This work is in a theoretical and methodological framework derived from a deep study of the PISA (Programme for International Student Assessment). The results of this study have great impact on the educational systems. In Spain, the importance of this assessment is also high and it is being addressed from different approaches (pedagogical, sociological, psychological or economic). Recently a review of the literature about performance determinants in this international evaluation was developed (Cordero et al., In press). It summarizes the overall context in which this research was carried out. The study presented here represents a further contribution to the MESE Group (Measurement and Evaluation of Educational Systems) research line, which is coordinated by Professor José Luis Gaviria. Some of its members have published works about this topic in collaboration with other researchers; these works can be considered the background of the present paper (Lopez et al., 2009, Redondo and Navarro, 2007).

The current study aimed at identifying the effect that individual, school and family characteristics have on their performance in math and reading comprehension skills. A study of the relationship between a set of predictor variables, taking into account those included in the multilevel analysis performed by the OECD , based on the results of each of the countries participating in PISA 2009 (OECD, 2010), and reading comprehension and math.

Below are listed and briefly discussed the independent variables studied:

Compulsory schooling: Elementary Education (Fourth grade) and High School (Second grade). The introduction of Elementary Education grades (children aged 9 years) and High School grades (13 years) adds value to this research, because the studies with PISA data involve only 15 year old pupils.

Economic, social and cultural Index. It have been built following the same procedure used to calculate the OECD's Economic, Social and Cultural Status (ESCS) in PISA (OECD, 2009, p. 346). The construction of this variable takes into account three indicators: Highest parental occupational status (HISEI), The parents’ highest schooling (PARED) and home’s possessions (HOMEPOS).

First generation immigrant condition. Predictor defined by the student’s place of birth. Subjects who were born outside of Spain have been considered first-generation immigrants. Regarding this indicator, the first-generation immigrant condition and the proportion of first-generation immigrants in the school have been introduced in the model.

Sex, takes the value 0 for boys and for 1 for girls.

Reading comprehension and mathematics skills, both measured with ESP-ISA tests, are considered dependent variables. We called ESP-ISA to the contextualized adaptation in the Spanish educational system of the evaluation test used in the International Schools’ Assessment program (ISA), designed and implemented by the Australian Council for Educational Research (ACER) in 2001. These tests have educational and psychometric contrasting features and the students’ results are expressed on a scale that allows for comparison with the scale used in the PISA study.

CORDERO, J.M., CRESPO, E. & PEDRAJA, F. (In press) Rendimiento educativo y determinantes según PISA: Una revisión de la literatura en España. Revista de Educación, 362 GAVIRIA, J.L. & CASTRO, M. (2005) Modelos jerárquicos lineales. Madrid: La Muralla. LÓPEZ, E., NAVARRO, E., ORDOÑEZ, X. & ROMERO, S.J. (2009). Estudio de variables determinantes de eficiencia a través de los modelos jerárquicos lineales en la evaluación PISA 2006: el caso de España. Archivos Analíticos de Políticas Educativas, 17, 1-27. OCDE (2009). PISA 2006: Data analysis manual. SPSS users. Paris: Organisation for Economic Cooperation and Development. OCDE (2010) PISA 2009 Results: What Students Know and Can Do, Paris: Organisation for Economic Co-operation and Development RENDÓN, S. & NAVARRO, E. (2007). Estudio sobre el rendimiento en matemáticas en España a partir de los datos del informe pisa 2003. Un modelo jerárquico de dos niveles. Revista Electrónica Iberoamericana sobre Calidad, Eficacia y Cambio en Educación, 5(3), 1-19.