Monday, October 24, 2011 Honors Statistics warm-up Suppose I say that I will drop the lower of your two tests. You got a 90 on quiz 1 and an 80 and quiz 2. Just as you’re about to drop quiz 2, I drop a bomb on you: I will grade “on a curve”, i.e., I will standardize the scores to decide which is the lower one. If the mean on the first test is 88 with a standard deviation of 4 and then mean on the second was a 75 with a standard deviation of 5, which test should you drop? Welcome to college!
Monday, October 24, 2011 Quiz # 2 1. What is the name of the Greek letter σ? What does it stand for in statistics? 2.From the following data set listed below, (a) draw a dot plot, (b) calculate a 5-number summary, (c) list the mean, standard deviation, range, and IQR, and (d) do a box plot including the upper fence, lower fence, and outliers. 3.What is n for the data set? 3, 8, 4, 3, 7, 9, 3, 1, 2, 1, 2, 11, 12, 13, 3, 2, 3, 3, 3, 4, 5, 1, 2, 8, 12, 15, 3, 2, 3, 10
Tuesday, October 25, 2011 Honors Statistics warm-up 1.How many euros is $2,500 if the conversion rate is $1.34=1€? 2.How many inches are in a kilometer? 3.Express in meters the distance from earth to Proxima Centauri if the distance is 4.2 light years (recall that the speed of light is approximately 300,000 meters per second)
Wednesday, October 26, 2011 Honors Statistics warm-up 1.Rupert Murdoch and his family control 40% of News Corp., and a friendly Saudi prince owns another 12%. At a shareholder’s meeting, dissident shareholders voted 33% of all shares against Murdoch’s son James as a member of the board of directors. Assuming that the Murdoch family and the Saudi prince voted all their shares in favor of James, what was the percentage in favor of ousting James from the board as a percentage of the non-Murdock controlled shares? 2.A runner ran the 800 meter “dash” in 145 seconds. At the meet, the average time was 137.6 seconds, with a standard deviation of 4.3 seconds. Express the runner’s time in units of standard deviation. How did the runner do compared to the other contestants. 3.In the same race as described in question 2, another runner ran 1.83 standard deviations under the mean time. What was her time in the race?
Thursday, October 27, 2011 Honors Statistics warm-up 1.Zlotnys are convertible only to British Pound Sterling at the rate of 16.34 zlotny for each British Pound. Each British pound in turn is worth $1.61US, and the current exchange rate between euros and dollars is 1:1.41. What is the value of 255 zlotnys in terms of Euros? 2.A runner completes a race at 1.7 standard deviations below the mean time of 38.8 seconds, with σ = 4.2 seconds. How many seconds from the mean time did the runner finish?
Friday, October 28, 2011 Honors Statistics warm-up 1.How many seconds are in 47 days? 2.How many ounces are in 2.5 kilos? 3.Assume a normal distribution of driving times where the average is 20 minutes and the standard deviation is 2 minutes. Calculate the percentage of times that: 1.Your driving time is more than 16 minutes. 2.You arrive no later than 22 minutes. 3.You are more than 6 minutes later than average 4.You are 4 minutes or more earlier than the average