Fig. 6

Note The black diamond represents the confidence interval around the estimated average log odds ratio across educational systems, and the whiskers extending the diamond define the corresponding prediction interval. The gray dashed vertical line is drawn at log(OR) = 0, corresponding to independence between the covariate and the random responder classification. For the estimates per system, see Appendix 1: Fig. 11 and Tables 1 and 2. Language at Home is coded 1 = Always or almost always speak < language of test < at home/0 = Sometimes or never speak < language of test < at home, hence a positive/negative log(OR) indicates that the odds of having been classified as a random responder is higher for students more/less frequently speaking < language of test < at home. Results are reported for six scales in the TIMSS 2015 student questionnaire measuring three types of students’ engagement and attitudes toward Mathematics and Science