• The average association between socio-economic background and reading performance is strong, particularly in France, New Zealand, the partner country Bulgaria and the -partner economy Dubai (UAE).
• More than 20% of the variation in reading scores among students in Hungary and the partner countries Bulgaria, Peru and Uruguay is explained by differences in socio--economic background.
• The four top-performing countries in reading show a below-average impact of socio-economic background on students' reading performance.

What it means

In trying to provide students with equitable learning opportunities, education systems aim to reduce the extent to which a student's socio-economic background affects his or her performance in school. Performance differences that are related to student background are evident in every country. But PISA results show that some countries have been more successful than others in mitigating the impact of socio-economic background on students' performance in reading.

Findings

There are two main ways of measuring how closely reading performance is linked to social background. One considers the average gap in performance between students from different socio-economic backgrounds. This gap is greatest in France, New Zealand, the partner country Bulgaria and the partner economy Dubai (UAE), where it is at least 30% wider than the OECD average. In these countries, a student's predicted score is most heavily influenced by his or her socio-economic -background.

While this measure can be used to predict differences in reading scores among students from different backgrounds, many students defy these predictions. Socio-economically advantaged students perform better on average, but a number perform poorly, just as a number of disadvantaged students perform well. To show the extent to which levels of student performance conform to a pattern predicted by socio--economic status, PISA also measures the percentage of variation in reading performance than can be explained by a student's background.

On average across OECD countries, 14% of variation in students' reading performance can be explained by their socio-economic backgrounds. In Hungary and the partner countries Bulgaria, Peru and Uruguay, more than 20% of the variation is so explained. In contrast, in Iceland and the partner country and economies Hong Kong, China; Qatar and Macao, China, less than 7% of the variation in student performance is explained by socio-economic background.

This analysis shows that a student's socio-economic background is associated with his or her reading performance to some extent in all countries. However, in the four countries and economies with the highest reading performance, namely Shanghai, China; Korea; Finland and Hong Kong, China, the link between student background and performance is weaker than on average. This shows that it is possible to achieve the highest -levels of performance while providing students with -relatively equitable learning opportunities.

Definitions

Socio-economic background is measured according to the PISA index of social, cultural and economic status, which is based on information, provided by students, about their parents' education and occupations and their home possessions, such as a desk to use for studying and the number of books in the home. On this index, one "unit" is equivalent to one standard deviation across all OECD students meaning that across all OECD countries, about two-thirds of students are from a socio-economic background that is between one unit above and one unit below the average.

Information on data for Israel: Statlink  http://dx.doi.org/10.1787/888932315602 .