The data below are a random sample of 9 firms chosen from the “Digest of Earnings Reports” in The Wall Street Journal on February 6,1992

The data below are a random sample of 9 firms chosen from the “Digest of Earnings Reports” in The Wall Street Journal on February 6,1992:

Find the mean change in earnings per share between 1991 and 1992.
Find the standard deviation of the change and the standard error of the mean.
Were average earnings per share different in 1991 and 1992? Test at α = 0.02.

Problems: Testing Hypotheses: Two Sample Tests

Problem-01: Testing Hypotheses: Two Sample Tests

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Problem-16: Testing Hypotheses: Two Sample Tests

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Problem-17: Testing Hypotheses: Two Sample Tests

Greatyear tires currently produces tires at their Wilmington, North Carolina plant during two 12-hou...

Problem-18: Testing Hypotheses: Two Sample Tests

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Problem-19: Testing Hypotheses: Two Sample Tests

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Problem-20: Testing Hypotheses: Two Sample Tests

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Problem-24: Testing Hypotheses: Two Sample Tests)

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Problem-25: Testing Hypotheses: Two Sample Tests)

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Problem-26: Testing Hypotheses: Two Sample Tests)

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Problem-27: Testing Hypotheses: Two Sample Tests)

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Problem-28: Testing Hypotheses: Two Sample Tests)

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MacroSwift has recently released a new word-processing product, and they are interested in determini...

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A coal-fi red power plant is considering two different systems for pollution abatement. The fi rst s...

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The University Bookstore is facing signifi cant competition from off-campus bookstores, and they are...

Problem-33: Testing Hypotheses: Two Sample Tests

In preparation for contract-renewal negotiations, the United Manufacturing Workers surveyed its memb...

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Problem-35: Testing Hypotheses: Two Sample Tests

Approximately what is the prob value for the test in Self-Check Exercise 9-3 on page 448? Contact u...

Problem-36: Testing Hypotheses: Two Sample Tests

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Problem-39: Testing Hypotheses: Two Sample Tests

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Clic Pens has tested two types of point-of-purchase displays for its new erasable pen. A shelf displ...

Problem-41: Testing Hypotheses: Two Sample Tests

In 1992, a survey of 50 municipal hospitals revealed an average occupancy rate of 73.6 percent, and ...

Problem-42: Testing Hypotheses: Two Sample Tests

General Cereals has just concluded a new advertising campaign for Fruit Crunch, its allnatural break...

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Ben & Jerry's Homemade, inc. is an unconventional manufacturer of super-premium ice cream known for ...

Problem-44: Testing Hypotheses: Two Sample Tests

Students Against Drunk Driving has targeted seat-belt usage as a positive step to reduce accidents a...

Problem-45: Testing Hypotheses: Two Sample Tests

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Problem-46: Testing Hypotheses: Two Sample Tests

A buffered aspirin recently lost some of its market share to a new competitor. The competitor advert...

Problem-47: Testing Hypotheses: Two Sample Tests

Consider the data at the top of page 500. In the first three months of 1993, sales of luxury cary ca...

Problem-48: Testing Hypotheses: Two Sample Tests

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Problem-49: Testing Hypotheses: Two Sample Tests

Long Distance Carrier is trying to see the effect of offering “1 month free” with a monthly fi xed f...

Problem-50: Testing Hypotheses: Two Sample Tests

Is the perceived level of responsibility for an action related to the severity of its consequences? ...

Problem-51: Testing Hypotheses: Two Sample Tests

In October 1992, a survey of 120 macroeconomists found 87 who believed that the recession had alread...

Problem-52: Testing Hypotheses: Two Sample Tests

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Problem-53: Testing Hypotheses: Two Sample Tests

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Problem-54: Testing Hypotheses: Two Sample Tests

Fifty-eight of 2,000 randomly sampled corporations had their 1995 federal income tax returns audited...

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Ellen Singer asserted to one of her colleagues at Triangle Realty that homes in southern Durham Coun...

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The Dow-Jones Transportation Average is based on the closing prices of the common stocks of 20 airli...

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A group of British Physicians replicated a U.S. management survey of medical directors, asking which...

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Testing Hypotheses: Two Sample Tests

Problem-20: Testing Hypotheses: Two Sample Tests

Problems: Testing Hypotheses: Two Sample Tests

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