The Social Impact of Computer-Mediated Voting

Arnold B. Urken

2. Electronic Voting and Options for Individuality

Voting situations are usually characterized by a group of individuals communicating with each other by casting votes to make a collective choice about a set of alternatives. This set, the agenda, may itself be the result of a collective decision made by the entire group or it may be created by one or more members. Obviously, the agenda may be manipulated to try to control the electoral outcome (Riker, 1983, McKelvey, 1973). And in certain situations, knowledge of other people’s preferences can enable one voter to manipulate the outcome (Gibbard, 1973). More commonly, alternatives may be added to the agenda to siphon off voting support from competing choices. Moreover, it is well known that if three or more alternatives are considered two at a time, the order in which the choice are paired can prevent the group from choosing the most popular choice based on complete information about voter preference orders (Farquharson, 1969). Furthermore, the rules used to represent voting information can affect the outcome (Urken, 1989).

The steps of a voting process can be summarized as follows:

  1. Voters or a subset of voters create an agenda.
  2. Each voter evaluates the choices by creating a preference order.
  3. Votes are cast according to the rules of a voting system.
  4. Votes are pooled or aggregated according to an explicit rule.
  5. A collective outcome is produced.

To appreciate the critical role of the voting system in this process, consider the scenario presented in Tables 1 and 2.

Table 1. Cardinal Preferences of Four Voters for Three Alternatives
Voters’ Cardinal Utility Ratings

Choices

Voter I

Voter II

Voter III

Voter IV

A
B
C

5
4
1

3
4
3

3
3
4

1
4
5

Table 2. Vote Allocations and Collective Outcomes Under One Person, One Vote (OPOV) and Approval Voting (AV) Methods
Voter Allocation by Method
 

OPOV

AV

Choices

A

B

C
 

I

II

III

IV

1

0

0

0

0

1

0

0

0

0

1

1

Plurality Outcome: C
Majority Outcome:
Indecision

I

II

III

IV

1

1

1

0

1

1

1

1

0

1

1

1

Plurality Outcome: B
Majority Outcome: B

Table 1 describes the preferences of four voters (I – IV) for three agenda choices, A, B, and C. The preferences are represented on a cardinal utility or ratio scale so that, for example, it is clear that voter I prefers A five times as much as C. Also, it is clear that A and B are tied in voter III’s preference ordering. Table 2 shows the vote allocations that can be expected when the voting information presented in Table 1 is filtered through two voting systems. Each voting system is characterized by a rule for casting votes and a rule for aggregating the votes. Under a one person, one vote (OPOV) system, voters cast one vote for their most preferred choice, while under approval voting (AV), a vote can be allocated to each choice that voters approve. In this example, it is assumed that all voters express approval by casting one vote for each alternative that equals or exceeds their average utility. In other words, each alternative with a rating greater than or equal to three receives an approval vote.

Table 2 shows quite dramatically that the voting system controls the collective outcome and that voting rules are not neutral! Depending on the rules that are chosen, C, B, or an indecisive outcome will be produced.

Before considering how computer-mediated voting might change this process, it should be noted that there is no agreement on the definition of a “good” voting system. Some analysts maintain that the choice of a voting system is based solely on taste, though when a specific, common collective decision task is at issue, different systems can be compared in terms of their efficiency in producing the desired result (Riker, 1983, Urken, 1988). Yet even here, the problem is complicated by the fact that more than one system may yield the same result. Nevertheless, if voting systems are simply considered to be tools for pooling information, we can avoid the trap of presuming that a single system is necessarily best (Niemi and Riker, 1975).

Now let us examine the issues of privacy, asynchronicity, reliability, and decision support in the context of this voting scenario.

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