Get to Know RBH: the Get Current Estimate Function

- by Thomas C. McKinney

There are two powerful functions of the Rare Book Transaction History (RBTH) database that you, as a new or longtime member of Rare Book Hub, may not have noticed, so this article is a brief introduction and walkthrough of our Get Current Estimate feature.

Get Current Estimate is our attempt to make synthesizing the results you find searching the Rare Book Transaction History easier. Many records in the RBTH — both contemporary and historical auction records — include a realized price. By selecting relevant items from your results, you can quickly have us do an aggregated value calculation for specific items, including adjusting for inflation and currency, rather than manually doing it yourself.

Any time that you search the Rare Book Transaction History, you’ll notice that every result has a checkbox on the far-left side:

 

If you search with just general keywords, you’ll have more work to do sifting through the various results and only selecting relevant items. However, being too specific can also be a hinderance. I have personally found that by being general with the title (usually just one or two specific words), but very specific with an author’s last name and the year printed, relevant records are easier to find. In writing this article, I also discovered that putting the year printed in the general keyword search does not currently work

In this example, I’ve done an advanced search with “Bevier” for author, “Indians” for title, and 1846-1846 for the year printed. I’m presented with 25 records. These are all relevant records, but many of them are asking prices from dealer catalogs. In trying to establish a valuation based on realized prices at auction, I’m only selecting auction records. There are six, ranging from 1915 to 1999. After checking the selector boxes for these six records, I’m ready to “Get Current Estimate”:

 

An in-screen pop-up window appears:

As someone who studied economics in college, this is a fascinating page. Beyond the first number you see of the Average Current Estimate, we also provide other interesting data. One of these is the Probability of Reappearance at auction. This can be a useful tool when trying to determine rarity, although I would counsel other methods of due diligence as well. We also display every priced record’s adjusted for inflation — with a twist. Normal, economic inflation is calculated using a price index, specifically the Consumer Price Index (CPI). At RBH, we have enough historical and contemporary data that we have created our own Book Auction Price Index. We calculate this by finding the mean price of auctions in our database for each year and comparing them to the current mean price.

There’s one last tidbit worth mentioning. I’ve fielded requests at least a couple times by members requesting a way to convert foreign currencies to American dollars. The Get Current Estimate function also does this. If it’s an older record, it will be an adjusted dollar value. For prices from 2022, it will be a straight currency conversion.

If you have any questions or simply want to discuss this feature (or anything else about Rare Book Hub), you can reach me at tom@rarebookhub.com.