This is a market inspired by this recent blog post. I am trying to capture the scenario from the section "No, order is not preserved" as closely as possible.

Suppose there’s a conditional prediction market for two coins. After a week of bidding, the markets will close, whichever coin had contracts trading for more money will be flipped and $1 paid to contract-holders for head. The other market is cancelled.

Suppose you’re sure that coin A, has a bias of 60%. If you flip it lots of times, 60% of the flips will be heads. But you’re convinced coin B, is a trick coin. You think there’s a 59% chance it always lands heads, and a 41% chance it always lands tails. You’re just not sure which.

... people might figure out if it’s an always-heads coin or an always-tails coin

There are two markets in this set, representing two different options our hypothetical futarchy could choose. Of the two, only the market with the higher final price will resolve YES or NO. The market with the lower final price will resolve N/A. If both prices are exactly the same (according to the precise prices from the API) I will flip a coin with FairlyRandom to choose one to resolve.

The rules for resolving the markets involve randomness, and are as follows:

24 hours before the market closes, I will ask @FairlyRandom to (publicly) generate a number from 1 to 100. This represents the chance that coin B is an always-heads coin - if the number is 1-59 (59% chance), then B is an always-heads coin and if the number is 60-100 (41% chance) then B is an always-tails coin.

Then, once the market is closed, I will do the following.

• If the A market is to resolve I will ignore the previous number and ask FairlyRandom for another number 1-100. If the number is 1-60 I resolve Coin A to YES, otherwise I resolve it NO. I resolve coin B N/A.

• If the B market is to resolve, I resolve it YES or NO according to whether it is an always-heads coin or not, respectively. I will resolve coin A N/A.