How acceptable is it to buy mana to influence a market on portfolio value?
How acceptable is it to buy mana to influence a market on portfolio value?
13
290Ṁ244
resolved Jan 15
Resolved as
85%

Consider this hypothetical scenario: Say there is a prediction market "Will Alice's portfolio value be at least M$10,000 at the end of January?" Say Alice currently has M$5,000, so Alice buys YES on the prediction market and also purchases M$5,000 worth of mana to get the market to resolve YES.

Is this acceptable? Scroll the the bottom of the comments where I have posted a poll - you can vote either YES or NO by liking the appropriate comment. The poll closes at market close (Jan 14). Resolves to the percentage of votes (YES) / (YES + NO) when I check the vote tally shortly after the poll closes. By voting, you agree to vote honestly.

See fine print of the poll mechanism here.

You are also encouraged to discuss your thoughts in the comments.

(If it matters, assume the market in the hypothetical scenario is run by a reliable third party who is guaranteed to resolve correctly.)

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predictedYES 2y

Poll result is 11 YES, 2 NO. Resolves to 11/13 = 85%

predictedYES 2y

I think the case for YES is pretty strong. Anyone want to offer arguments for NO?

predictedYES 2y

I'm particularly interested in why there's a big gap between this one and How acceptable is it to transfer someone mana to influence a market on their portfolio value?39% . What difference do people see? (Or perhaps is it an artifact of polling error, i.e. different people voting in the polls?)

predictedYES 2y

Anyone want to describe why they think it's good or bad?

predictedNO 2y

@jack It's good because it makes my Manifold shares more valuable.

predictedYES 2y

@jack “Good” has a little too much moral connotation for me; I’ll explain why I think it’s “acceptable.”

In short, the space of actions people can take to influence their own portfolio value includes buying mana, and so should be factored into any suppositions about what could happen to portfolio values in the future.

It’s entirely possible there could be a market made that directly or indirectly hangs on a trader’s portfolio value as a deciding factor, with that trader being completely oblivious to that fact. In such a case, I think it’s extremely difficult to argue that that trader buying mana would somehow be “unacceptable” in those circumstances, and yet the participants in the market would do best to factor in that possibility. Awareness of the market only makes the possibility more or leas likely given the market’s resolution criteria - it doesn’t change anything about acceptability of the act on its own.

Now, if the market were made with some kind of written or verbal commitment that the trader in question would expressly not purchase mana during the market window, then I think there’s an argument against acceptable behavior there.

predictedYES 2y

@MattCWilson Calling myself out also that I presently have this market open 😄 So take my opinions with the appropriate amount of salt.

2y

@MattCWilson I agree, broadly. Some markets are designed to help us be better aligned with outside events, and lots of people see that as the function of all markets. However, some markets (most commonly, 'whalebait') in fact help us become better aligned with our expectations of market manipulation. This is very useful, even if it was not the original intent of the site. Even if you are of the opinion that such markets should not, ideally, exist, the fact that they do exist gives us reason to want to explore that space. We need to be well-calibrated on what sorts of markets will become walebait. The fact that people will spend real money to become the whale in a market is part of the the equation under question. When in doubt if they will consider this cheating, you have to ask, not assume.

predictedYES 2y

@Duncan 💯

I also suspect that markets like these will be noticeably less common in prediction market systems that trade in significant sums of real-world currency.

2y

@MattCWilson One would hope.

predictedYES 2y

Yeah, I largely agree, and YES is my own position as well. However, I think there are some plausible counterarguments for NO.

Awareness of the market only makes the possibility more or leas likely given the market’s resolution criteria - it doesn’t change anything about acceptability of the act on its own.

I think intent does matter. There are acts that are generally considered fine on their own, but problematic when done for profit. An example is my other question How acceptable is it to make 10 alt accounts to influence a market on Manifold's DAU?NO - creating 10 alt accounts is entirely acceptable if done for legit reasons (e.g. running helpful bots like FairlyRandom and ArbBot). But it's unacceptable if done for reasons like manipulating the DAU metric for profit.

That said, I still think buying mana is clearly acceptable even when done for a profit motive on a specific market - after all, isn't that the almost the same as the main reason people buy mana (to profit on markets in general)?

2y

Another way to manipulate your portfolio value is to find a guaranteed 100% market with a lot of volume and buy some NO. You'll immediately book a 1000x return on your profit graph...

predictedYES 2y

@Mira Yeah, there are a ton of ways to manipulate it. I chose this one as a more obvious one.

2y

I wonder: how acceptable would it be to make one of these poll-based markets, get all your friends or alts to vote YES so that lots of people buy YES shares, then buy NO shares and all switch your votes to change the outcome at the last moment? (That would be my concern with polls that let you change your vote.)

predictedYES 2y

@EMcNeill See my rules. It would be unacceptable because I said so explicitly. In general polls without such explicit rules, I think it would still be unacceptable, unless the poll was intended in a more fun/less serious way where gaming/memeing the poll was part of the fun.

Also, I don't think switching votes is an important part of the risk. Just flooding the market with dishonest votes would be a simpler way to manipulate the result for a profit.

2y

@jack Fair points!

2y

Vote by liking one of the comments below:

predictedYES 2y

Like this comment for YES (acceptable)

predictedYES 2y

Like this comment for NO (not acceptable)

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