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Hypothesis Testing

Statistical inference: Gander Mountain store in Frogtown, IL

Scenario 1 The manager of the Gander Mountain store in Frogtown, IL, believes that his prices for ammunition are lower than the prices of his primary competitor in the hunting equipment market, Cabela's. He would like to be able to provide evidence to support this assertion. - What are the Gander Mountain manager's null and al

Research Methods

You are a research analyst with a large research and development firm, Akron Research. Your firm performs studies and analysis for companies that need product, process improvement, manufacturing, and consulting research services. You have been assigned to develop a comprehensive research strategy and plan and develop a propo

Biostatistics: Clinical trials

The table below summarizes baseline characteristics on patients participating in a clinical trial. a) Are there any statistically significant differences in baseline characteristics between treatment groups? Justify your answer. b) Write the hypotheses and the test statistic used to compare ages between groups. (No cal

ChiSquare, Regression, Etc

Question 1 A goodness of fit test is to be performed to see if Web Surfers prefer any of four Web sites (A, B, C and D) more than the other three. A sample of 60 consumers is used. What is the expected frequency for Web site A? 1/4 20 15 10 30 Question 2 A variable contains five categories. It is

Null, t-score, pvalues

One of the most commonly used statistical techniques is the comparison of two means, also known as the t-test (for this you need quantitative, or interval level data). If you used the same data to compare means with equal sample sizes, how would the results compare if you used the paired sample, independent sample equal varianc

Ioccurrence of presenile dementia and a family history

A case-control study of presenile dementia identified 176 clinically diagnosed patients aged below 65 years from hospital records. Each case was individually paired with a community-sampled control of the same sex and age. Steps were taken to ascertain that each of the controls did not suffer from dementia. One of the risk fa

The Association Between PIR and Plasma Amphetamine Level

See the attached file. In a study of the relationship between amphetamine metabolism and amphetamine psychosis, twenty habitual amphetamine users were tested and given a psychosis intensity rating (PIR). Plasma amphetamine levels (mg/ml) were also measured for these patients. The data is summarized in the table below. The

Comparing the concentrations of two types of aspirin

One method for assessing the bioavailability of a drug is to measure its concentration in blood and/or urine samples at certain points in time after administering the drug. Suppose we want to compare the concentrations of two types of aspirin (types A and B) in urine samples taken from the same person, 1 hour after he or she ha

The Association Between Maternal Age and Birth Weight

See the attached file. A small pilot study is being conducted to determine the association between maternal age and birth weight. First, from all the single births in 2009 at Hospital X with mothers aged less than or equal to 20 years, we randomly selected 15 records. We also selected randomly 17 records from all the sing

Statistical Significance

Discuss the concept of statistical significance, including your understanding of what it means, why it is important, and how it can be used.

Statistics Case Study Problem

A researcher predicts that watching a film on institutionalization will change students' attitudes about chronically mentally ill patients. The researcher randomly selects a class of 36 students, shows them the film, and gives them a questionnaire about their attitudes. The mean score on the questionnaire for these 36 students i

Reject or Fail to Reject the Null Hypothesis

A researcher predicts that watching a film on institutionalization will change students' attitudes about chronically mentally ill patients. The researcher randomly selects a class of 36 students, shows them the film, and gives them a questionnaire about their attitudes. The mean score on the questionnaire for these 36 students i

Treaded Discussion

Examples of Six Sigma Tools for Statistical Significance. Cite an example of your experience with applying Six Sigma tools for Statistical significance in the workplace. If you do not have an actual example, suggest a situation or context in which the tools would provide valuable quality improvement help. Use the classic que


Harris, Schoen, and Hensley (1992) conducted a research study showing how cultural experience can influence memory. They presented participants with two different versions of stories. One version contained facts or elements that were consistent with a U.S. Culture and the second version contained material consistent with a Mexic

Baseball 2010 data

Refer to the Baseball 2010 data, which reports information on the 30 Major League Baseball teams for the 2010 season. Prepare a report on the variable team payroll that specifically addresses each of the following questions. a. Around what values do the payrolls tend to cluster? What are the mean and median of payroll? Is one

Hypothesis Testing: Finding the Number of Resignations

Please help with the following statistics problem. Please provide step by step calculations in Excel. The personnel department reported 60 resignations during the last year. The following data shows the seasons in which they occurred: Season.......................Number of resignations Winter.........................10

Calculating the P-Value in Excel Based on the Null hypothesis T-Test

A major manufacturer of golf equipment seeks to improve its market share by introducing a golf ball that is less likely to slice when hit. The company's research and development group has been experimenting with dimple patterns that promote straight flight, and have achieved some degree of success. The vice president of marketin


1.) The following sample was obtained from a population with unknown parameters. Scores: 6, 12, 0, 3, 4 Compute the sample mean and standard deviation. (Note that these are descriptive values that summarize the sample data). Next part of question is to compute the estimated standard error for M. (Note that this is an

Multiple t test based questions

1.) A spelling test is given to random samples of size 6 from executive secretaries at each of two large insurance companies. The results (in errors/document are: Company A Company B Subject 1 5 3 2 9

Statistical Problems

1.) Two candidates for governor participated in a televised debate. A political pollster recorded the preferences of 500 registered voters in a random sample prior to and after the debate: Preference After Debate Preference Prior

Statistical Problems

1. Although many people think they can put a meal on the table in a short period of time, an article reported that they end up spending about 40 minutes doing so. Suppose another study is conducted to test the validity of this statement. A sample of 25 people is selected, and the length of time to prepare and cook dinner (in min

Hypotheses for Mutual Funds

Mutual funds are classified as load or no-load funds. Load funds require an investor to pay an initial fee based on a percentage of the amount invested in the fund. The no-load funds do not require this initial fee. Some financial advisors argue that the load mutual funds may be worth the extra fee because these funds provide a

Hypothesis Test for Consensus Estimate

On Friday, Wall Street traders were anxiously awaiting the federal government's release of numbers on the January increase in nonfarm payrolls. The early consensus estimate among economists was for a growth of 250,000 new jobs (CNBC, February 3, 2006). However, a sample of 20 economists taken Thursday afternoon provided a sampl

Null hypothesis

You're trying to explain null and alternative hypotheses to one of the senior managers at Company W and he's not "getting it" when you use snack food sales. Help him by thinking about a business problem in another organization or department. Formulate a null hypothesis and the corresponding alternative hypothesis that could be t

The Role of Mental Health in Physical Health

'Does mental health play a role in physical health?' 1. Briefly remind us of the two variables in your correlation and the operational definition of each. 2. State the null hypothesis and the alternative hypothesis (be sure to clearly label each one) for your correlation. 3. Explain what it would mean if we rejected the nu

Hypothesis Testing Using One Sample

Scenario 1 The vice president of operations for a veterinary supply company has designed a new quality control process that she believes will significantly reduce the reject rate in the packing line for bottles of equine glucosamine from its historical level of 32 units per 1,000. She now wants to implement a pilot of this pr

Hypothesis Testing of Mean..

Historically the average age of European soccer players is reported as 26 years with a standard deviation of 4 years. A random sample of 81 European professional soccer players has an average age of 27 years. We would like to decide if there is enough evidence to establish that average age of European soccer players has increase