This market will be a random walk. It's underlying true probability will move up and down in steps according to randomness generated in the comment section. You can generate a bit of randomness and then buy/sell to the new value, and always have positive expected value by doing so.

To participate, use the FairlyRandom bot to generate a number 0-1, by making a comment “@FairlyRandom min=0 max=1”. If the bot returns 0, the true probability goes DOWN by the step size, if it returns 1, it goes UP by the step size.

THE STEP SIZE FOR THIS MARKET IS 5

If the underlying true probability ever hits 0, or 100, it will resolve to NO or YES respectively, and no further rolls will matter. (Pay attention to this). Otherwise I will either resolve to the true probability numerically, or use it to generate a YES or NO answer probabilistically.

I have another market at https://manifold.markets/YaakovSaxon/math-proof-question-re-random-walk?r=U2hpdGFraUludGFraQ, concerning the math of this market, which is presently at 98% that my math is correct. See there for further discussion.

You may roll again if 10 people have rolled since the last time you rolled.

Note that this is the second iteration of this market, with the step size reduced to 5, as the first market resolved much faster than I was expecting.