Is a yellis grade reliable?

[eatyourveg]

Just received report for ds3 (Y10) it is in a new format and gives an attainment grade and a yellis grade (except there is no yellis grade for French or PE) There are also scores for homework and effort. He did the yellis in September.

All of the attainment grades are one grade lower than the yellis ones except for 3 which show the same grade in both columns.

Does this mean they don't expect him to progress any further in these 3 subjects? The subjects are English Lit, English Language and Double Science)

Yellis is a predicted grade based on data from a survey. It is very accurate across a population but much less accurate on an individual basis. It is what schools base their targets on. He will do worse in some subjects and better in others. Some students exceed them in all subjects, some students get lower across the board and some are spot on. As a statistician I object to them being out on an individual basis as they are too inaccurate!

Yells is pretty good. It needs every to be set up accurately beforehand so that the students select the correct subjects.

A Yellis grade is a baseline prediction. It is not a target. If a student exceeds the prediction, it means the school has added value.

Thank you both