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IEB Working Paper 2016 / 25 THE EVOLUTION OF EDUCATIONAL INEQUALITIES IN SPAIN : DYNAMIC EVIDENCE FROM REPEATED CROSS-SECTIONS *

A lack of longitudinal data prevents many countries from estimating dynamic models and, thus, from obtaining valuable evidence for policymaking in the field of education. This is the case of Spain, where recent education reforms have targeted secondary schools, but their design has been based on incomplete information regarding the evolution of student performance and far from robust evidence concerning just when educational inequalities are generated. This paper addresses the absence of longitudinal data required for performing such analyses by using a dynamic model with repeated cross-sectional data. We are able to link the reading competencies of students from the same cohort that participated in two international assessments at different ages (9/10 and 15/16) and so identify when educational gaps – in terms of gender, socio-economic status and place of birth – emerge. In addition, we provide new evidence on the effect on achievement of the main policy used in Spain for levelling the performance of secondary school students, namely, grade retention. Our results suggest that educational inequalities in Spain originate in lower educational levels. After controlling for reverse causality, the negative relationship between grade retention and performance at the lower secondary school level persists. JEL Codes: I21, I28, I24

(Fernández 2014). The current lack of evidence for Spain may well reflect the inexistence of adequate 57 longitudinal data for assessing such questions. However, because various Spanish cohorts have participated 58 in several international assessments, we are able to exploit the strategy proposed by Moffitt (1993).

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The contribution of this article is twofold: first, it describes the evolution of educational inequalities by 60 gender, country of birth and socio-economic status (SES) in Spain between the ages of 9/10 (primary 61 education) and 15/16 (lower-secondary education). Second, it combines RCS from two different 62 international assessment tools (Progress in International Reading Literacy Study -PIRLSand the 63 Programme for International Student Assessment -PISA-), and employs a strategy that should widen the 64 number of countries capable of overcoming their data constraints through the use of RCS. In addition, and given its widespread use in Spain, we explore the effect of grade retention at the lower-secondary school 66 level on academic performance.

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This paper now proceeds as follows: Section 2 reviews the conditions that have to be met in order to 68 estimate dynamic models with RCS. Section 3 describes the data. Section 4 outlines the empirical approach 69 employed to implement the analysis and discusses the main results and policy implications. Building on the idea that the formation of human capital is a cumulative process, the learning contribution 75 of each stage in the educational process is added to the learning acquired in the previous period. Here, we 76 present a methodology for examining the impact of a set of individual and household-level characteristics 77 on reading competencies at age 15/16, considering previous achievement at age 9/10. Educational 78 inequalities may emerge during this process and understanding the evolution of these inequalities and 79 whether they are reduced or not is crucial to improving the education system. In this regard, we assume the

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Unfortunately, this data is not available for Spain so, as an alternative empirical strategy, we use data from 119 independent cross-sectional surveys conducted at primary and secondary schools. Here, we draw on the 120 previous work developed by Moffitt (1993) and, later, by Verbeek andVella (2005), which discusses the 121 conditions for the identification and consistent estimation of linear dynamic panel data models with RCS.

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The main challenge is obtaining information about , −1 in the absence of panel data.

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In the case of the first variable (month of birth), Crawford et al. (2007aCrawford et al. ( , 2007bCrawford et al. ( , 2013 and Robertson (2011) 159 report that the differences in academic performance attributable to this variable diminish as children grow

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The static specification is especially informative about the learning differences in place at age 15/16.

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However, as the specific aim of our study is to analyse how these inequalities evolve over time, the results 338 derived from the dynamic model are of more interest. Thus, if we examine the pseudo-panel estimates in 339 the second column of Table 2, we observe that previous academic achievement has a strong and significant 340 effect on secondary school performance. Gender and immigrant condition inequalities seem to accumulate 341 during secondary school, as the corresponding coefficients have similar magnitudes and are statistically 342 significant. However, the value of the coefficient for first generation immigrants falls when we control for 343 previous achievement, suggesting that the poor performance of these students is generated at an earlier 344 stage in the education system. This is consistent with the cultural assimilation hypothesis (Levels et al.

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In the dynamic specification, it should be borne in mind that the model is estimated on children from the 355 1996 birth cohort. This means we exclude children who have repeated a grade during primary school. The 356 potential sample selection bias that might be generated by this exclusion will affect our independent 357 variables and, as such, will not generate unbiased estimates, although the standard errors will be larger.

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As regards the first of these objectives, our results stress the relevance of achievement at early stages of the 381 education system: receiving early childhood education (ages 0-3) has a positive effect on reading 382 competencies at age 9/10, which in turn affects performance at age 15/16. Being able to incorporate 383 previous achievement into the analysis reveals an important finding for Spanish policymakers: SES-based 384 inequalities in reading competencies are already present at age 9/10 and appear to become more marked 385 during lower secondary schooling. The achievement gap between native and immigrant students also 386 increases between ages 9/10 and 15/16, but is narrowed when previous achievement is incorporated into 387 the static framework. These results stress the importance of early intervention for improving performance 388 during compulsory secondary education and for tackling educational inequalities. They also seem to