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by Retric 4090 days ago
Consider, some groups are more willing to guess when given incomplete information and the SAT promotes guessing. If there was a larger penalty for wrong answers other groups would do better. Another issue is retaking the SAT tends to increase scores as you keep your best individual score.

Individually adding ~30 points might mean little, but when you look at large groups of people such small changes become important.

2 comments

I don't see what's wrong with the guessing mechanism.

If you cannot eliminate any answers, then your average expected score gain will be the same as not answering.

If you can eliminate choices, then your average expected score gain will be proportional to how many answers you've eliminated.

If a group fails to realize this I would say the SAT was successfully in measuring their cognitive abilities in this regard.

is the SAT about [whatever it's testing], or is it about how good you are at estimating your confidence in your partial-guesses?
The penalty is designed so that you will not gain more points than you deserve if you guess and had no idea which answers were wrong.

If there are 5 choices and you randomly guess, you have 4/5 chances to get -1/4 and 1/5 chance to get 1 point. That means if you had no idea which answer is correct, you will net 0 points over the long run, and this will be the same as leaving the question blank. 4/5 * -1/4 + 1/5 = 0.

If you are able to eliminate 1 choice, you will on average get 1/4th more points by picking a random answer among the remaining choices. If you are able to do that, then you deserve the extra points, because it took more knowledge for you to eliminate it.

Anyone that doesn't realize this deserves to have a lower score, and if you can't eliminate answers then you also deserve a lower score. Bringing in racial and gender biases into this is ridiculous.

It's a completly arbitrary choice that happens to benifit white males. Of course people are going to bring up racial and gender bias issues.
I just showed you it wasn't an arbitrary choice and that it has a mathematical basis.

Someone who has the ability to eliminate at least 1 choice understands the question better than someone who doesn't know what the question is asking at all, and is appropriately rewarded for it.

If they removed the penalty and automatically guessed for questions left blank that would have the same effect mathematically, but women would score better. (AKA blank questions would be worth (1/number of choices) on average and educated guessing would improve your score on average.)

So, it is an arbitrary choice.

is there any evidence for this theory or did you just make it up?
From a quick google:

"We find that when no penalty is assessed for a wrong answer, all test-takers answer every question. But, when there is a small penalty for wrong answers and the task is explicitly framed as an SAT, women answer significantly fewer questions than men."

http://freakonomics.com/2011/11/18/sat-strategy-by-gender-me...

Retaking the test: http://philvol.sanford.duke.edu/documents/SAN01-20.pdf

PS: Making an unbiased test is really hard, the SAT comes reasonably it’s not there.