Staggering numbers from eBay

coppercoins

Hi...I'm a regular in the US coin forum and am working on a project that requires collection of data from eBay. I just got finished running a search on eBay and parsing the information through an engine I built (I'm a programmer and database developer) and found the following:

Search was for cards in all card categories graded by the following: AGS, BGS, CEX, CTA, KSA, PSG, PGS, PSA, and SGC.

Search conducted was for all items matching the above from 22 January through 25 January - just three days.

Total returned items : 12,100
Total with bids : 7,881
Total ending price : $643,795

Additionally, the highest item number collected was 3656064212 and the lowest was 2776964320. Considering each item listed gets a sequential item number assigned to it (which may not be the case), the number of items listed on eBay in the period covered by items that closed in those three days would come close to 880 million. If eBay collected only 30 cents per listing (we know this is a low-ball number), they gained over $264,000,000 in that period. I don't see how this is logically possible, but that's what the numbers say.

Looks like a strong market with a lot of items changing hands! More will follow as to why I'm doing this later. I just thought this would be pretty neat info to share.

Southsider

I think you err in assuming that the item numbers are issued in order. The first several numbers (5?) of an item refer to the catagory the item is listed in.

coppercoins

I don't think that's true, Southsider.

Item # 2782808438 is a Mickey Mantle card listed in category: Sports > Cards > Baseball-MLB > Singles (1950-59) > Non-Graded
Item # 2782808435 is a pair of roller skates listed in category: Sport > Funsport > Rollschuhe
Item # 2782808431 is a Richard Petty postcard listed in category: Sports > Fan Shop > Racing-NASCAR > Richard Petty

That these all had to do with sports is a chance occurrence, because some of the items in the same area of numbers are on eBay Germany and are for an adding machine and a web banner account.

In fact, none of the 10 items listed between 2782808430 and 2782808439 belong to the same category. My conclusion - the item number has nothing to do with the category the item is listed in.

Working in database development it only makes sense to issue a category number based on selection, but an item number based on chronology alone. The two would be connected in an relational database by assigning 'categoryId' as a foreign key in the 'items' table and linking the two tables together - one with the item information and the other with the category information.

jvineyard

I listed the these two items 1 minute apart last night:

3272407096

2785864117

Both are graded cards, but one is listed in Sports (football card) and one is listed in Collectibles (a non sport card).

The first number obviously means something other than sequential listing.

coppercoins

That's interesting. It means there have to be at least two different submission engines running at the same time issuing item numbers sequentially but in different blocks. That would be a nightmare to program. Thanks for the info!

So, while my theory of item numbers is blown out of the water, the number of items pulled and the ending prices are accurate. Still staggering considering only three days of ending auctions in one major category.

dominak

I remember someone once saying that they are received/loaded in multiple servers. Maybe thats why the jump in numbers?