Orv, I considered the points you make and agree with them to a point, but decided against tracking them simply because they add complexity to the process. My justification for each of these decisions is amplified below. I think if I keep it simple, I'm much more likely to stay with it. I don't think exactness is important here, just as long as the measurement method remains the same over time. As long as everyone knows the "rules", they can adjust as they see fit for their own personal needs.

I think the number of bidders (v. the number of bids) might be interesting, but I think that the number of bids also displays a quantifiable interest in a particular piece. If a single bidder is raising his maximum bid several times, it might show that he is interested enough in the piece to repeatedly reconsider his original "limit." I think this might happen more often with highly desirable pieces than with those that show up every day. This is different than the number of bidders, but either might serve as a proxy for the other. I don't think that the extra trouble of counting bidders is worth it, at least not for my intended purpose.

Regarding the shipping costs, I agree that those are material, but they also tend to be relatively constant seller to seller and piece to piece on eBay. Anything over $10 will be accommodated under my plan. I think that the largest potential difference piece-to-piece ($10 imposed maximum v. free shipping) is not that important. Nobody is going to get too excited over a $10 price move either way, imo. Again, as long as the reader understands the criterion, they can allow a $10 shipping charge if they are budgeting to buy a piece. A buyer would need to consider local costs such as sales tax in their buying decision anyway, so this shouldn't be too hard for a reader to deal with, either.

I agree that neither the low numbers nor Bill's signature add materially to the selling price of a piece, except where a variation is involved, such as green water on a New London Ledge, Minot's Ledge or Barnegat. At least not to the extent that a lightning rod or an AP would. A low number or a signature might attract more bidders, but I don't think the difference in price is worth excluding those pieces from the data. Besides, what is a "low number?" … 24? 99? 102? 999? Things start getting sloppy here, data collection wise. I think the value-to-effort ratio doesn't work out favorably here.

Just my opinion, trying to keep it simple.

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-Art

-Art