Optimal information revelation in procurement
schemes.
by Gal-Or, Esther^Gal-Or, Mordechai^Dukes, Anthony
A buyer procuring a single input possesses private information
about each potential supplier's degree of fit with the buyer's
needs. She can search among suppliers either sequentially or
simultaneously. As long as the distribution of the fit parameter is not
overly skewed to the left, sharing information with suppliers yields
intensified price competition under simultaneous search. Moreover, the
buyer cannot benefit by providing suppliers additional information
beyond their own fitness parameter. Information revelation is never
optimal with sequential search.
1. Introduction
* Consider a small industrial buyer who wishes to procure a crucial
input. If certain attributes, such as workmanship or style, are not
fully specifiable and heterogeneous among potential suppliers, the buyer
faces the problem of finding the supplier who offers her the best value.
Because suppliers are differentiated, this value depends on both the
extent of fit of the supplier and the price he charges. The buyer incurs
a certain inspection cost in order to evaluate the extent of fit of each
supplier. She is too small to be able to fully impose a mechanism that
specifies the form of competition among the suppliers. However, the
buyer does have some limited commitment power that permits her to
precommit to a choice between simultaneous and sequential search. In the
former case, she samples and inspects a certain set of suppliers
simultaneously, by soliciting bids from them in the form of a request
for quotes (RFQ). In the latter case, she approaches suppliers
sequentially and, after each inspected supplier, she decides whether to
accept his offer or continue her search. Which option is best for the
buyer depends on a variety of factors, several of which we explore in
this research.
One factor that is particularly important and is our focus in this
article is the degree to which suppliers have information regarding how
well their product fits with the needs of the buyer. On the one hand, a
supplier who knows he is a good fit with the buyer's needs can
charge a premium for his advantage, leaving the buyer with little
remaining surplus. On the other hand, when a supplier knows he is a low
fit, he may lower his price in order to remain competitive. This can
induce lower prices overall if other suppliers know that low-fitting
types are still in the bidding. As we show in this article, the extent
to which information revelation benefits or harms the buyer depends on
the procurement method she chooses. Specifically, we illustrate that, if
the buyer chooses simultaneous search, she benefits if each supplier is
informed of his goodness of fit. In contrast, with sequential search,
the buyer benefits from withholding information from suppliers.
To see the intuition behind this distinction, note that, in
sequential search, each supplier makes his offer unilaterally as opposed
to the RFQ, in which supplier offers are made multilaterally. Consider a
supplier in the former who knows his type and therefore his exact worth
to the buyer. If each supplier, upon being contacted by the buyer, sets
the price to extract the buyer's entire surplus, then the buyer has
no incentive to continue her search in equilibrium. Furthermore, because
each supplier faces the buyer only if contacted, there is no incentive
on the part of the suppliers to undercut with price. Hence, it is
necessarily suboptimal for the buyer to reveal information in a
sequential search. Such revelation simply transfers informational rents
from the buyer to the supplier. In contrast, information revelation with
simultaneous search introduces two counteracting effects on the profits
of the buyer. In addition to the transfer of informational rents from
the buyer to each supplier that is still disadvantageous to the buyer,
information revelation introduces also a positive effect in the form of
intensified price competition. By revealing information with
simultaneous search, low-fitness suppliers can remain competitive with
highfitness suppliers by adjusting their bids downward. High-fitness
suppliers who know their types as well as the fact that their
competitors are also informed can anticipate intensified competition
from lower fitness suppliers, which forces them to compete more
aggressively as well.
We demonstrate that when the density function that characterizes
the distribution of the fitness parameter in the population is
nondecreasing, the positive intensified competition effect more than
outweighs the negative rent transfer effect. As a result, the buyer
benefits when each supplier knows his goodness of fit. We also show that
the buyer cannot further increase his profits by informing each supplier
not only of his own fit but that of all of his competitors in the
bidding. This result implies, in particular, that the buyer need not
establish an elaborate network of communication with suppliers that
facilitates transmitting information about competitors. Instead, it is
sufficient that the buyer provides a clear and detailed description of
the specifications of the input she wishes to procure as well as the
criteria she plans to utilize in evaluating the goodness of fit of
suppliers. Providing such a detailed description of her preferences
should facilitate each supplier to infer his own goodness of fit while
remaining ignorant of the fit of his competitors. In spite of that, our
analysis shows that suppliers compete as aggressively as they would if
they knew the extent of fit of all the competing suppliers.
Because the buyer in our model does not have the bargaining power
to fully extract the surplus of the suppliers (by posting a
take-it-or-leave-it price, for instance), her expected payoff falls
short of the payoff she could have obtained with unlimited precommitment
capabilities. We show that the reduction in expected payoff due to
limited precommitment power (i.e., only a choice between simultaneous
and sequential search) is proportional to the difference between the
expected values of the first- and second-order statistics of the fitness
parameter in the sample of suppliers inspected by the buyer.
To illustrate the setting of this paper, consider a tire
manufacturer who uses steel wires in the production process. The wires
have to be cleaned from drawing lubricants using water. Large quantities
of water are consumed in the cleaning process, implying that reusing the
water may save production costs. The manufacturer seeks to procure
filtering units to implement the cleaning process. There are different
options open to her. She can use paper filter, vacuum filter with
precoated drum, dissolved air floatation (DAF), filter press, and
combinations thereof. Filters differ in their material cost, energy
usage, cost of maintenance, and cleaning effectiveness. The manufacturer
is the only one who knows the make-up of the filter unit she prefers
best. The potential suppliers can obtain this information only if the
manufacturer chooses to reveal her preferences. In order to fully
evaluate the benefit from contracting with a potential supplier, the
tire manufacturer must individually contact each supplier, obtain a
quote, and determine the supplier's fit with respect to the
different attributes she values. This, however, is costly because the
manufacturer has to invest in some inspection process. Because suppliers
are differentiated in this way, the manufacturer selects the supplier on
other criteria in addition to quoted price. Our modeling framework
permits buyers, therefore, to choose a supplier on the criterion of
total value net of price.
The manufacturer can either approach suppliers one by one and
evaluate each fit and price sequentially or, alternatively, she can
approach a number of suppliers and request simultaneous quotes. In the
latter case, she also inspects the goodness of fit of all of the sampled
suppliers simultaneously. The manufacturer must also decide whether to
reveal information to each potential supplier about his degree of fit
with the buyer's requirements. Given that some of those
requirements can be subjective, the extent of fit of a given supplier is
private information that can only be observed by the manufacturer
herself, unless she chooses to clearly communicate to suppliers the
criteria she utilizes in evaluating the filtering units.
COPYRIGHT 2007 Rand, Journal of
Economics Reproduced with permission of the copyright holder. Further reproduction or distribution is prohibited without permission.
Copyright 2007, Gale Group. All rights
reserved. Gale Group is a Thomson Corporation Company.
NOTE: All illustrations and photos have been removed from this article.