Annex A4

This annex provides technical details for the analysis of variance performed for the language demand section of Chapter 5. In all cases a full factorial ANOVA was performed in SPSS using a univariate GLM procedure. The dependent variable in all cases was defined as item difficulty in logits centered at 0 for each country. The two factors in all cases were the same: country and categorized word count (see Chapter 5 for the detailed description of word-count). In the first case no other factors were added (see Table 5.1), in the subsequent cases one of the 3Cs were added (Tables 5.2 through Table 5.5) as a third factor (context, competency and content in the form of traditional topics). The third factor was added to find whether there are interactions between the word-count and features discussed in Chapter 5. Please note that as in Chapter 5, the content is categorized by traditional topics such as Algebra, Data, Geometry, Measurement, and Number. In addition to the F statistics, that show significance of main effects and interactions, partial ..2 is also provided to assess for the percent of total variance in the dependent variable accounted for by the variance between categories (groups) formed by the independent variable(s).

Learning Mathematics for Life: A Perspective from PISA

Annex A4

Word-Count and the 3 Cs - Analysis of Variance