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Hypothesis Testing

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.

Baseball 2010: Test of hypothesis

Refer to the Baseball 2010 data (attached), which reports information on the 30 Major League Baseball teams for the 2010 season. a. Conduct a test of hypothesis to determine whether the mean payroll of the teams was different from $80.0 million. Use the .05 significance level. b. Conduct a test of hypothesis to determine w

Quantitative Methods and Analysis

Using AIU's survey responses from the AIU data set, can you please help me complete the following requirements: TEST #1 Perform the following two-tailed hypothesis test, using a .05 significance level: â?¢Intrinsic by Gender â?¢State the null and an alternate statement for the test â?¢Use Microsoft Excel (Data

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

Null and Alternative Hypotheses

At one school, the average amount of time that tenth-graders spend watching television each week is 18.4 hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal wants to perform a hypothesis test to determine whether the average amount of time spent watching

Null Hypothesis: Paranormal Researcher

A skeptical paranormal researcher claims that the proportion of Americans that have seen a UFO is less than 1 in every one thousand. State the null hypothesis and the alternative hypothesis for a test of significance.

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

Statistics

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

Hypothesis Testing for tap vs. bottled water

I conducted a hypothesis testing on bottled water vs tap water. I had one participant and 30 trials over a period of 3 days. The subject successfully identified tap vs water 14 times. I need to know how to calculate this data using Z and p value calculations in excel (or any statistical calculation) and be able to explain the da

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

Use critical value to evaluate the null hypothesis

Choo Choo Paper Company makes various paper products. One of their products is a 30 mils thick paper. In order to ensure that the thickness of the paper meets the 30 mils specification, random cuts of paper are selected and the thickness of each cut is measured. A sample of 64 cuts had a mean thickness of 30.3 mils with a standa

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

Statistics

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

Comparing Populations Using Statistical Inference

Sammy, the owner of a fast food chain called Sammy's Subs, wants to know whether the levels of daily sales are different between his shop in Edina and the one in Richfield. He records sales in each shop for a month, in the Sammy's Subs Sales Data Excel file. Use the data in this file to determine whether sales levels are differe

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