Expert rule versus majority rule under partial information

Daniel Berend; J�rgen E. Harmse

doi:10.1007/bf01074958

Expert rule versus majority rule under partial information, II

Journal of Applied Mathematics and Decision Sciences ◽

10.1155/s1173912602000068 ◽

2002 ◽

Vol 6 (2) ◽

pp. 79-99 ◽

Cited By ~ 6

Author(s):

Daniel Berend ◽

Luba Sapir

Keyword(s):

Uniform Distribution ◽

Group Size ◽

Majority Rule ◽

Partial Information ◽

Distribution Parameter ◽

Decision Makers ◽

Independent Random Variables ◽

Expert Rule ◽

Distribution Rule ◽

Two Alternatives

The main purpose of this paper is clarifying the connection between some characteristics of a deciding body and the probability of its making correct decisions. In our model a group of decision makers is required to select one of two alternatives. We assume the probabilities of the decision makers being correct are independent random variables distributed according to the same given distribution rule. This distribution belongs to a general family, containing the uniform distribution as a particular case. We investigate the behavior of the probability of the expert rule being optimal, as well as that of the majority rule, both as functions of the distribution parameter and the group size. The main result is that for any value of the distribution parameter the expert rule is far more likely to be optimal than the majority rule, especially as the deciding body becomes larger.

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Between the expert and majority rules

Advances in Applied Probability ◽

10.1239/aap/1067436329 ◽

2003 ◽

Vol 35 (4) ◽

pp. 941-960 ◽

Cited By ~ 4

Author(s):

Daniel Berend ◽

Luba Sapir

Keyword(s):

Majority Rule ◽

Simple Majority ◽

Simple Majority Rule ◽

Expert Rule ◽

Special Cases ◽

The Family ◽

Majority Rules

Sapir (1998) calculated the probabilities of the expert rule and of the simple majority rule being optimal under the assumption of exponentially distributed logarithmic expertise levels. Here we find the analogous probabilities for the family of restricted majority rules, including the above two extreme rules as special cases, and the family of balanced expert rules. We compare the two families, the rules within each family, and all rules of the two families with the extreme rules.

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Between the expert and majority rules

Advances in Applied Probability ◽

10.1017/s0001867800012684 ◽

2003 ◽

Vol 35 (04) ◽

pp. 941-960 ◽

Cited By ~ 2

Author(s):

Daniel Berend ◽

Luba Sapir

Keyword(s):

Majority Rule ◽

Simple Majority ◽

Simple Majority Rule ◽

Expert Rule ◽

Special Cases ◽

The Family ◽

Majority Rules

Sapir (1998) calculated the probabilities of the expert rule and of the simple majority rule being optimal under the assumption of exponentially distributed logarithmic expertise levels. Here we find the analogous probabilities for the family of restricted majority rules, including the above two extreme rules as special cases, and the family of balanced expert rules. We compare the two families, the rules within each family, and all rules of the two families with the extreme rules.

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