Overview of Our Methodology
At PriceCharting.com, our goal is to track the market price of all video games over time. We collect sold listing data from eBay and our own video game Marketplace and run this info through our proprietary algorithm to calculate the current market price.
How We Combine Sales Data to Determine Price
We combine multiple "estimators" to determine the current market price. "Estimators" include methods like most recent sale price, median price, average price, age weighted average price, mean of hinges, and many more.
All of these "estimators" are combined to calculate a very accurate, current market price.
Loose, Complete, New, and Graded Prices
We show prices for products in Loose, Complete (CIB), New, and Graded conditions. In order to determine the condition we look at the title and description for the listing.
- Graded always brand new and sealed, but it's condition has also been graded by a game grading authority like VGA.
- New always means brand new, still sealed in the original box. If a listing contains words like "New", "Sealed", or other similar words we classify it as "New".
- Complete means the item comes with the original box and manual. If the listing contains words like "Complete", "CIB", "Item, Box, and Manual", or other similar word patterns we classify it as "Complete".
- Loose means the item does not include the original box and/or manual. If the lising contains words like "loose", "game only", "disc only" or other similar words in the title or description. "Loose" also includes all listings where we cannot determine the condition based upon the title. "Loose" is the default because often times that is what the listing includes if more descriptive words are not in the title. And loose is our lowest condition rating.
If you do see a listing classified incorrectly please click the 'report' link next to the listing and we will manually review it.
Shipping Costs Are Not Included
The prices shown do not include shipping costs or any other transaction related costs. The price shown is the price people are paying for the products themselves. You can read more about why shipping costs are not included on our blog.
Removing Bad Sales Data & Flagged Listings
Our prices are based upon actual sales data but sometimes sales are listed or classified incorrectly. We have two ways to combat this:
Automated Language Model: We have tools in place to automatically remove "junk" listings.
These are things like selling a Famicom game as an NTSC game, listing game lots as individual games, or selling
Our bots now recognize certain keywords as "junk" and automatically remove them. Words like "Famicom", "Reproduction", and "Broken" are examples of junk keywords but we use many more.
We automatically remove thousands of junk listings every day.
Automated Outlier Detection: Tools are setup to automatically flag listings with abnormally high or low prices.
These are flagged for review by admin to determine if they should be removed or if they are legitimate sales.
We manually review hundreds of listings every day.
User Review: Some listings are very difficult for a computer to recognize as junk. For example
the auction title says nothing about the box and manual being included, but the photo shows the game is complete.
We rely on users flagging those listings by clicking the "Report" link next to them. Clicking that link flags the listing for manual review. Admin then look at the listing and decide if it needs to be removed, reclassified, or left as is.
If you notice listing that is misclassified, please click the "Report" link. It will improve the prices for everyone.
The flag feature is only available for 90 days after the listing ends. At that point eBay removes the listing from their site so we can no longer verify the information.