Introduction to Statistics (MAT/SST 115.03 2008S)

R notes for Activity 27-7: Draft Lottery

Have we overwhelmed you with data yet? I hope not. Anyway, let's load the data and check for potential problems. I've separated the data into two files.

Draft1970 = read.csv("/home/rebelsky/Stats115/Data/Draft1970.csv")
Draft1971 = read.csv("/home/rebelsky/Stats115/Data/Draft1971.csv")

Let's check the column (variable) names for the data set.

> names(Draft1970)
[1] "Month"        "Day.of.Month" "Day.of.Year"  "Draft.Number"
> names(Draft1971)
[1] "Month"        "Day.of.Month" "Day.of.Year"  "Draft.Number"

Some notes on the data: The 1970 data have a draft number for February 29, since they were drafting people born in a number of different years. The 1971 data do not have a draft number for February 29 because they were only for men born in 1951, which did not have a February 29. In case you care, the lottery the authors are describing as conducted in 1970 was actually held on December 1, 1969 to determine the order for those to be drafted into service in 1970, and the “Data for 1971” are for a lottery held in 1970 to determine the order for those to be drafted into service in 1971. The authors note that is the source of their data, so I trust the dates on that page for these corrections.

27-7 a. Your draft number

You will find it easiest to determine your draft number by opening the data set in the editor.


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Samuel A. Rebelsky,

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