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Hypothesis Testing

Conducting a Discriminant Analysis

Conduct a Discriminant Analysis on the GRADUATE.sav file. Use PHD as the dependent variable and create a discriminant function to predict whether the person will finish his or her PhD. Discuss all output.

Statistical Analysis: AIU survey data for a two-tailed hypothesis test

See attached data file. 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 n

Critical value and hypothesis testing

(a) What is the critical value and how is the critical value used in hypothesis testing? (b) Look at the example in the attachment about the new drug, Releeva. In the Releeva example, the sample size is sufficiently large (100 patients), thus we can assume normality and use a Z statistic for the hypothesis testing procedur

Important information about Hypothesis Testing of Mean & Population proportion

See attached files. 1. You are the manager of a restaurant that delivers pizza to college dormitory rooms. You have just changed your delivery process in an effort to reduce the mean time between the order and completion of delivery from the current 25 minutes. From past experience, you can assume that the population st

Independence Assumptions & Proportion vs. Percentage vs. Ratio

1. When a researcher has two samples with two means, one of the assumptions for two samples is independence of between the two samples. What does this mean? What happens if the independence assumption is violated? 2. What are the differences among a proportion, a percentage, and a ratio? When would a researcher use a hypothe

Testing the Null Hypothesis: Private vs State School Example

Suppose you want to study the population of full-time college students in State X. In this state, there are 200,000 full-time college students. Out of these students,50,000 students study at private schools, and the other 150,000 students study at state schools. You have drawn a stratified sample using private school students an

Null hypothesis: Business executives owning Blackberries

Suppose you have drawn a simple random sample of 400 business executives. In this sample, 150 executives owned Blackberries. At a 95% level of confidence, test the null hypothesis that not more than 30% of business executives own Blackberries.

Test For Two Independent Samples: Delicious and fattening, Humor and memory

1. Describe what is measured by the estimated standard error in the bottom of the independent-measures t statistics. 2. Do you view a chocolate bar as delicious or as fattening? Your attitude may depend on your gender. In a study of American college students, Rozin, Bauer, and Catanese (2003) examined the importance of food a

New York study for average number of beds sampled

Question 1 The New York study indicated that the average number of beds in the sampled data was 215. It is known that the average number of beds in the population of interest is 136. Test using a two tailed hypothesis. Test the hypothesis that the mean of 215 is statistically equal to 136. That is, any difference

Days to recover from a cold; sound frequencies

A random selection of volunteers at a research institute have been exposed to a typical cold virus. After they started to have cold symptoms, 15 of them were given multivitamin tablets daily which contain 1 gram of vitamin C and various other vitamins and minerals. The remaining 15 volunteers were given tablets only containing 4

Hypothesis Testing: Engineering Firm Example

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

Hypothesis Testing: Oil and Lube Service Example

A 15-minute Oil and Lube service claims that their average service time is no more than 15 minutes. A random sample of 35 service times was collected, and the sample mean was found to be 16.2 minutes, with a sample standard deviation of 3.5 minutes. Is there evidence to support, or to reject the claim at the alpha = 0.05 level?

Interpreting a Hypothesis Test: Health Professional Poll

A poll of U.S. health professionals revealed 82% would choose the same career. In a hypothesis test conducted at a level of significance of 5%, a P-value of 0.023 was obtained. Choose the best interpretation of the hypothesis test.

Hypothesis Testing of Mean and Population Proportion

1. In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents, while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At alpha = .01, did the yellow fire trucks have a significantly


Please assist with all parts. Thank you!!! Palm Products Company has collected data on its average variable costs of production for the past 12 months. The costs have been adjusted for inflation by deflating with an appropriate price index. The AVC and associated output data are presented below: obs Q AVC obs Q A

T statistics

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 the freshman class. All freshmen must take the same English Language Skills course, and the mean score on

Introduction to the t statistics

A research would like to examine the effects of humidity on eating behavior. It is known that laboratory rats normally eat an average of µ = 21 grams of food each day. The research selects a random sample of n = 16 rats and places them in a controlled atmosphere room in which the relative humidity is maintained at 90%. The dail

Numerical and Verbal Hypothesis

Formulate both a numerical and verbal hypothesis statement regarding the wages of different ages. Wage Industry Occupation Ed South Nonwh Hisp Fe Ex Marr Age Union 19388 1 0 6 1 0 0 0 45 1 57 0 49898 2 0 12 0 0 0 0 33 1 51 1 28219 0 3 12 1 0 0 0 12 1 30 0 83601 0 5 17 0 0 1 0 18 1 41 0 29736 0 4 8 0 0 1 0 47 1 61 1 5023


An automobile assembly line operation has a scheduled mean completion time of 2.2 minutes. Because of the effect of completion time on both preceding and subsequent assembly operations, it is important to maintain the 2.2 minute mean completion time. A random sample of 45 assemblies resulted in the completion times shown in the

Compute the Power of the Test .

A researcher is evaluating the influence of a treatment using a sample selected from a normally distributed population with a mean of u = 80 and a standard deviation of o= 20. The researcher expects a 12 point treatment effect and plans to use a two-tailed hypothesis test with a = .05. a. Compute the power of the test if

Point estimate/hypothesis testing...

1. Which of the following is not a characteristic of the normal probability distribution? a. The mean, median, and the mode are equal b. The mean of the distribution can be negative, zero, or positive c. The distribution is symmetrical d. The standard deviation must be 1 e. None of the above answers is correct. 2. Whic

Perform the appropriate hypothesis test using alpha = .05

Problem 3 A sales manager wants to know if the sales productivity of her east region is greater than the sales productivity of her west region. The results of a sample of 12 salespersons from the east region and 16 salespersons from the west region are shown below. Perform the appropriate hypothesis test using alpha = .05


9.54 - Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standa


1. A researcher is investigating the effectiveness of a new study-skills training program for elementary school children. A sample of n =25 third-grade children is selected to participate in the program and each child si given a standardized achievement test at the end of the year. For the regular population of third-grade child