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# Hypothesis Testing

### F- Test and ANOVA Analysis

See attached data file. Measuring Differences Among Three or More Means Modern software applications require rapid data access capabilities. An experiment was conducted to test the effect of data file size on the ability to access the files (as measured by read time, in milliseconds). Three different levels of data file si

### Waiting time of body shops in Bangor, Maine

Problem 1 There are four auto body shops in Bangor, Maine, and all claim to promptly serve customers. To check if there is any difference in service, customers are randomly selected from each repair shop and their waiting times in days are recorded. The output from a statistical software package is: ANOVA Source of Varia

### Single mean, one-tailed; single populations proportion, two-tailed

Need a brief example of the following: Cite an example of how you could/would apply a test of a hypothesis for a single mean, one tail test described in the lecture to real world situations? Make sure you state your hypothesis in both the null and alternate form as well as showing the hypotheses in symbol form such as Ho : u

### Hypothesis Testing of Unit Production

1. An industrial engineer at Lyons Products would like to determine whether there are more units produced on the afternoon shift than on the morning shift. A sample of 50 morning-shift workers showed that the mean number of units produced was 345, with a standard deviation of 21. A sample of 60 afternoon-shift workers showed the

### Abolition of the death penalty in 12 nations Crime rate change

There has been much debate over the use of the death penalty. Advocates of the death penalty feel that the penalty will reduce crime. However, as we have seen in recent years, it is being revealed that many innocent individuals may have been falsely convicted and sentenced to death due to prejudiced jurors and mishandling of evi

### Hypothesis for Statistics final exam scores.

In the belief that Statistics is too hard, a student claims that the mean score on a final exam is less then 70. 15 scores will be chosen at random to test this claim. Assume that scores on statistics tests are approximately normally distributed. Express the claim in symbolic form. State the null and alternative hypothesis for t

### Two sided p-value to compare Group A and Group B

A study was carried out and subjects were randomized to 2 groups: Group A: control diet group, N=154 Group B: a fruit-and-vegetable group, N=154. The 97.5% CI for mean changes in Group B minus mean change in Group A is (-4.7 to -0.9). Suppose we want to compute a two-sided p-value to compare the two groups. Without doing

### Probability Plot, Sample Size, ANOVA, & Regression

1. What are the four levels of measurement scales? Give examples of each and explain in detail. 2. Explain the use of normal probability plot to evaluate whether a set of data is normally distributed? Please discuss in detail. 3. Discuss how a sample size, n, an increase in confidence is achieved by widening the confidenc

### What is the null hypothesis for this study of psychology and biology student GPAs?

A college class believes that the average grade average of psychology students and the average grade averages of biology students are different. The class found that the actual grade averages of a sample of 8 psychology students was 3.5 and the average grade average of a sample of 11 biology students was 3.2. What is the null hy

### Measuring Differences Between Two Means: Hypothesis Testing

See attached file. Measuring Differences Between Two Means Over the past year, the Vice President of Human Resources at a large medical center has run a series of three-month workshops aimed at increasing worker motivation and performance. To check the effectiveness of the workshops, she selected a random sample of 35 emp

### Null and alternative hypothesis for t-test, state the decision

Question #1- Using your experience from previous or current employment, provide a business example where you could use a t-test to assist in a business decision. State the null and alternative hypothesis. The null and alternative should be the exact opposite of each other and the t-test will be looking for a difference between t

### Statistics: Compute mean, median, mode for a set of data using AIU's survey

Using AIU's survey responses from the AIU data set, complete the following requirements in the form of a report: Perform a two-tailed hypothesis test on the intrinsic variable AND a two-tailed hypothesis test on the extrinsic variable's data using a .05 significance level. Begin by creating a null and an alternate statement.

### Overlapping Regions

Are the following statements Ho: mu "greater than or equal to" 11 Ha: mu "greater than or equal to" 18 a valid pair of null and alternative hypothesis? A) No, there are no parameters contained in these statements B) No, the alternative hypothesis cannot contain numeric values C) No, these statements have overlap

### 10 Statistics Problems

Set up and solve each of the following problems using the Excel files. Be prepared to answer questions regarding the direction of the hypothesis test, the p-value, the decision to reject or not, and the conclusion. 1. ONE SAMPLE HYPOTHESIS TEST FOR MEAN: A bowler who has averaged 196 pins in the past year is asked to exper

### Create a test for reliability and validity for admission to a university

Imagine that you have been contracted to create a test to assist in the admission process at a university. What factors would be considered and what steps would be taken to ensure reliability and validity of this test? Explain why these factors and steps are important.

