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Hypothesis Testing

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: μ= μ0, then Ha : ___________________________________ . 21. Given H0: μ ≤ μ0, then Ha : ___________________________________ . 22. Given H0: μ ≥ μ0, 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 x̄ = 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, standard error, critical value

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

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

Personality Assessment Instrument: obsessive-compulsive disorder

Select one psychological personality assessment instrument or inventory to serve as the basis of this assignment. Explore the psychological literature to find three to five articles that test the use of this inventory or assessment on obsessive-compulsive disorder. Include the following information: o Describe the

Statistics: 4 problems

4. Explain why t distribution tends to be flatter and more spread than the normal distribution. 12. Last fall, a sample of n = 36 freshmen was selected to participate in a new 4-hour training program designed to improve study skills. To evaluate the effectiveness of the new program, the sample was compared with the rest of th

Hypothesis Testing, Power of Hypothesis Testing & Cohen's d

2. The value of the z-score in a hypothesis test is influenced by a variety of factors. Assuming that all other variables are held constant, explain how the value of z is influenced by each of the following. a. Increasing the difference between the sample mean and the original population mean. b. Increasing the population

Test the hypothesis: Obtain test statistic & p-value

To test the hypothesis that students who finish an exam first get better grades, Professor Barker kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of 2

Hypothesis & P Value

Hypothesis, Null and Alternative, & P-values Q1: What is a p-value in testing hypothesis? Q2: How does this p-value help us to decide to/not to reject a Null hypothesis? What might happen if we do not use this p-value in particular, when we are rejecting a Null hypothesis? Q3: What are the limits of these p-values t

Hypothesis: Null and Alternative

1: How do you decide your null and alternative hypotheses? 2: How do you as a researcher decide the confidence level? What factors do you consider to make that decision? 3: How do you decide on the type of test? For example, should you use z-test, t-test, or non-parametric test that we will study later on [such as x^2 test, F-

P test value and confidence interval for mating behavior of the Mormon cricket

In a field study of mating behaviour in the Mormon cricket, a biologist noted that some females mated successfully while others were rejected by the males before coupling was complete. The question arose whether some aspect of body size might play a role in mating success. The accompanying table summarizes measurements of head

Hypothesis Test

The duration of human gestation is on average 40.5 weeks. In a maternity ward, we note the gestational age of 100 consecutive newborns. The sum of these ages is equal to 3850 weeks and the standard deviation is 5 weeks. We believe that it is a ward for premature births. Do we have enough evidence to support our claim? Make su