Are graders biased?

MICHAELDIXON

If "John" has a preference for blast white coins, do you think he grades original skinned, toned coins lower than he would blast white ones? And likewise, if "Tom" has a preference for original skinned, toned coins, do you think he grades blast white coins lower than toned ones? Would either give a boost for their preference?

kranky

Well, as the process is subjective by its very nature, it wouldn't surprise me if there was a TENDENCY towards bias. But I expect the TPGs to adequately train their graders so there is consistency. So while Tom may greatly prefer original skin, he needs to be sure he does not bump up eye appeal beyond what the TPGs standard is. I'm OK with graders having a preference from a personal point of view, but they have to keep that preference from affecting their grades.

kryptonitecomics

I think that is very likely the case no matter how good their intentions are to be fair an impartial. I think the clearest proof of that relates to NGC's star designation....... beauty can certainly be subjective but I have seen some absolutely hideous coins with stars and some stunning neon colorful beauties with booming luster without stars??

coinguy1

Speaking as a former grader, my answer is that everyone is biased (either consciously or not), in one way or another. But that graders make efforts to overcome any bias that they are aware of.

If a particular bias is strong, it should eventually become obvious to the other graders and efforts can be made to "correct" it.

As a couple of examples, typically, I am not overly concerned with a coin's strike, unless it is noticeably weak. I had to learn to place a bit more emphasis on strike. On the other hand, I had a tendancy to "micro-grade" - to place too much emphasis on tiny flaws, while not giving enough credit for other positive compensating factors.

Fairlaneman

I think the only bias is the amount of the grade that reflects toward the amount of luster that is showing. You can have a technically very nice coin that has somewhat muted luster because of its original skin getting a grade that sometimes is 2 points below its true and actual grade. Its almost seems like the graders want you to dip a coin to bring out the luster. This refers to mercs only but maybe other series are the same also.

And Yes Mark sometimes you do micro grade. A 29S merc you looked at years ago comes to mind.

Ken

notwilight

To oversimplify what Mark said well, graders are human. --Jerry

TomB

<< <i>If "John" has a preference for blast white coins, do you think he grades original skinned, toned coins lower than he would blast white ones? And likewise, if "Tom" has a preference for original skinned, toned coins, do you think he grades blast white coins lower than toned ones? Would either give a boost for their preference? >>



I'm glad that Tom likes the original skinned, toned coins!

Unknown

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coinguy1

<< <i>

<< <i>Speaking as a former grader, my answer is that everyone is biased (either consciously or not), in one way or another. But that graders make efforts to overcome any bias that they are aware of.

If a particular bias is strong, it should eventually become obvious to the other graders and efforts can be made to "correct" it.

As a couple of examples, typically, I am not overly concerned with a coin's strike, unless it is noticeably weak. I had to learn to place a bit more emphasis on strike. On the other hand, I had a tendancy to "micro-grade" - to place too much emphasis on tiny flaws, while not giving enough credit for other positive compensating factors. >>



I wish I could find all the coins Mark graded whilst working for the TPG, they would all be way undergraded >>

Alan, I know you were (mostly) kidding, but remember, I was providing just one opinion and was not a finalizer.

Teva

I think that is why they have three different graders grade your coins. Grading is a process not just a opinion and our host is very open about that process. I think that most collectors/dealers over grade there coins so its hard to blame toning for a grade that you may or may not agree with.

chumley

all right handers are biased...but we learn to cope with them

atarian

<< <i> I had a tendancy to "micro-grade" - to place too much emphasis on tiny flaws, while not giving enough credit for other positive compensating factors. >>



I do this now with buying coins period . I usually grade a coin down 1 grade due to these flaws, especially with coins I dont usually collect or deal with on a regular basis

ColonelJessup

I don't see "preference - predisposition - bias" being an issue. I take inference from "bias" that something is seen to be "off" and you want to call attention to it. Perhaps I'm reading too much into this.

All graders react differently to various attributes like marks, depth and location of same, brightness, color, and eye-appeal. Are they brutalizing dull coins or valuing brightness? Etc, etc. The nicer the coin, the more you find people agreeing.

Variations are everywhere. TPGs use consensus grading from great graders with millions of images in their heads both individual and blended. The pattern recognition wetware is in place.

More reliable/predictable, nothing like precise.

fivecents

Grading is subjective be you professional or just a rookie.

ricko

Grading may indeed be a process... but it is, and as long as humans do it, it will always be an OPINION!!! Yes, a skilled opinion, but nonetheless, an opinion. Cheers, RickO

tahoe98

...ditto ricko.

Mission16

Yes.

kurtdog

<< <i>If "John" has a preference for blast white coins, do you think he grades original skinned, toned coins lower than he would blast white ones? And likewise, if "Tom" has a preference for original skinned, toned coins, do you think he grades blast white coins lower than toned ones? Would either give a boost for their preference? >>

I think their challenge is to remain as unbiased as they can. That's their goal, anyway. In fact, as a commercial, third-party grader, that's really their only utility. They're here, in other words, only because of the existence of bias, and to hopefully eradicate, or, at least, reduce same. That bias, of course, would be the natural bias of the seller to grade high and the buyer to grade low.

blueifalcon

But it must drive experienced numismatists crazy when their coins are returned with a lower grade than they expected. So, I'll ditto ricko on the opinion comment.