Price Trends of Music/Pro-Audio Equipment on Ebay.

[nathanp]

Alright, let me preface this by saying I don't think that there's a best fit category on Gearslutz for this thread to be posted, but I do think it's something that will definitely be of interest to people on GS.

Anyways, I created a spreadsheet in numbers to track various information about auctions for a given product. I want to see what kind of an impact things have on the final bid amount and net sale price (price + shipping) such as the auction's duration, start price, shipping fee, the amount of other auctions for the same item in progress at the time a given auction ends, Seller feedback score and how many ratings it's based on.

It would be cool if others would like to follow an item or two as well. Then we can post back here in this thread after a month or 2 or however long we keep it going to share data/interesting findings/conclusions/etc.

I tried to make it pretty easy to enter info in the spreadsheet. I did this on Numbers for mac and exported it to excel format cause it seems like way more people use that. I just have a couple formulas set up, to make the gathering of data quicker. You can get a lot of info from a few pages on ebay. If you go to the bid history page you can copy/paste the End date (and time if you wish) and the duration, and the start date will be show up for you. Not that you couldn't do this in your head, but it just makes a tedious process a little quicker.

Anyways, this kinda info could help someone know what kinds of features are indicators that an auction will end at a higher or lower price than average. For example (and this is intuitively obvious), I have noticed a pretty inverse relationship between the final price of an item and the amount of other auctions for the same item in progress at said auctions end time.

Most of this stuff is actually pretty easy to observe and draw conclusions with by intuition, but 1) it would be interesting to tackle this in a statistical manner and see if reality really does reflect what common sense predicts, and 2) a factor that you never thought of as having an impact on an auction could be found to be quite important.

Anyone who downloads the spread, let me know how well the export works in excel. I have a good amount of experience with excel too, and I don't see why it wouldn't be able to make a perfect export, but who knows. I would have made the file with Excel if I had it because then I wouldn't have to worry about exportability, but I went with numbers on my new mac because it's easier and faster for me to use which is a big + since I have to use it a lot in my Biology and chemistry lab courses.