Assignment B

The data on technology firms from BusinessWeek measure company performance for the year 2009.

A. Observe the sample and describe the population the sample was likely taken from.

B. Divide the sample into Asian and non-Asian firms. Include as Asian: China, Hong Kong, India, Japan, Singapore, Korea, and Taiwan. Calculate and compare the mean revenue level for the two groups. Can we say for sure that the population mean revenue for Asian firms is different from non-Asian firms? Explain.

C. Calculate and interpret the standard deviation in revenue for Asian and non-Asian firms. Calculate and interpret the coefficient of variation for the two groups. Which type of firm exhibits greater variation in revenue? Does the comparison of standard deviations tell the same story as the comparison of coefficients of variation? Explain.

D. Generate the distribution in revenue for the full sample of firms. Use ten classes in the distribution. Set the size of each class at $10,731 million. Make the endpoint of the first class equal to $11,232 million. Graph the distribution and discuss its skewness.

E. Test the assumption that the average firm within the population had a mean revenue of 6.87 billion dollars. Construct a 90% confidence interval for the population mean revenue and discuss whether your statistics agree or disagree with the assumption.