Skewing of marks in Bucks test
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Skewing of marks in Bucks test
Hi all,
Sadly back on here as DD2 didn’t quite achieve the magic number!
Still deciding on going to selection review or not.
I heard that there is a slightly odd skewing of marks meaning there are fewer kids with scores between 110 and 121. Has anyone else heard that? Why would that be?
Not sure if makes much difference to anything but I’m just curious if someone with more stats nous than me can make sense of that?
Thanks,
Woobywoo
Sadly back on here as DD2 didn’t quite achieve the magic number!
Still deciding on going to selection review or not.
I heard that there is a slightly odd skewing of marks meaning there are fewer kids with scores between 110 and 121. Has anyone else heard that? Why would that be?
Not sure if makes much difference to anything but I’m just curious if someone with more stats nous than me can make sense of that?
Thanks,
Woobywoo
Re: Skewing of marks in Bucks test
Where did you hear this, Woobywoo? I'm not statistician either, but I thought the spread of marks should be the same each year.Woobywoo wrote:Hi all,
Sadly back on here as DD2 didn’t quite achieve the magic number!
Still deciding on going to selection review or not.
I heard that there is a slightly odd skewing of marks meaning there are fewer kids with scores between 110 and 121. Has anyone else heard that? Why would that be?
Not sure if makes much difference to anything but I’m just curious if someone with more stats nous than me can make sense of that?
Thanks,
Woobywoo
scary mum
Re: Skewing of marks in Bucks test
I heard it from a local tutor who said ‘headteachers would know about it’ . Ours didn’t and our school had at least 5 out of 30 children with marks in that range...
Thanks
Thanks
Re: Skewing of marks in Bucks test
Have you seen previous years' spread?
For instance, 2018's looked like this.
Here's 2017.
Here's 2016.
And here's 2015.
Looking at them on a comparison basis, even ignoring the slightly different format each year, there are greater differences in the bell curve than I would have expected to see. Also interesting to see that last year the average score was 112, and previous years it has been 100. That seems odd, although it was the first year with GL.
It may well just be a statistical coincidence given how much variation there seems to be in the "shape" each year. That said, given the controversy over the VR paper and the increased likelihood of appeals, I can see how a theory could develop that they're reducing the amount of children in the likely-to-appeal range. I can't see how they could do that though - children score what they score. I'm no mathematician but while you can adjust the cut-off point for qualification, you can't change the shape, surely? If fewer children have scored in that range (assuming it is true) then it can only be a coincidence. Happy to be corrected though.
For instance, 2018's looked like this.
Here's 2017.
Here's 2016.
And here's 2015.
Looking at them on a comparison basis, even ignoring the slightly different format each year, there are greater differences in the bell curve than I would have expected to see. Also interesting to see that last year the average score was 112, and previous years it has been 100. That seems odd, although it was the first year with GL.
It may well just be a statistical coincidence given how much variation there seems to be in the "shape" each year. That said, given the controversy over the VR paper and the increased likelihood of appeals, I can see how a theory could develop that they're reducing the amount of children in the likely-to-appeal range. I can't see how they could do that though - children score what they score. I'm no mathematician but while you can adjust the cut-off point for qualification, you can't change the shape, surely? If fewer children have scored in that range (assuming it is true) then it can only be a coincidence. Happy to be corrected though.
Re: Skewing of marks in Bucks test
Yes you are probably right Scary Mum.
Sparklies thanks for sharing those graphs here. It really doesn’t make sense to me. On one of the years it seems so obvious from the graph that the average is not 100 - whatever the mathematical interpretation of average one takes.
And 2018 looks like so many more children scored highly. How 112 could be average seems nonsensical to me.
Given the cock up with the VR paper this year I don’t have much faith in how robust this process is.
Sigh.
Thanks both your comments
Woobywoo x
Sparklies thanks for sharing those graphs here. It really doesn’t make sense to me. On one of the years it seems so obvious from the graph that the average is not 100 - whatever the mathematical interpretation of average one takes.
And 2018 looks like so many more children scored highly. How 112 could be average seems nonsensical to me.
Given the cock up with the VR paper this year I don’t have much faith in how robust this process is.
Sigh.
Thanks both your comments
Woobywoo x