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Hypothesis Testing

Hypothesis test for a population proportion.

A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coined biased towards heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.

Quantitative Research Methods

1. Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the days shift. Assume the populations standard deviation for the number of units produced on the days shift is 21 and is 28 on the night shift. A sample of 54 day shift workers

Hypothesis Testing Question

Does lovastatin (a cholesterol lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (averge age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. a) state the appro

Small sample hypothesis test for a population mean

How tall are college hockey players? The average height has been 68.3 inches. A random sample of 14 hockey players gave a mean height of 69.1 inches. We may assume that x has a normal distribution with σ = 0.9 inch. Does this indicate that the populations mean height is different from 68.3 inches? Use 5% level of signi

Statistical questions

1. Can the formal hypothesis testing approach be used for non parametric tests? a) How are parametric and nonparametric statistics different? b) How are parametric and nonparametric statistics similar?

Test Statistics of Consumer Products

A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of cars. In particular, each car has one tire of each brand on

Why is statistical significance not necessarily of practical important difference to a business decision? Give an example and explain. Why do statisticians play only a limited role in deciding whether statistical significance requires a business action?

Why is statistical significance not necessarily of practical important difference to a business decision? Give an example and explain. Why do statisticians play only a limited role in deciding whether statistical significance requires a business action?

Hypothesis Testing Problem ...

High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as "Low" (under 88 decibels), "Medium" (88 to 91 decibels), or "High" (92 decibels or more). There

Hypothesis Testing: Jogger Oxygen Uptake Example

A physician claims that joggers' maximal volume oxygen uptake is greater than the average of all adults. A sample of 15 joggers has a mean of 43.6 milliliters per kilogram (ml/kg) and a standard deviation of 6 ml/kg. If the average of all adults is 36.7 ml/kg, is there enough evidence to support the physician's claim at a = 0.05

Texas Study... (Please see the attached file.)

10.44 Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State t

Statistics: Accident Rate

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 low

Econometrics

Problem: 5-Dec Alaska American America West British Continental 7.74% 7.67% -0.89% -2.52% 4.12% Delta JetBlue Northwest Southwest US Airways 4.45% 3.14% 4.84% 3.53% No Change Estimate the variance of the percent change in airline stock 6-Dec

Statistics - Probability and Hypothesis Testing

1. The mean life of a computer disk drive is 2,000 hours. The standard deviation is 140 hours. Assuming the life-time of the drives to be normally distributed, find the probability of a disk drive lasting more than 1,800 hours. a. .4236 b. .9236 c. .8472 d. .5764 e. .2118 f. None of the above. 2. T

Calculation of p-value

A coin was flipped 60 times and came up heads 38 times. a) At the 0.10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. b) Calculate the p-value and interpret it.

Statistics tests of means and proportions

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 standard devi

Statistics - Testing Hypothesis (Mean)

The accompanying table shows the grades for three randomly selected samples of students in economics, statistics, and accounting classes. Test the hypothesis that the mean grades are the same for all three classes. Use .05 for the level of significance. Economics(X1 ) Statistics(X2 ) Accounting(X3 ) 80 100 95 90 90 90 70 90 88 1

Testing Null Hypothesis: Ship Building Company Example

Independent random samples were taken from normal distributions of the yearly production of ships built by the International Ship Building Company under (1) a fixed-position layout and (2) a project layout. The results are given in the accompanying table. Test the null hypothesis that the variance for the fixed-position layout i

Estimate on Quick brews weekly advertising expenditure

Coffee Times weekly advertising expenditure, Coffee Times weekly advertising expenditure (lagged), Coffee Times price index, Coffee Times price index (Lagged), and Estimate on Quick brews weekly advertising expenditure (lagged). The equation we have developed to predict effects on revenue when one or more of the independent va

What are the different types of samples?

What is an independent sample? What is a related sample? When should researchers use different hypothesis tests for independent and related samples? Is one type of sample preferable over the other?

Test the claim

I went over to our Provost last week to try to convince him that I have the ability of Extrasensory Perception (ESP). I gave him a deck of 10 cards, numbered 1 to 10, and asked him to shuffle them. Then, he would have to look at each card, and concentrate on the number, one at a time. I let him know that I could read hi

Verbal and Numerical Hypothesis

Formulate a numerical hypothesis of the statement issue. Formulate a verbal hypothesis statement regarding your research issue. The additional information is attached.