Bizarre price swings on Amazon Marketplace

June 24, 2020 1:17 AM

Can anyone explain why out-of-print books sometimes roller-coaster so dramatically in price from one day to the next on Amazon Marketplace? I ask because my own book got some unexpected publicity recently, which sent used copies on a wild price ride. Most recently, the book's price there has moved from £3,722.99 to £3,764.99 to unavailable in the space of just four days. There doesn't seem to be any change in supply to explain this. What am I failing to understand?

The book in question is my murder ballads guide, which I was interviewed about on Radiolab's recent Dolly Parton podcast series. Here's what I wrote in April about the resulting price moves:

"One effect of the podcast was to send the handful of used copies held by Amazon Marketplace vendors on a wild price ride. Would-be UK buyers there were asked to pay anywhere from a low of £75 (Jan 22) to an eye-watering high of £1,223.20 (Feb 10), stopping off at every point inbetween. Even on the unlikely assumption that anyone was actually paying those prices, none of their money was ever going to find its way to either me or the book’s publisher, of course, but the dramatic overnight changes were fun to watch for a few weeks. As I write this (April 7), Amazon US and Amazon UK are listing used copies at $43.97 and £124. 99 respectively."

I get that there will always be chancers who post an absurd price on the very slim chance that someone out there will be daft enough to pay it. What I don't understand is the logic-defying way those prices move. In the case of my first example, for instance, the thinking seems to be "Well, it's clearly not shifting at £3,722.99 - let's add another £42 and see if that does the trick".

posted by Paul Slade to Computers & Internet (7 answers total)

generally bot wars, I understand. Two parties who have automated price responses are tracking each other and creating a loop.
posted by frumiousb at 1:22 AM on June 24, 2020 [17 favorites]

And the reason they might be pricing themselves MORE than the other seller - which is counter-intuitive because normally price wars involve sellers undercutting each other - is that the sellers are likely planning on drop-shipping. The idea is that they will price themselves above another seller, then if you order the item from them, they will buy the book from the lower priced seller and have it shipped direct to you. They then make a profit of the difference between what you paid, and what they paid the lower-priced seller. This works if you have a bunch of "normal" sellers who actually have the item in hand to sell (and just set a static selling price), but if no-one actually has a copy of the book and the only sellers are drop-shippers who don't actually have the item in their inventory, you get a feedback loop where the two drop-shipper bots try to price themselves above each other.
posted by EndsOfInvention at 2:19 AM on June 24, 2020 [29 favorites]

If an item goes out of stock indefinitely the seller can either take the listing down or leave it up until they can restock. If people try to order it when it is actually out of stock they become annoyed that they ordered it and will leave bad reviews for the things they do purchase. The easiest way to edit a listing is just to change the price. By jacking the price up above what anyone would ever realistically pay for it they don't face the site telling them to take the dead listing down, or having to deal with telling customers they can't ship after all.

The reason why they don't want to take the listing down is because they get charged for every new listing. They save on fees by leaving it up.

And then of course, the prices quoted now are often due to information about your IP. Two people with different purchasing histories can look up the same item on many sites and get completely different prices. It's in the site's interests to know what the market will bear on the individual level. You'll see that on Amazon items already in your shopping cart will double and triple in price during a longer session of shopping. Once it is in your shopping cart they raise the price to see if they can get you to complete the sale before it goes any higher. If you are a careful methodical shopper with a budget you can't shop on Amazon because they price themselves out of your business.

So it is more than possible that some of the bigger sites have you down as extremely interested in this book and are jacking the prices up to see if your interest is enough to buy it at $4,000... Flexible sucker pricing is one reason why the merchant who is keeping up a listing with no product has to list their price so absurdly high, and yet another reason why the bots get up to laughable prices.
posted by Jane the Brown at 8:39 AM on June 24, 2020 [2 favorites]

You have to look at the sellers. These are all big warehouse operations and/or drop-shippers with (I am fairly sure) automated pricing, and they may or may not all have a copy. You can tell the difference because these listers don't have real descriptions, just some cut&pasted boilerplate with disclaimers that are the same for every book they list.

Real booksellers who take a look at the condition & the rarity of the physical book in front of them don't do this (they also favor round numbers.)

I get that there will always be chancers who post an absurd price on the very slim chance that someone out there will be daft enough to pay it

occasionally, but this isn't what's happening here.
posted by queenofbithynia at 8:47 AM on June 24, 2020

FYI: I saved a link (for humor's sake) to this old story from 2011 about a $23.7 million developmental biology text on flies.
posted by forthright at 9:30 AM on June 24, 2020 [1 favorite]

I had a similar question.
posted by mpark at 5:51 PM on June 24, 2020

Response by poster: Thanks everyone. I'm much clearer now that I was.
posted by Paul Slade at 8:50 AM on June 26, 2020