### Statistics: Caffeine consumption of a sample of 49 adult women

A summary on the daily consumption of caffeine for a sample size of 49 adult women produced: Ð? = 49 X bar = 215 mg s = 235 mg range: 5 to 1176 1. Does it appear plausible that the population distribution of daily caffeine consumption is normal? Explain 2. Is it necessary to assume a normal population distribut

### Statistics Problem

A mayoral election race is tightly contested. In a random sample of 1,100 likely voters, 572 said they were planning to vote for the current mayor. Based on this sample, what is your initial hunch? Would you claim with 95% confidence that the mayor will win a majority of the votes? Explain.

### Measuring Differences Among Three or More Means

See attached file. Measuring Differences Among Three or More Means Modern software applications require rapid data access capabilities. An experiment was conducted to test the effect of data file size on the ability to access the files (as measured by read time, in milliseconds). Three different levels of data file size w

### Differences between urban and suburban restaurants for variables

See attached data file. Assignment 6 Measuring Differences Between Two Means (1) Go to the Resources section in this syllabus and open the file restaurants.xls. This data file contains ratings for food, decor, service, and the price per person for a sample of 50 restaurants located in an urban area and 50 restaurants

### Statistics Questions: Licensed Drivers Example

Data from the motor vehicle department indicate that 80% of all licensed drivers are older than age 25. a) In a sample of n= 60 people who recently received speeding tickets, 38 were older than 25 years and the other 22 were age 25 or younger. Is the age distribution for this sample significantly different from the distributi

### Statistics on Human Body Temperture

Human Body Temperature: What's Normal? In an article in the Journal of Statistics Education (vol. 4, no. 2, 1996), Allen Shoemaker describes a study that was reported in the Journal of the American Medical Association.* It is generally accepted that the mean body temperature of adult humans is 98.6°F. In his article, Shoemaker

### Statistics Problems 23, 27, 11, 13, 17 and 25

Problems 23 & 37 For each claim, assume the distribution of the population is approximately normal. 23. Microwave Repair Costs &#9670; A microwave oven repairer says that the mean repair cost for damaged microwave ovens is less than \$100.You work for the repairer and want to test this claim. You find that a random sample

### Proportionally Speaking: Small vs large sample. Pro-Life random sample survey

If a random sample of 10 people found that 9 were pro-life (i.e., 90%), while another random sample of 1000 people from the same population found that 550 were pro-life (i.e., 55%), which would you find more significant? Why? Offer any personal experiences where you might have trusted results from a small sample more than t

### Sethi and Seligman examine relationship between religious optimism and conservatism

Sethi and Seligman examine relationship between religious optimism and conservatism. Test differences if possible

### Statistics: Evalulating back charges for an engineering firm

An engineering firm is evaluating their back charges. They originally believed their average back charge was \$1800. They are concerned that the true average is higher, which could hurt their quarterly earnings. They randomly select 40 customers, and calculate the corresponding sample mean back charge to be \$1950. If the standa

### Article Analysis: Job satisfaction of managers in tourism in Turkey

Prepare an analysis of your selected article. Start by identifying and summarizing the hypothesis described in the article. Then explain whether the hypothesis was rejected or accepted, and what the implications of this finding are for the study. Use the following article: Job satisfaction of managers in tourism: Cases in the

### Statistics Two-factor study: Describe the mean differences

The structure of a two-factor study can be presented as matrix with the levels of one factor determining the rows and the levels of the second factor determining the columns. With this structure in mind, describe the mean differences that are evaluated by each of the three hypothesis tests that make up a two-factor ANOVA.

### 11 statistics problems: linear correlation, paired data, variance results, samples

1. Given the linear correlation coefficient r and the sample size n, determine the critical values of r and use your finding to state whether or not the given r represents a significant linear correlation. Use a significance level of .05. R = -0.8444, n=5 Critical values: r =± 0.950, no significant linear correlation

### Interpretation of the Hypothesis Test

(TCO 8) The mean age of school bus drivers in Denver is claimed to be 56.9 years. A hypothesis test is performed at a level of significance of 0.05 with a P-value of 0.03. Choose the best interpretation of the hypothesis test. Reject the null hypothesis; there is enough evidence to reject the claim that the mean ag

### Hypothesis Testing for an Oil and Lube Service

(TCO 11) A 15-minute Oil and Lube service claims that their average service time is no more than 15 minutes. A random sample of 40 service times was collected, and the sample mean was found to be 15.4 minutes, with a sample standard deviation of 3.2 minutes. Is there evidence to support, or to reject the claim at the alpha = 0.0