Mobility comparisons: does using different measures matter?

In this paper we review alternative measure of intergenerational mobility, emphasizing the distinction between absolute, relative and ordinal mobility. We then compare the performance of various mobility indices using real data. From Treiman and Ganzeboom (1990) dataset we compare the degree of occupational and educational intergenerational (father-son) mobility in 16 countries in a single year (comprised between 1968 and 1982). From three Bank of Italy surveys (1993-1995-1998) we obtain a comparable measure of social prestige and we show that intergenerational mobility in Italy across regions or age cohort exhibits different trends according to different indicators. We suggest that ordinal relative and absolute measures provide divergent indications whenever we compare mobility data with markedly different marginal distributions.