IB Results 2020: What do Grade Distributions tell us about fairness?

May 2020 IB grade distributions are similar to previous years' distributions and many consider this to be an indication that grading was fair, reliable, and accurate despite the absence of exams. When the IB used an algorithm to amend predicted marks, the result was a distribution similar to past years. But does a nice distribution ensure that everyone gets the "right" score? Watch and find out as we poke around 2020 Math SL results!

Or don't watch and I'll just tell you that the answer is no. Sure it doesn't preclude correct grade assignment but, since there are so many possibilities, it doesn't ensure it either.

Clearly I have to work on my elevator pitch for these videos :-)

Timestamps
0:00 Intro
1:25 The 2020 Math SL distribution
7:00 The math behind the video

The rest of this description contains links for the documents and sites referenced in the video.

My other videos on this topic:

[mikehanke]

thanks for this video, whole ib process is a disappointment this year

[hollygFM]

Can't believe we're still 4.95X10^39140 away from correct. Can you please show the calculation you used? Presumably those predicted to get a 1 only got a 1, 2, 3... and those predicted a 7 may have been lower, but ertainly not a 1 or a 2. So find out what the predicted grades were -similar distribution. And find out what the fifty thousand moderated IA marks were... Because if a student was predicted a 6 and their IA was moderated from an 18 down to a 13, the student should not have kept that 6... And then we need to find out how accurate schools are individually, and were as a whole for Math SL 2014-2019... A lot going on here...