Can trimmed cards in high grades be statistically proven?

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Posted By: Joann

I was just looking again through ebay and a few of the other online auctions. I noticed by how many of the high-end T206's looked small. And it struck me - how often do you see a really big border on some of these high grade cards.

No - just stop folks - this isn't about bashing or to start that whole hoo-ha again. It's an honest question about proving or disproving the issue.

Why couldn't someone measure several hundred, or more, T206's that are lower grade like VGish - measure both t/b and side to side. Then do the same to some high grade slabbed (or not) cards - just anything that would grade a 7 or better, for instance.

Then basic hypothesis testing on the means would give you a certainty that the two samples (VG and 7+) did or did not come from the same population. Because if the higher end cards are trimmed in greater number, the stats should tell you that the difference in size is statistically significant. Or not.

Aside from having access to that many cards, this seems to simple to me. Has it been done?

Joann

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Posted By: boxingcardman

(and yes I know it is lousy grammar)

There are so many thousands of T206s out there that any sample would have to be very large in order to avoid being regarded as anything more than a statistical glitch.

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Posted By: Frank Wakefield

The thing to measure is the size of the image, frame line to frame line.


Think about the old days, a rolling pin in the kitchen, rolling out pie dough...


Some cards have been soaked, rolled and flattened out, soaked again, rolled again, on and on... Then, the card is trimmed back down close to the normal outer dimensions. And there they have a trimmed, doctored card. To me, it is acceptable to soak a T206 to free a piece of a scrapbook, or some tobacco specs. But not for stretching...

So don't just measure the outer dimensions, check out the image.

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Posted By: Frank Evanov

Excellent article on detecting T206 trimming by Dave Foreman in the Feb issue of the SGC magazine. The trick seems to be examination of the edges. This of course cannot be done in a card already slabbed. Size does not seem to matter.

Frank

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Posted By: John S

Actually, a sample size of 20 or above for each grouping (PSA 8 and raw VG's) would be sufficient to test significance. Using a t-test to compare averages (total width of all four borders on each card) between two groups would be the simplest and most powerful test in this case. Set the p-value at .05. Accurate measurements are a must...probably using a caliper of some kind. I believe that a board member has already made these types of measurements...cannot recall who that was.

The t-tests can now be done with most Excel programs.

Nice thought Joann.

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Posted By: Kevin Saucier

<This of course cannot be done in a card already slabbed.>
Sure it can as long as it's not too tight. Even then it is sometimes possible.

Kevin

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Posted By: Richard Masson

but only assuming you can draw a truly random sample. The very act of collecting obliterates randomness.

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Posted By: Frank Wakefield

Hey John, measuring the borders isn't enough... that's the falacy that trips up the grading folks. Gotta measure that box that the image is in.

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Posted By: John S

Frank,

Comparing the measurements of the image area is an excellent idea. I had not considered the stretching issue.

A random sample within the population of T206 cards could be accomplished. It would be a matter of having a pool of cards from numerous collectors and then assigning them a number. The numbers of the cards could then be picked in any unbiased fashion. The measurements on all of the cards should be performed by one individual.

I had mentioned that a sample size of 20 is adequate, but the larger the sample sizes, the more validity a t-test will have. It is not required in a t-test to compare equal sample sizes as it is probably a safe assumption that it will be more difficult to locate PSA 8's than VG cards.

This is an interesting idea but it does not affect me directly. I do not collect high grade material.

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Posted By: boxingcardman

Gonna have to meditate on that one for a while. Sort of a brownian movement theory of collecting.

You know, one thing I've always wondered about this soak and stretch stuff: has anyone here ever actually seen or done it? I hear a lot about it but it seems to me to be science-fiction. I would think that to get the card wet enough and malleable enough to cause it to move enough to make the process worthwhile would wreck the image. So my question is whether any of you have actual firsthand knowledge of this technique.

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Posted By: Kevin Saucier

<has anyone here ever actually seen or done it? I hear a lot about it but it seems to me to be science-fiction. I would think that to get the card wet enough and malleable enough to cause it to move enough to make the process worthwhile would wreck the image. So my question is whether any of you have actual firsthand knowledge of this technique.>


Yes, I have tried it many times, using several different methods, on several different cards. Never had one stretch even a fraction of a millimeter nor have I ever heard of it being done successfully. According to one well known-grader and as expected, it is just another (there are a few) hobby urban legend...but who knows. Of course there will always be someone who knows someone who has done it.

Regardless, in the end, a trimmed card will still look trimmed when examined closely.


Kevin Saucier

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Posted By: Bruce Babcock

I had a card rejected by PSA. A handwritten blurb said "does not meet minimum thickness requirement." I asked what this meant and they said the card had been pressed and trimmed. No mention of soaking was made. I no longer have the flip or the blurb, seeing no reason to keep them, and do not know who I talked with at PSA. This was about 10 years ago.

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Posted By: Glenn

John is right on the sample size issue.

One could also study the relation between surface area and mass of T206s and see if that ratio was higher for high grade cards (suggesting that they are thinner on average than the low grade ones).

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Posted By: Jason L

weigh them!

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Posted By: Rob

Seems like T206's can be trimmed quite readily and not be detected, as compared to T207's and T205's, where trimming would readily show up on those issues. So you can get the PSA population report on these 3 issues and come up with statistical analysis and an argument of a high % of PSA 8 T206's could be trimmed.

On the other, it can be argued that T207's and T205's are graded more harshly with the colored borders, so an argument that a majority of T206's may not be valid.

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Posted By: Eric B

Someone did a caliper test on an earlier thread. But it didn't consider the stretching part. But this is how you can prove the trimming of the PSA 8 Wagner.

It would be very hard to get a random PSA 7 sample. They would have to be new finds or cards with great provenence to eliminate any chance of trimming.

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Posted By: Joann

The process would be to measure cards from the VG and 7+ ranges drawn relatively randomly. Getting samples of 7+ cards that have presumably not been trimmed would defeat the purpose. The intent would be to take any X number - even just 100 - VG card measurements and any X number of 7+ cards measurements and compare them to see if they ARE different, not to try to make sure they are not different in drawing samples.

I think randomness would be kind of easy. I have maybe 20 T206's in VGish shape, and they are probably pretty random - I've gotten them from various sellers over various years, and didn't buy any with attention to overall size.

Similarly, the randomness of the 7+ group would also be fairly easy except for access to these kinds of cards.

Joann