Two techniques for determining a straight line fit to data are compared. This article reviews two simple techniques for fitting a straight line to a set of data, namely the method of averages and the method of least squares. These methods are compared by showing the results of a simple analysis, together with a number of tests based on randomized…

One of the consistent findings of educational research studies is the effect of the students' family socio-economic background on their learning achievement. Consequently, international comparative studies emphasis the role of socio-economic background for determining learning outcomes. In particular, PISA results have been used to describe how…