The Price Tracker is an online cgi or java program. The Price Tracker would, every day, compile a list of online auctions from eBay and other online bidding sites, along with the prices of sale, keeping a database of auction names, starting prices, sale prices, and possibly even users for each auction. The program would then chart the price of an item giving: the current average price, the high price, the low price, the lifetime average price, the rate of the price's change over various periods of time, and it would be able to graph prices over the day, month, year, etc. a' la stock market graphs.

The price tracker would use keyword recognition as a base to determine whether items were indeed the same item. That is, a user would type in one or more keywords, for example if a person were looking for freeze dried dogs they would type in "Freeze dried" and "Dog." The Tracker would also accept negative tracking words -- so if the user wanted to exclude the possibility of tracking "Freeze Dried Dog Food" they would put in the negative keyword "food." This might still exclude certain of the more exotic posts. The second item assurance check would be on price: if there are enough items matching the search the program would look at the price cluster for a small period of time and if there are matches with prices outside the general cluster, they are flagged. These are still reported to the user so the user might tell whether they are indeed what he or she is looking for. If the program sees multiple price clusters for a single search, it will attempt to generate additional keywords and will come up with two seperate answers. For example, If the user typed in just "Freeze Dried Dog" two sets of prices, one for dogs and one for dog food, might come up. The program would look at the entries and see that, for one of the price areas, food is often in the description, while in the other, food is absent. Thus the search would be narrowed and a report would be given on freeze dried dogs and freeze dried dogfood. Likewise, if a user did a search for "car" the program would notice that certain words like, "explorer" and "altima" would have different clustered values.

From these searches and keywords, the program would build a system of definitions and track things by the now user defined categories, for future reference.

The price tracker would be an invaluable tool in the sale and purchase of online goods and would affect how people bought and sold, making it a potentially fairer system.
-- Sand Jack, Dec 22 2001

Freeze Dried Dog ebay results http://search.ebay....ry=freeze+dried+dog
32.00 [thumbwax, Dec 22 2001]

where did we get to with this ? presumably ebay would hate it, but it would be really interesting to track the 'value' of a product through its lifetime (from initial RSP through subsequent versions, discontinuation, non-supported by vendor, etc. etc.) you could then start to predict how different items were likely to hold their value based on their first few months of prices.
-- neilp, Dec 06 2004


For eBay there are now several companies offering eBay price/market research data including stuff like avaerage price by product/keyword. Check out e.g. https://www.terapeak.com/

Also, you can get a simple "average selling price over last 3 weeks" for any item by just going to eBay, clicking Sell, and enter your item name into the "What's it worth?" box.
-- joelpt, Dec 17 2010



random, halfbakery