Differences between students' PISA reading literacy scores and grading for mother tongue and literature at school : A geostatistical analysis of the Finnish PISA 2009 data

In Finland, the national Core Curriculum for Basic Education defines the learning objectives along with the numerical grade to be given for good competence in each school subject in the final phase of basic education. While serving as a guideline for schools and teachers, it should also ensure an objective evaluation of all students in Finland. In this paper, we take a closer look at the equality of student assessment in Finland in the light of student performance in the Programme for International Student Assessment (PISA) 2009. This study investigates the relationship between the grades given to students in mother tongue and literature at different schools and the same students’ reading literacy performance in PISA 2009. The results are presented as a map produced using a method called kriging (McCoy and Johnston 2001). Kriging is a geostatistical interpolation method based on the statistical relationship among measured points’ spatial autocorrelation. In this case, the method produces contour maps illustrating areal differences for educational variables. The contour maps and related analysis indicate that teachers tend to adjust their grading practices to the general competence level of their class or school rather than strictly following the national curriculum guideline for student assessment. This may lead to local variations in terms of students’ school grades as indices of learning achievement and becomes evident when contrasted with an external, nationwide reference point, such as their reading literacy performance in PISA 2009.