CK-12 Probability and Statistics - Advanced

http://www.ck12.org Chapter 2. Visualizations of Data

TABLE2.35:(continued)

Island Approximate Area(sq.km)

Santiago 585

South Plaza 0. 13

Wolf 1. 3

Figure:Land Area of Major Islands in the Galapagos Archipelago.Source:http://en.wikipedia.org/wiki/Gal%C3%
A1pagos_Islands

(a) Choose two methods for representing this data, one categorical, and one numerical, and draw the plot using your
chosen method.

(b) Write a few sentences commenting on the shape, spread, and center of the distribution in the context of the
original data. You may use summary statistics to back up your statements.

4. Investigation: The National Weather Service maintains a vast array of data on a variety of topics. Go to:
   http://lwf.ncdc.noaa.gov/oa/climate/online/ccd/snowfall.html. You will find records for the mean snowfall for
   various cities across the US.
   a. Create a back-to-back stem-and-leaf plot for all the cities located in each of two geographic regions.
   (Use the simplistic breakdown found at the following page http://library.thinkquest.org/4552/ to classify
   the states by region).
   b. Write a few sentences that compare the two distributions, commenting on the shape, spread, and center
   in the context of the original data. You may use summary statistics to back up your statements.

Part Two: Open-Ended Answers

1. (a)

TABLE2.36:

Class Frequency Relative

Frequency(%)

Cumulative

Frequency

Relative Cumulative

Frequency(%)

[1100-1150) 1 7. 1 1 0

[1150-1200) 1 7. 1 2 7. 1

[1200-1250) 3 21. 4 5 14. 3

[1250-1300) 3 21. 4 8 35. 7

[1300-1350) 0 0 8 57. 1

[1350-1400) 2 14. 3 10 57. 1

[1400-1450) 0 0 10 71. 4

[1450-1500) 2 14. 3 12 85. 7

[1500-1550) 0 0 12 85. 7

[1550-1600) 0 0 12 85. 7

[1600-1650) 1 7. 1 13 92. 9

[1650-1700) 1 7. 1 14 100