For any electoral system, threshold of exclusion of that system has been us
ed as a measure of the degree to which parties and candidates have an incen
tive to "narrow-cast" their appeals to a limited constituency. However, we
must adjust the threshold of exclusion to take into account the fact that m
ultimember constituencies will, ceteris paribus, be larger than single memb
er constituencies. (C) 2001 Elsevier Science Ltd. All rights reserved.