What if? Gerber and the CGC Census...

[valiantman]

What if I had the Gerber Scarcity Index coded for every book listed in the CGC Census?

 

What would you guys like to know?

 

[Scrooge]

What I would like to know is:

 

1. Take the books with Guide in Fine with value over $ XX

2. On that subset, find the number of books graded 8.0 and above for a particular issue

3. Compute the correlation between that number and the Scarcity index

4. On the same subset, find the total number of books graded for a particular issue

5. Compute the correlation between that number and the Scarcity index

6. Run a regression (or a logit model because the Scarcity index is discrete) of Scarcity against either of these numbers.

 

I want to check / see if Scarcity when assigned was driven by total number alone or if Gerber had a bias to giving a higher scarcity number for issues rare in HG only

 

Oh and the usual suspects descriptive stats as well, such as assigned Scarcity index by year / publishers / Top 100 OSPG book / decades.

 

Ok, so the first set of work you might not be able to do but you asked what one would like to see...

[valiantman]

Unfortunately, value (guide, market, or otherwise) isn't one of the fields I have.

 

Gerber SI and CGC Census numbers are all there is at this point.

(If anyone's wondering, 19,138 books listed in Gerber Volumes One & Two

have been graded at least once by CGC.)

[Scrooge]

Unfortunately, value (guide, market, or otherwise) isn't one of the fields I have.

 

Gerber SI and CGC Census numbers are all there is at this point.

(If anyone's wondering, 19,138 books listed in Gerber Volumes One & Two

have been graded at least once by CGC.)

 

Yeah I thought so. You should still be able to do everything without the first value filter, at least the correlations?

 

Also, is there a tendency for Gerber to list number 1 issues as more rare than later issues. I don't know if you have an identifier / can create one for last issues and see if those are considered on average more rare.

 

We are also limited here by our lack of information on print-runs for these books because we should be discussing this on a relative basis.

[valiantman]

Here are some numbers along those lines...

 

[action1kid]

only 1 golden age key has a gerber scarcity index of 10..famous funnies series 1

[gozer]

That's pretty interesting ... thanks for posting it.

 

If I'm reading things correctly, the Gerber numbers are

pretty good, yes?

 

Looking at column 1 and 3 for example, for the books that

Gerber calls a 9 there have only been 43 CGC submissions.

And only 13 submissions of Gerber 10s (13 out of half a million

seems pretty rare to me!).

 

The total number of CGC submissions for Gerber 6 through 10

seem to fit pretty well.

 

gozer

---------------

Ah, there's nothing more exciting than science. You get all

the fun of sitting still, being quiet, writing down numbers,

paying attention. Science has it all.

[143ksk]

Am I correct in assuming that most/all the books with SIs of 1 and 2 are SA? and that most/all of the books with SIs above 5 are GA? If so, would it be possible to pull the SA books out of the running so that we can get a better idea of how many low SI GA books have been graded versus how many high SI GA books have. That might give a better idea of the true relative differences between low and high SI GA books.

[valiantman]

Am I correct in assuming that most/all the books with SIs of 1 and 2 are SA? and that most/all of the books with SIs above 5 are GA? If so, would it be possible to pull the SA books out of the running so that we can get a better idea of how many low SI GA books have been graded versus how many high SI GA books have. That might give a better idea of the true relative differences between low and high SI GA books.

 

Yep, what year would you like to be the cutoff for Golden Age? 1955*?

*See below

 

 

[Scrooge]

Here are some numbers along those lines...

 

 

Thank you Greg. Let's see if we agree on the interpretation:

 

1. Nice comforting last column as we see a monotonic decline in Avg. Univ. Submission in higher than VF as well as in the Avg. Univ. grade. It would indicate that the Scarcity index were reflective of HG availability as well as overall "body count." The highly negative correlation is reassuring

 

1Bis. Notice that the relationship is not as clear for the any grade column - probably reflective that rare books get submitted more often than less rare books.

 

2. Notice there is a "strange" blip for SI of 8. It would appear that the differentiation between 7 and 8 should not exist.

 

3. Notice that most resto work is done on rarer books as seen in the 6th column.

[Scrooge]

Deleted to avoid duplication.

[Scrooge]

Thanks for the update Greg. Most of the comments still hold even after the new-cut-off in place. Actually it works better as the correlation coefficient now increases (in absolute value) from the column about ALL submission to the column about VF and above submission revealing Gerber's tilt / bias to the HG books.

[valiantman]

2. Notice there is a "strange" blip for SI of 8. It would appear that the differentiation between 7 and 8 should not exist.

 

I've noticed this as well... no solid reason, but I have a theory.

 

Given that we're talking about "nothing special" books (that is, non-keys)...

A Gerber 8 is likely to be CGC graded "just because it's a Gerber 8".

While the Gerber 7 is not as "highly prized" for its Gerber rating...

and therefore would probably not be CGC graded "just because it's a Gerber 7".

 

To support this... I checked the Overstreet Top 100 Golden Age (plus Top 10 Silver Age)...

 

 

The "Gerber 8 blip" seems to disappear when you focus on the keys.

[valiantman]

only 1 golden age key has a gerber scarcity index of 10..famous funnies series 1

 

Double Action Comics #2 is a key Gerber 10, if you count books from Overstreet's Top 100 list.

[action1kid]

ah, but it is not a key

[Scrooge]

2. Notice there is a "strange" blip for SI of 8. It would appear that the differentiation between 7 and 8 should not exist.

 

I've noticed this as well... no solid reason, but I have a theory.

 

Given that we're talking about "nothing special" books (that is, non-keys)...

A Gerber 8 is likely to be CGC graded "just because it's a Gerber 8".

While the Gerber 7 is not as "highly prized" for its Gerber rating...

and therefore would probably not be CGC graded "just because it's a Gerber 7".

 

To support this... I checked the Overstreet Top 100 Golden Age (plus Top 10 Silver Age)...

 

 

The "Gerber 8 blip" seems to disappear when you focus on the keys.

 

Greg,

 

it's great that you ran the same analysis on a smaller subset of HIGH PRICED books because I didn't want to continue my blip comment in the direction you took without being careful. Here's what I was thinking. Gerber 8's are rare and therefore probably will guide at a higher value and it's that value increase that will generate the increase in submission for them. By taking out the value factor, i.e. concentrating on high-priced books only, we no longer have to worry about the value aspect and indeed 8's are rarer and consequently tend overall to have a lower grade in the census on average.