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# Hypothesis Testing

### Three relevant variables and describe one operationalization

A datum (singular of data) may be either a variable or a constant, depending upon the situation. A variable is something that...well, varies, while is constant is just that. Example: In the general population, sex is a variable. In a monastery, it's a constant. Another example: In the general population, monthly pay is a variabl

### Hpothesis Testing and P-Values: Baseball salaries, wins, attendence, AL, NL

Refer to the Baseball Data, which reports information on the 30 Major League Baseball teams. In each instance provide the p-value from your work. Complete the following: a. At the .05 significance level, can we conclude that there is a difference in the mean salary of teams in the American League versus teams in the Natio

### Hypothesis Testing: Students at West Virginia sleep less

Each response must include your calculations. This problem requires you to complete all steps for the hypothesis testing process. According to a recent survey, Americans get a mean of 7 hours of sleep per night. A random sample of 50 students at West Virginia University revealed the mean number of hou

### Pilot Study for effect of a nutritional supplement on body weight: Run a test at 5%

A small pilot study is conducted to investigate the effect of a nutritional supplement on total body weight. Six participants agree to take the nutritional supplement. To assess its effect on body weight, weights are measured before starting the supplementation and then after 6 weeks. The data are shown below. Is there a signifi

### Clinical Trial: Is there a significant difference in mean HDL levels in exercise groups?

6. A clinical trial is run to assess the effects of different forms of regular exercise on HDL levels in persons between the ages of 18 and 29. Participants in the study are randomly assigned to one of three exercise groups - Weight training, Aerobic exercise or Stretching/Yoga and instructed to follow the program for 8 we

### Clinical Trial Investigations Effectiveness

3. A clinical trial is run to investigate the effectiveness of an experimental drug in reducing preterm delivery to a drug considered standard care and to placebo. Pregnant women are enrolled and randomly assigned to receive either the experimental drug, the standard drug or placebo. Women are followed through delivery and

### Fund managers believes core inflation rate would be higher

In June 2001, 38% of fund managers surveyed believed that the core inflation rate would be higher in 1 year. One month later a similar survey revealed that 22% of fund managers epected the core inflation rate to be higher in one year. Assume that the sample size was 200 in both the June and July surveys. a. Develop a point

### Differences between Statistical and Practical Significance

Hypothesis testing determines if results are statistically significant. However, marketing managers want to know if research results are practically significant. What is the difference between these two concepts? How does a researcher explain the difference to a manager? Can the size of a sample affect the difference between sta

### Statistics Practice problems: P3, P4, P5, P6

P3. People spend huge sums of money (currently around \$5 billion annually) for the purchase of magnets used to treat a wide variety of pains. Researchers conducted a study to determine whether magnets are effective in treating back pain. Pain was measured using the visual analog scale, and the results given below are among the

### Write a paper assessing technology's future effect on the workplace.

Please provide me with a simplistic approach, outline or structure for the following assignment. I will write the paper. Assignment: Write a paper assessing technology's future effect on the workplace. * Select an industry with which you are familiar. * Predict how future technology will inform, support, and poten

### Statistics: Seat belted drivers, taste of PTC, spam in email

1) The proportion of drivers who use seat belts depends on things like age, gender, ethnicity, and local law. As part of a broader study, investigators observed a random sample off 117 female Hispanic drivers in Boston; 68 of these drivers were wearing seatbelts. Give a 95% interval for the proportion of all female Hispanic driv

### Statistics week 10: 10 true false, multiple choice questions

1. Estimation with the independent-measures t statistic is used to determine how much difference there is between two treatment means or two population means. True False 2. If you are using the data from a repeated-measures study to estimate the mean difference between two treatments, the width of the confi

### Null hypothesis or research hypothesis

Research Design Considerations a. Describe some of the issues or concerns (at least three) which would be addressed in deciding how to perform a statistical test of a hypothesis: b. As an Argosy student, you are designing a training program to help develop team cohesiveness in a healthcare facility. You have a before and a

### Statistics: Given H0, what is Ha?

See attached file for clarity. Stats questions, Fill in the blanks Q20-26. 20. Given H0: &#956;= &#956;0, then Ha : ___________________________________ . 21. Given H0: &#956; &#8804; &#956;0, then Ha : ___________________________________ . 22. Given H0: &#956; &#8805; &#956;0, then Ha : ____________________________

### Mark the terms that only relate to selecting a specific test

Place an 'X' in front of those issues that only relate to selecting a specific statistical test. (Do not put an 'X' in front of items common to all tests or not applying to statistical tests.) _____ The distribution (shape) of the population (e.g., normal, skewed, flat, etc.) _____ The measurement scale/nature of the data be

