11 Plus Exams Forum

Just wondering whether anyone could offer an explanation as to why some 11+ books and test papers listed on Amazon have rather silly price tags. This seems to be the case primarily with the out-of-print titles, so I understand they are difficult to get hold of, but seriously, would anyone really pay over £900 for a small book of comprehension exercises or near £370 for a set of maths tests? Am I missing something?

I'm assuming that they're people who have a lot of books for sale and let Amazon automatically set and manage the prices (which I agree seems to result in some crazy pricing).

Thank you, that makes sense. Yes, the sellers seem to be second-hand book traders, so likely to have quite a few books for sale. It seems a very sensible thing to have someone else look after the pricing but whatever the algorithm that Amazon uses to do that, it's a bit odd.

Maybe some of them are just missing a decimal point? Or the seller is only willing to part with the treasured item if it pays for a bucket list experience? Who knows...

Stroller wrote:Maybe some of them are just missing a decimal point? Or the seller is only willing to part with the treasured item if it pays for a bucket list experience? Who knows...

I did think about the decimal point, but it's usually not missing, e.g. a price may be £367.24, so maybe it is in a wrong place.... There are various sellers with very high-priced items on Amazon and they seem to be mainly business sellers. Maybe they are businesses with expensive bucket list wishes?

I know this one... It's simply a pricing bot algorithm.
Sellers can auto-set their pricing so that their "vgc" book is priced at e.g. 50p above the lowest price book", theory being that the buyer will pay 50p more for their better copy.
Then it's all fine.....unless the other buyer has set their price as "£1 above the Lowest other price" (on the grounds that when two people want to buy the book, theirs will make more). So you get two book priciing systems looking at each other, both looking to increase the price a bit.

So you have three copies of a book: one (non botted) is for 0.01 plus postage.
someone buys the book that's 0.01 plus 2.80 postage.
This leaves our two remaining copies at 0.51 and 1.01. The 51p book then looks at the 1.01 and its bot thinks "ok, I need to be 50p above that one" and increases its price to 1.51.
The 1.01 book then says "ooh, it's gone up! Must be demand. I'll increase again... To 2.51."
The bots then "fake bid" against each other until either someone buys the lower price copy (which may be when it hits almost the new price) or one seller notices the silly price and withdraws it, leaving the other copy stranded at £253.17 for some nursery rhymes.

Could try contacting the seller of the terribly expensive books and make an offer. They may not realise what the price bot has been up to

Aethel wrote:I know this one... It's simply a pricing bot algorithm.
Sellers can auto-set their pricing so that their "vgc" book is priced at e.g. 50p above the lowest price book", theory being that the buyer will pay 50p more for their better copy.
Then it's all fine.....unless the other buyer has set their price as "£1 above the Lowest other price" (on the grounds that when two people want to buy the book, theirs will make more). So you get two book priciing systems looking at each other, both looking to increase the price a bit.

So you have three copies of a book: one (non botted) is for 0.01 plus postage.
someone buys the book that's 0.01 plus 2.80 postage.
This leaves our two remaining copies at 0.51 and 1.01. The 51p book then looks at the 1.01 and its bot thinks "ok, I need to be 50p above that one" and increases its price to 1.51.
The 1.01 book then says "ooh, it's gone up! Must be demand. I'll increase again... To 2.51."
The bots then "fake bid" against each other until either someone buys the lower price copy (which may be when it hits almost the new price) or one seller notices the silly price and withdraws it, leaving the other copy stranded at £253.17 for some nursery rhymes.

Aethel, that's a brilliant explanation . I knew that somewhere in the murky recesses of my brain, I also understood what must be happening here, but even a strong cup of coffee and a long-handled broom were unable to unearth the knowledge . I shall now file your explanation somewhere - perhaps not 'safe', though.

Aethel wrote:I know this one... It's simply a pricing bot algorithm.

Thank you for explaining this so well, Aethel, now I understand!

That's ok, purpleduck, it was explained to me by a clever friend with a maths and computing degree a while ago!