highway patrol in a large eastern state. A random sample of the speeds of 2,500 randomly selected cars was categorized according to whether the car was registered in the state or in some other stat