Le changement des systèmes partisans et la transformation des espaces politiques

This paper measures the extent of party system change-in terms of changes in the underlying policy space and in party positions within it-in Western European party systems. Change is measured using two directly comparable expert surveys of party positions on four "core" policy dimensions, conducted in 1989 and 2003. A distinction is made between "survivor" parties, which competed in both 1989 and 2003, "new" parties, which competed in 2003 but not 1989, and "extinct" parties, which competed in 1989 but not 2003. Principal findings concern the changing relative importance of the core policy dimensions, as well as correlations of party positions on them; secular trends in European party policy positions and, perhaps most strikingly, a distinct tendency for "new" parties to emerge and "old" parties to disappear from the relatively more extreme positions in the policy space.