1. Describing Distributions with Numbers ESS chapter 2 © 2013 W.H. Freeman and Company

2. Measuring Center Find the median of the following 9 numbers: 43 54 55 63 67 68 69 77 85 a) 65 b) 64 c) 67 d) 64.6

3. Measuring Center (answer) Find the median of the following 9 numbers: 43 54 55 63 67 68 69 77 85 a) 65 b) 64 c) 67 d) 64.6

4. Measuring Center Consider the data 43 54 55 63 67 68 69 77 85 Suppose that the last value is actually 115 instead of 85. What effect would this new maximum have on the median of the data? a) Increase the value of the median. b) Decrease the value of the median. c) Not change the value of the median.

5. Measuring Center (answer) Consider the data 43 54 55 63 67 68 69 77 85 Suppose that the last value is actually 115 instead of 85. What effect would this new maximum have on the median of the data? a) Increase the value of the median. b) Decrease the value of the median. c) Not change the value of the median.

6. Measuring Center Consider the data 43 54 55 63 67 68 69 77 85 Suppose that the last value is actually 115 instead of 85. What effect would this new maximum have on the mean of the data? a) Increase the value of the mean. b) Decrease the value of the mean. c) Not change the value of the mean.

7. Measuring Center (answer) Consider the data 43 54 55 63 67 68 69 77 85 Suppose that the last value is actually 115 instead of 85. What effect would this new maximum have on the mean of the data? a) Increase the value of the mean. b) Decrease the value of the mean. c) Not change the value of the mean.

8. Measuring Center If the distribution is exactly symmetric, what can be said about the median and the mean of a set of values? a) They are exactly the same. b) The mean is larger than the median. c) The mean is smaller than the median. d) Nothing can be said.

9. Measuring Center (answer) If the distribution is exactly symmetric, what can be said about the median and the mean of a set of values? a) They are exactly the same. b) The mean is larger than the median. c) The mean is smaller than the median. d) Nothing can be said.

10. Measuring Center For data on “incomes for people in the United States,” should you use the mean or the median to describe the center? a) Mean b) Median

11. Measuring Center (answer) For data on “incomes for people in the United States,” should you use the mean or the median to describe the center? a) Mean b) Median

12. Boxplots The shape of the boxplot below can be described as: a) Bi-modal b) Left-skewed c) Right-skewed d) Symmetric e) Uniform

13. Boxplots (answer) The shape of the boxplot below can be described as: a) Bi-modal b) Left-skewed c) Right-skewed d) Symmetric e) Uniform

14. Center and Spread For the following distribution of major league baseball players’ salaries in 1992, which measures of center and spread are more appropriate? a) Mean and standard deviation b) Median and interquartile range

15. Center and Spread (answer) For the following distribution of major league baseball players’ salaries in 1992, which measures of center and spread are more appropriate? a) Mean and standard deviation b) Median and interquartile range