Statistics Math 300 Exam

Question #2 / 20

The stem-and-leaf display below gives the fuel efficiencies (in miles per gallon) for a sample of new cars. Use the display to answer the following questions.

Question #3 / 20

The Moon Illusion refers, roughly speaking, to the common experience that the moon appears larger (and closer to us) when it is near the horizon than when it is at its zenith. Wishing to investigate the causes of the illusion (which are still debated), we have designed an experiment in which participants must adjust the diameter of a variable circular light placed at eye level to match the diameter of a fixed circular light placed well above eye level. (See, for example, Kaufman, L. & Rock, I. (), "The moon illusion thirty years later," chapter in M. Hershenson (Ed.) The Moon Illusion, Hillsdale, NJ: L. Earlbaum.) We have tested participants and recorded for each participant her experimental "adjustable/ fixed ratio." Our data are summarized in the following histogram

Question #8 / 20

There is some evidence that, in the years , a simple name change resulted in a short-term increase in the price of certain business firms' stocks (relative to the prices of similar stocks). (See D. Horsky and P. Swyngedouw, "Does it pay to change your company's name? A stock market perspective," Marketing Science v., pp. .)

Suppose that, to test the profitability of name changes in the more recent market (the past five years), we analyze the stock prices of a large sample of corporations shortly after they changed names, and we find that the mean relative increase in stock price was about %, with a standard deviation of %. Suppose that this mean and standard deviation apply to the population of all companies that changed names during the past five years. Complete the following statements about the distribution of relative increases in stock price for all companies that changed names during the past five years.

Question #9 / 20

Below are numbers of hours that a sample of recent college graduates reported working last week.

61, 45, 53, 39, 36, 53, 55, 38, 69, 60, 43, 40, 59, 62, 56, 48, 47, 58, 57

Question #10 / 20

Three distributions, labeled (a), (b), and (c), are represented below by their histograms. Each distribution is symmetrical and is made of measurements. Without performing any calculations, order their respective standard deviations  ,  , and  .

Question #16 / 20

Recently, Hector ran for president of the local school board. Of those who voted in the election, had a high school diploma, and the other did not. Hector got of the vote of those with high school diplomas, while he got only of the vote of those without high school diplomas.

Let denote the event that a randomly chosen voter (in the school board election) had a high school diploma and denote the event that a randomly chosen voter did not have a high school diploma. Let denote the event that a randomly chosen voter voted for Hector and denote the event that a randomly chosen voter did not vote for Hector.