Unequal expectations? Testing decisional mechanisms for secondary effects of social origin

It is a common research practice to decompose the effect of social origin on an educational expectation into a primary effect, via academic performance, and a secondary effect, computed as the inequality that survives the control of performance. In this paper, I examine how specific decisional mechanisms described in the Cultural Capital and Rational Action theories contribute to explain the inequalities that survive the control of performance in the configuration of educational expectations. Cultural Capital Theory argues that participation in the dominant culture at schools, the endowment of educational resources and the development of skill-generating habits contribute to holding ambitious expectations over and above performance. In Rational Action Theory, students form expectations at each level of performance by gathering information, pondering benefits and costs, and evaluating the risk of academic failure and social demotion, which in turn might account for the secondary effect of social origin. Relying on Spanish data from 2018 PISA, I observe that Cultural Capital and Rational Action mechanisms are compatible in the explanation of the secondary effects of social origin, although two-thirds of that inequality remain unexplained. Nonetheless, I find differences in how those mechanisms perform in vertical (whether to enrol an educational level) and horizontal expectations (what alternative is preferred in that educational level).