Knowledgebase: Feedback
SCOTLAND:A pupil with a high MidYIS score is predicted around C/B in a Scottish National subject, but the corresponding chances graph shows that grade A is most likely, followed by B, then by C, and so on. Why is there such a discrepancy between the two?
Posted by on 25 February 2013 11:52 AM

Although they may appear at face value to be very different, in fact the chances graph and the prediction of C/B are consistent with each other. The prediction of C/B comes from a regression line, and regression lines provide estimates of what happens on average for a given MidYIS score. In the case of a pupil like this, although the A grade has the highest probability, the average grade has to be less than A because the pupil cannot do better than A, but can do worse and could do substantially worse. It is the probabilities of the pupil achieving grade B, C, D and N4, grades all lower than A, that explain why the predicted grade is only C/B.


Comments (0)