Random walk market, free money, see description, (v2: step size 5)
resolved Apr 2
Resolved as

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.


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.

Get Ṁ200 play money

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Seems reasonable that this bit coin market could be considered analogous to this random walk market, albeit Bitcoin is traded and subject to manipulation by market actors rather than a truly stochastic process. But perhapsfor the layman bitcoin market outsider it might as well be stochastic?

if this market is recreated the reroll should be: roll if 10 people or roll if 3 days

predicted YES

@Redact I think it would be cool if the market automatically progressed on its own at regular intervals but individuals were allowed to add their roll to the market progression under some rules, but it should not require a special audit to tell what the market status should be. So like a trusted automated calculator.

predicted NO

@ShitakiIntaki Interesting. Kind of a merger of the two ideas I’ve been considering for the next iteration, both of which would require custom bots.

My ideas were either a new bot to replace usage of FairlyRandom that did eligibility and sum total calculations for you (and then it would be feasible to do more complicated rules like eg a once a day rule) or a market that updates all by itself at regular intervals.

predicted NO

@ShitakiIntaki Do you have a final count to which to resolve the market?

predicted YES

@YaakovSaxon no change since my last post 13 days ago. R2D2 was the last valid roll, market odds at 65%

predicted YES

@howtodowtle , @SneakyElbow , @JimHays , @A , @HarishGanesan , @Redact , @OrlandoMoreno , @blake , @viluon , @Odoacre , @PeterBerggren , @AndrewHalsell , @Devansh , @NicholasJarrett , @enaz , @Celene , @Lorenzo , @Conflux , @Renz , and @eacc are all eligible for re-rolls.

Interesting quality of a random walk with stopping points, the expected number of steps till resolution is equal to the product of the distance in steps the walk is from each stopping point, so this market started out with an expected 100 (10 x 10) rolls to complete. We are now at 63 valid rolls in and have an expectation of 91 (7 x 13) more rolls to go.....

predicted YES

@YaakovSaxon may consider taking out an ad, or resolving to market; no new rolls in over a week.

bought Ṁ0 of NO

This market should probably be added to the market description, since it has a conversation and references to mathematics supporting the premise that the probability of a random walk on the interval of 0 to 1, where 0 and 1 are stopping points, resolving to 1 is equal to the current position of that random walk. i.e. if the position of the random walk is 0.5 then the probability that the random walk will reach 1 before reaching 0 is 50%.

@R2D2 your random number is: 0

Salt: umBswU19th1jLgnBfgvq, round: 2791082 (signature aa40320c209a88753f071e903ce5a63d8777cd9fa35582a0baa971722692ac9adce80f8bb509923c53528169e4b034a10ccbac5d9703c0fb0ce7b53b3f66ba18214867dec3994e0626d42c55344ad77764176681203902df0bc8a9b99c86b109)

predicted YES

@Redact is the most recent user to become eligible to re-roll

@R2D2 you asked for a random integer between 0 and 1, inclusive. Coming up shortly!

Source: GitHub, previous round: 2791080 (latest), offset: 2, selected round: 2791082, salt: umBswU19th1jLgnBfgvq.

predicted YES

Today I learned you can look at the market in terms of profit rather than shares. Although I am not sure why there seems to be a discrepancy between what the positions sorted by profit reports vs what my summary according to average cost accounting reports.

predicted YES

Just living one roll away between profit and loss.

predicted NO

@FairlyRandom min=0 max=1

@MartinModrak your random number is: 1

Salt: 0WC6umFRYxxA0u8i4GKd, round: 2791068 (signature 94f4a99bc9c2262475699d1c0108208b8b5a11481a21c320443dcaebb482d0f353bddd76f11c7fb744104af4a05c995c15ae05d866ffc1c45140cbc657583f814b43f1c215acc094c70a182b08373fc5d308f6915e013775f19be7987984a9ba)

predicted YES

@Renz is the most recent user to become eligible for re-roll.

@MartinModrak you asked for a random integer between 0 and 1, inclusive. Coming up shortly!

Source: GitHub, previous round: 2791066 (latest), offset: 2, selected round: 2791068, salt: 0WC6umFRYxxA0u8i4GKd.

predicted NO

@FairlyRandom min=0 max=1

@prigoryan your random number is: 0

Salt: HOI8yEXrvhr09ujufFIS, round: 2789810 (signature 83734f8a4649d07c2caa48e9a7f80e103c46c0074aa0d8b5d477b37067443a545cefa7cb4350e150a424d4d1b6c311a20b50fecd2530181e757556696e20b7ad464cbd29eb41da6fa7db82cfb219026db8f5853bf3d5e02d18c551092b8d26db)

predicted YES

@R2D2 is now the most recent user to be come eligible for a reroll.

predicted NO

@ShitakiIntaki Let's reroll then! BTW, is this your profile pic?


predicted YES

@R2D2 You found "me." I thought it was such a cool thing to exist out there in the world.

predicted NO

@ShitakiIntaki It's really cool! Have you been there?

predicted YES

@R2D2 No, I have not. I have done very limited traveling but this would certainly be on my list of places to visit.

bought Ṁ67 of NO

@ShitakiIntaki btw, I got a 0 on my reroll and the market was 70%, do I corrected it down to 65% (5% steps) by buying more NO shares. Was this the mathematically correct (in expectation) thing to do? I don't understand much about random walks, but I'm following the min-tutorial you gave me some time ago 🙂

predicted YES

@R2D2 Yep. You did right by your self and should have a positive expectation for adjusting the market down 5%, from 70% to 65%. I also am trying to post a new audit with each roll to help people returning to navigate this rather robust comments section.