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by makomk 2117 days ago
In reality, I think this fiasco has more to do with politics than algorithms. One of the big problems is that the alternatives had downsides which were largely glossed over for political reasons - for example the university growth cap isn't just an arbitrary creation, it exists to stop more prestigious universities siphoning off a disproportionate share of students and leaving less prestigious ones in deep trouble and this seems likely to happen now.

Another big problem is that private schools seem to have made more realistic predictions of their students' results than state schools, as demonstrated by the fact that just taking many of their predictions as-is only caused slightly more grade inflation than in the state school results where 40% were downgraded - and this was portrayed in the press as proof that it was an attack on state schools because their results were disproportionately affected by the algorithmic downgrading.

A third problem is that what it was OK to be concerned about varied depending on which political side it benefitted. For example, there was a completely false and made up claim on social media and in publications that should know better that the Education Secretary had said taking the results would cause students to be promoted into jobs that they weren't competent to do: https://fullfact.org/education/gavin-williamson-fake-quote/ I can't imagine that it would've gone down any better if he claimed students would get onto courses they weren't good enough for, yet a week later after GCSEs went the other way and used predicted results that exact claim was uncritically regurgitated by the media.

5 comments

> Another big problem is that private schools seem to have made more realistic predictions of their students' results than state schools

This might be partially true, but there are also issues in the algorithm that helped cause this skew. For example depending upon the size of the glass the teacher's estimates were adjusted more or less. Very small classes (~8 students IIRC) had no adjustment, small classes (<20 students IIRC) had moderate adjustment, large classes (>= 20 students IIRC) had heavy adjustment. State schools almost never have small classes, while private and public schools (public != state school) were much more likely to fall into the small or very small class size buckets.

>... and this was portrayed in the press as proof that it was an attack on state schools because their results were disproportionately affected by the algorithmic downgrading.

While I won't dispute the point on prediction accuracy, the press complaints were actually about the algorithm itself, which benefited students in a smaller corpus[0]. Typically, only private schools have such small class sizes.

[0]: https://www.bbc.co.uk/news/explainers-53807730

It seems like a classic political no-win situation: if you go with an algorithm then anyone who gets a lower than predicted grade is going to complain (and of course has every right to, as any algorithm is likely to unfairly disadvantage some section of the population). If you give everyone their predicted grades then you're accepting massive grade inflation which makes the grades far less useful as a predictor of a student's ability which then means lots of problems further down the line.
However, the unfairnesses of the two options are very different. On the one hand, you leave it to educators and employers to select candidates based on unreliable grades, versus excluding swathes of the population from opportunity. Leave it to decision-makers that seem to fetishise exam grades and you come to what I'm sure the vast majority of people regard as the wrong conclusion. Yes, there would have been fallout, but so much less toxic had they chosen otherwise.
> On the one hand, you leave it to educators and employers to select candidates based on unreliable grades, versus excluding swathes of the population from opportunity.

That "versus" is unwarranted - unless everyone is given top marks, exclusion happens in either case. In fact it would happen in that case as well, as top colleges (practically by definition of 'top') cannot accept everyone. All you've done is changed who gets excluded, by not adjusting for differing school grading.

> decision-makers that seem to fetishise exam grades

Calling it "fetishizing" is a fine way to suggest there's something wrong with it, without stating what, or how to improve it. Would it be better if, instead of on the basis of grades, students were judged based on who they know, or how much they can donate to the college?

Ofqual Chairman Says It Was A "Fundamental Mistake" To Believe Algorithm Grades "Would Ever Be Acceptable" https://www.politicshome.com/news/article/ofqual-algorithm-m...
"Students will now receive grades based on their teacher’s estimate of what their grade would have been"

But if those estimates are improved using statistics, there's a political fallout. There's some valid criticism of the algorithm used (far less than that BBC article tries to imply), but there's no question the algorithm's estimates were more accurate.

So much ink was spilled calling the algorithm biased for its 4% increase in A-grades for independent schools, yet teacher's 40% increase of grades above the expected average is... what? Unbiased?

On any other topic, such a position would be called "anti-science".

> there's no question the algorithm's estimates were more accurate.

Some people were predicted A's and given U's by the algorithm. It might have been less biased as an average. But it's results were nevertheless completely unacceptable.

There’s a fundamental asymmetry here. Fail a student unfairly, and the harm to them is potentially irreparable. Pass more than usual, and you increase competition for places and while there’s certainly some unfairness there, the system will ultimately compensate through interviewing, delayed starts, etc.
Well, yes. By a curious coincidence he is also chair of the Centre for Data Ethics and Innovation which is publishing a paper on bias in algorithmic decision making.
There is another alternative though: do the damn test. Then everyone gets the grade that they earned.
That assumes that all pupils have had an equal opportunity to study through lock down. I'd speculate that pupils from poorer backgrounds will not have had the same opportunities to study as those from better off backgrounds, so pupils from poorer backgrounds would be disproportionately disadvantaged.
Which is probably true normally to a lesser extent. If you don't have a good place at home to do your homework.
> the university growth cap isn't just an arbitrary creation, it exists to stop more prestigious universities siphoning off a disproportionate share of students and leaving less prestigious ones in deep trouble and this seems likely to happen now.

I've never understood this UK policy personally. In the US there are no such caps and yet less-than-top-tier universities have had no trouble attracting plenty of students. Top tier US universities (e.g. Harvard), with gigantic endowments of tens of billions of dollars in some cases, could easily afford to expand their student bodies two-fold or probably even ten-fold, and yet they don't, despite having no regulations stopping them from doing so. These prestigious universities apparently feel more than enough market pressure not to expand very much, as they feel (rightly or not) that their prestige would take a hit by doing so. I don't understand what the point of creating additional regulatory pressure on top of this would be when e.g. Harvard expanding their student body could easily be a very positive life-changing event for so many students.

In the UK all universities are the same price.
If public schools inflate the marks of the students, why the private students wouldn’t then go to public schools to get better marks?
It's a one off event.

If it weren't then of course private schools might also start giving more generous estimates.

But, also parents might still prefer a better education rather than a higher grade.

FYI public schools are private schools in the UK, the nomenclature is rubbish.