### Statistics Hypothesis test for mean time, standard deviation, type II error

Executives of a supermarket chain are interested in the amount of time that customers spend in the stores during shopping trips. The mean shopping time, µ spent by customers at the supermarkets has been reported to be 35 minutes, but executives hire a statistical consultant and ask her to determine whether it can be concluded

### Multiple regression: State the conclusion of the test

Please answer 12.7(e) e. State the conclusion of the test in part (d). Review of the previous exercise and answers: 12.1 A manufacturer of industrial chemicals investigates the effects on its sales of promotion activities (primarily direct contact and trade show), direct development expenditures, and short-range research e

### Decision of Uncertainity: Bottling plant filling process

See attached file with data set. Decision of Uncertainty PLEASE SHOW ALL WORK You are the quality manager for a bottling plant. If the filling process is working as intended, cans stamped with 12 oz. will be filled with just over 12 oz. of liquid. On average, the plant owners want 12.25 oz. in each can.

### Determine the correct decision, probability value, critical value for problems

You will be asked to determine the correct decision (Reject Ho or Fail to Reject Ho) for each of the following tests of hypotheses. 1. A hypothesis test at the 0.05 level of significance with a p-value for the sample of 0.105. 2. A hypothesis test at the 0.025 level of significance with a p-value for the sample of 0.002.

### Compare three different treatments using an analysis of variance

See attached file for clarity. 12. The following data were obtained in a study using three separate samples to compare three different treatments. a. Use an analysis of variance with ? = .05 to determine whether there are significant difference among the treatments. b. Compute the value for ?2 for these data.

### Type I and Type II errors at an automobile manufacturing plant

Type I and Type II errors Managers at an automobile manufacturing plant would like to examine the mean completion time, mu, of an assembly line operation. The past data indicate that the mean completion time is 43 minutes, but the managers have reason to believe that this value has decreased. The managers plan to perform a s

### Null and alternative hypotheses

1) The EPA fuel economy rating says that the Toyota Prius hybrid car gets 48 mpg on the highway. Deborah wonders whether the actual long-term average highway mileage of her new Prius is less than 48 mpg. She keeps careful records of gas milegae for 3000 miles of highway driving. Her result is x&#772; = 47.2 mpg. What are her

### Hypothesis Testing for Studies: Example Problems

As part of a study of corporate employees, the director of human resources for PNC, wants to compare the distance traveled to work by employees at its office in downtown Cincinnati with the distance for those in downtown Pittsburgh. A sample of 35 Cincinnati employees showed they travel a mean of 370 miles per month. A sample of

### Statistics: 17 problems

The t distribution is a continuous distribution (Points : 6) True False 2. A confidence interval for a population mean (Points : 6) estimates the population range estimates a likely interval for a population mean estimates a likelihood or probability estimates the

### Degrees of freedom, mean square, point estimate

Part 1 1. Use the ANOVA table SV----SS-----DF----MS----F Between 64---------------8 Within-------------2------ Total 100----------------- SSB = 64, SST = 100, MSW = 2, F = 8 a. The number of degrees of freedom corresponding to between treatments is? b. The number of degrees of freedom corresponding to within treatments i

### Calculating Test Statistic and P-Value

5 Steps of Hypothesis testing, test that there is no difference between each set. Level of significance is .05 What type of error could be made? A 15000 16000 14000 13000 14000 13000 15000 14000 13000 14000 13000 B 15000 13000 17000 15000 14000 19000 14000 16000 19000 The answer needs t

### Five Statistics Problems: Contributions, SAT Math scores, oil output in US, domestic

See attached file for clarity. 1. According to Giving and Volunteering in the United States, 2001 Edition, the mean charitable contribution per household in the United States in 2000 was \$1623. A researcher claims that the level of giving has changed since then. State the null and alternative hypotheses using correct symbol

### Four Statistics problems: body mass index; AP opinion polls; P value where P = 0.03

1) A student reads that a 95% confidence interval for the mean body mass index (BMI) of young American women is 26.8 ± 0.6. Asked to explain the meaning of this interval, the student says, "95% of all young women have BMI between 26.3 and 27.4." Is this explanation correct? Explain your answer. 2) You ask another student to

### Taste Test for bottled v tap water, Null/Alternative Hypothesis

I conducted a blind taste test with 50 subjects (30 women, 20 men) to see if they could tell the difference between bottled and tap water. The 32 people identified what they drank correctly and 18 incorrectly. Of the 32, 20 were women and 12 were men. Of the 18, 10 were men and 8 were women. This test was conducted in one d

### Strategy for statistically testing a new diabetics drug

Let's say I have a new drug that I think helps diabetics. So I perform clinical trials in accordance with the FDA requirements. I give one randomly selected groups of diabetics the drug, and another sample gets a placebo pill. The diabetics who get the pill improve, the controls do not. I perform a t test on the data. Wh