Online ordering is currently unavailable due to technical issues. We apologise for any delays responding to customers while we resolve this. For further updates please visit our website: https://www.cambridge.org/news-and-insights/technical-incident Due to planned maintenance there will be periods of time where the website may be unavailable. We apologise for any inconvenience.
We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
Published online by Cambridge University Press: 27 January 2009
In a recent Note in this Journal by Gallagher and Unwin, it was stated that the element of randomness due to sampling surplus votes in single transferable vote (STV) elections ‘has long been recognized, but no previous attempt has been made to assess its impact’. This is incorrect. Work done in Australia (and reported in the leading Australian journals in their respective fields) has comprehensively dealt with this problem both in theory and practice. Since STV is practised in national elections in only three countries (Australia, Ireland and Malta, the most populous being Australia) it is surprising that contributors to, and referees of, this Journal should be unaware of such material. It was largely because of the evidence contained in these articles that the Joint Committee on Electoral Reform recommended to the Australian Parliament an amendment to the Electoral Act, to avoid the problems caused by sampling votes, by using the Gregory method of counting them. The Act was amended in this way in 1983.
1 Gallagher, Michael and Unwin, A. R., ‘Electoral Distortion under STV Random Sampling Procedures’, British Journal of Political Science, 16 (1986), 243–53.CrossRefGoogle Scholar
2 Fischer, A. J., ‘Sampling Errors in the Electoral Process for the Australian Senate’, Australian Journal of Statistics, 20 (1980), 24–39CrossRefGoogle Scholar and Fischer, A. J., ‘Aspects of the Voting System for the Senate’, Politics, 16 (1981), 57–62.CrossRefGoogle Scholar
3 Fischer, , ‘Sampling Errors in the Electoral Process’, p. 36.Google Scholar
4 K. J. Arrow has shown that given only a few, fairly weak anxioms to describe the social choice process, no voting mechanism exists that will satisfy them under all circumstances. See Arrow, K. J., Social Choice and Individual Values (New York: Wiley, 1951; revised 1963).Google Scholar
5 Gibbard, A. ‘Manipulation of Voting Schemes: A General Result’, Econometrica, 41 (1973), 587–602CrossRefGoogle Scholar and Satterthwaite, M. A. ‘Strategy-Proofness and Arrow's Conditions: Existence and Correspondence Theorems for Voting Procedures and Social Welfare Functions’, Journal of Economic Theory, 10 (1975), 187–217.CrossRefGoogle Scholar These theorems state that even in voting systems exhibiting monotonicity, there will always be occasions when some voters will gain more desirable outcomes by misrepresenting their preferences or intensity of preferences. The effect of the Arrow and Gibbard-Satterthwaite theorems is that we cannot hope to find a voting system which will have no undesirable properties. We must therefore make judgements about the relative importance of different violations of desirable properties by different voting systems. Not only is the lack of monotonicity likely to cause relatively minor distortions in STV, it is relatively insignificant compared with the extent to which strategic voting may occur in alternative systems of voting.
