Convergence and Persistence of Left - Right Political Orientations in the Netherlands 1978 - 1995

Theory: Two theories about trends in left-right political orientations are juxtaposed: the persistence theory claiming that left-right orientations are highly resistant to change versus the irrelevance theory anticipating a move of mass publics towards the center of the left-right continuum. Hypotheses: The left-right ideological differences between the Dutch political parties have declined since the early 1980s. We therefore assume that the left-right political selfplacements of the Dutch electorate have converged to the center position over time. Methods: Descriptive statistics and fractionally integrated time series (ARFIMA) models were used to analyze data from 921 independent national Dutch surveys conducted between 1978 and 1995. Results: The overtime distributions of left-right self-placement exhibit a depopulation of the left and right poles as people slowly gravitate to the center position. The aggregate orientations of religious and party affiliates also reveal a move to the common mid-point. Fractionally integrated time series models support the convergence thesis with right-most and left-most party affiliates converging most rapidly. However, the convergence we find may be part of a nonperiodic wave-like pattern were periods of convergence are alternated by periods of divergence. Future political conflicts may therefore again result in left-right political divergence.