Stat1070 assignment 2 q2, pmba 305 – module 3 & 4 quantitative

Module #3: Sampling Distributions, Estimates, and Hypothesis Testing  & Module #4: Two-Sample Tests and Simple Linear RegressionSample questions are as under:

SAMPLE QUESTIONS:

[1] In an article in Marketing Science, Silk and Berndt investigate the output of advertising agencies.  They describe ad agency output by finding the shares of dollar billing volume coming from various media categories such as network television, spot television, newspaper, radio, and so forth.

Suppose that a random sample of 400 U.S. advertising agencies gives an average percentage share of billing volume from network television equal to 7.46 percent with a standard deviation of 1.42 percent.  Further, suppose that a random sample of 400 U.S. advertising agencies gives an average percentage share of billing volume from spot television commercials equal to 12.44 percent with a standard deviation of 1.55 percent.

Using the sample information, does it appear that the mean percentage share of billing volume from spot television commercials for the U.S. advertising agencies is greater than the mean percentage share of billing volume from network television?  Explain.

[2] In March 16, 1998, issue of Fortune magazine, the results of a survey of 2,221 MBA students from across the United States conducted by the Stockholm-based academic consulting firm Universum showed that only 20 percent of MBA students expect to stay at their first job five years or more.  Source: Shalley Branch, “MBAs: What Do They Really Want,” Fortune (March 16, 1998), p.167.

a)    Assuming that a random sample was selected, construct a 98% confidence interval for the proportion of all U.S. MBA students who expect to stay at their first job five years or more.

b)    Based on the interval from a), can you conclude that there is strong evidence that less than one-fourth of all U.S. MBA students expect to stay?  Explain why.

ALL 34 QUESTIONS ARE ATTACHED HEREWITH IN SEPARATE WORD FILE.