There is other information in here also: The line of best fit through the individual students from this school is more or less parallel to the overall state picture: the achievement of each student has been lifted.
But what of another school?? In this school, while the lower-expectation students have achieved more or less in line with expectation, the higher- expectation students are well above. The slope of the line of best fit is much steeper than is typical. This is described as a +H effect. +H
+H isnt always good news…. This is a +H effect, because the slope of the line of best fit is steeper than typical. However, it is clearly overall achievement-below- expectation. While the higher- expectation students have achieved more or less in line with expectation, the rest of the class has lost it! +H
Similarly, +L can be good news … This is a +L effect, because the slope of the line of best fit is shallower than typical. It looks as though someone has done some great work motivating and/or helping some struggling students. +L
… or bad This is again a +L effect, because the slope of the line of best fit is shallower than typical. In this case, able students who would have been expected to do well have not achieved as well as might have been expected. +L
Using the Second Order Effect for Interpretation +H always means the same as –L: a comparatively steep slope +L always means the same as –H: a comparatively shallow slope You always need to look at a second-order effect in conjunction with the first-order (Primary Analysis) effect It is often interesting to get down to student level: Look at the comparisons between achieved and expected for individual students on Numerical Report 1.
Using Second-Order pedagogically Look for consistent patterns: does a heap of +L show a culture of we have to help these struggling kids? Order your school summary by learning gain, and see if the second-order effects cluster. What does this tell you? The see-saw principle (Where to work next): if we got a +L last year, look for a +H this year.