Intergenerational occupational mobility analyses have been developed around two analytical strands: the first is focused on the comparative analysis of patterns and rates of intergenerational occupational mobility, and the second is centered on the study of determinants of the attainment of individual status (Ganzeboom, Treiman and Ultee 1991; Erikson and Goldthorpe 1992; Treiman and Ganzeboom 1998; Erikson and Goldthorpe, 2001; Breen 2004a). These strands approach the study of social mobility from different perspectives, the first with the intention to describe the phenomenon at a macro-social level and, the second, with the aim to explain the micro-social stratification process behind the mobility system of society. In this study we applied both strands to answer our research questions.

The analysis within the first strand is focused on the study of absolute mobility and relative mobility. Absolute mobility refers, in the case of occupational mobility, to the change of occupational position between generations which is influenced by structural change (economic development, productive changes and in the structure of labor positions, and demographic change), as well as by relative mobility. The latter refers to the pattern and strength of the association between origins and occupational destinations of individuals, regardless of the effect of structural change. Relative mobility is equated with social fluidity and equality of opportunities, as it compares the opportunities of mobility between groups with different social origins, that is, it indicates the level of inequality in the competition for opportunities offered in the labor market (Breen, 2004a; Breen, 2004b; Cortés and Escobar, 2007).

Within this framework, the analyses have been performed both from an approach studying social mobility in relation to the movement of individuals in a vertical scale of occupations, as well as from another approach which visualizes the same as a movement between social classes (Hout and DiPrete, 2006). Those who argue for the first approach propose, based on empirical evidence, that the occupational structure follows a continuous hierarchical scale with differences in degree, which are not qualitative (Hout and DiPrete, 2006). The continuous occupational scale most frequently used in international studies on social mobility is the Socio-economic Index of Occupational Status (ISEI) developed by Ganzeboom, De Graaf and Treiman (1992), which measures the socioeconomic status associated to each occupation.

Meanwhile, those who adhere to the second approach, the approach of classes, argue that social stratification may be represented by means of categorical grouping, which does not necessarily have a vertical structure but rather, mainly, qualitative differences. They consider that this perspective makes possible the analysis of individual mobility within the structural context and, thus, mobility may be seen as a process of mediation between the micro and macro-social levels.

Various social classes schemes, seeking to represent the stratification in society and which result from different theoretical perspectives, have been proposed. The CASMIN scheme (Erikson and Goldthorpe, 1992),<sup>14</sup> which has been applied in most contemporary studies on social mobility at an international level, seeks to capture the differentiation in the labor markets and production units related to the distribution of life opportunities (Hauser and Warren, 2001; Breen,

> 14 The acronym refers to its creation within the project _Comparative Analysis of Social Mobility in Industrial Nations._

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