ref Tideman and Tullock, 1976, A New and Superior Process ..., JPE 84 (Dec).

T&T were not the first to develope demand revelation (DR).  Vickrey and
especially Edward Clarke developed it previously, but T&T brought it to
academic attentinon.  Clarke dealt with the optimal amount of a single good. 
T&T deal with a choice between two options.

Each voter offers Sa the amount he would pay to have A instead of B and Sb
what he would pay to have B instead of A.
Whichever sum of offers is greater determines the choice.
The actor who changes the outcome must pay abs(Sa-Sb, not including his
offer).
But this T&T process does not say how A or B will be paid.  It is therefore
incomple, unless the good is free, and the only cost is that of not obtaining
one's favored outcome.  If both goods are free, then it is not irrational to
obtain either good.

T&T discuss Clarke's article of 1971 (Public Choice 11, Fall), "Multipart
Pricing ...", there is a public good with some cost per unit.  
Note T&T, p. 1152: "The first stage is Clarke's process is to assign to each
voter his share of the total cost."

The excess payments "must be wasted or given to nonvoters to keep all the
incentives correct." (p., 1154).  In a footnote, T&T suggest that waste could
be avoided if "pairs of communities" "agree to exchange their collections of
these excess revenues."  This is in accord with my proposition that demand
revelation does NOT imply the need to waste the resources.

T&T note that demand revelation is not perfect.  For example coalitions can
distort the results.  The coalition benefit would vary with the square of the
number of members.  But majority voting also suffers from a large numbers
problem.  There is thus a case in either method for keeping the number of
participants relatively small.

T&T end by stating that demand revelation avoids the Arrow impossibility
problem by avoiding its assumptions.  So "the real problem raised by Arrow is
solved by this process."

Fred Foldvary

=====
[EMAIL PROTECTED]

Reply via email to