Preference Ballots

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Section 1.1 Preference Ballots

To begin, we’re going to want more information than a traditional ballot normally provides. A traditional ballot usually asks you to pick your favorite from a list of choices. This ballot fails to provide any information on how a voter would rank the alternatives if their first choice was unsuccessful.

Definition 1.1.1 Preference ballot

A preference ballot is a ballot in which the voter ranks all choices in order of preference.

Example 1.1.2

Figure 1.1.3 Video solution by David Lippman

A vacation club is trying to decide which destination to visit this year: Hawaii (H), Orlando (O), or Anaheim (A). Their votes are shown below:

	Bob	Ann	Marv	Alice	Eve	Omar	Lupe	Dave	Tish	Jim
1 st choice	A	A	O	H	A	O	H	O	H	A
2 nd choice	O	H	H	A	H	H	A	H	A	H
3 rd choice	H	O	A	O	O	A	O	A	O	O

These individual ballots are typically combined into one preference table , which shows the number of voters in the top row that voted for each option:

	1	3	3	3
1 st choice	A	A	O	H
2 nd choice	O	H	H	A
3 rd choice	H	O	A	O

Notice that by totaling the vote counts across the top of the preference table we can recover the total number of votes cast: 1+3+3+3 = 10 total votes.