ABSTRACT
It is generally taken for granted that first-past-the-post election systems invariably produce distorted outcomes via the translation of votes into seats, even if the theoretical basis for this is far from fully understood (despite the classic efforts of Gudgin and Taylor, 1979). In the UK, such distortion increased significantly after the substantial growth in support for the Liberals, Plaid Cymru and the SNP at the 1974 elections: Conservative and Labour vote shares fell much more precipitately than their seat allocations (Dunleavy and Margetts, 1997). The 2001 general election saw a small increase compared with 1997 in the degree of distortion (measured as the percentage of seats that would have to be reallocated in order to equate to the percentage of the votes obtained by each party) - though not quite to the peak level recorded in 1983 (Figure 1).
