A decentralized anonymous marketplace • Hacker News Board

Re: A decentralized anonymous marketplace

#41

Post by DennisP » Tue, Mar 25, 2014, 1:24 PM UTC

runeks wrote: post #16

hendzen wrote: post #15

Earlier quoted context omitted.

You can use proof-of-sacrifice to give reviews a cost. Look up OP_RETURN in relation to bitcoin.

Without having thought about it further, this might work. All we would need to do would be to "burn" a certain percentage of the transaction, eg. by sending it to an provably unspendable address (a hash160 of all zeros, for example). So the transaction from the customer to the vendor, paying for the goods, would be a 2-of-3 multi-signature transaction (of which the customer, the vendor and the escrow agent each hold…

Might also help if the burn amount could be denoted as positive or negative. If zero is the worst, it might just mean "didn't care." If someone spends a significant sum on a negative rating, you know he was pissed.

There have been some behavioral economics experiments showing that people are quite willing to make sacrifices to punish offenders.

Re: A decentralized anonymous marketplace

#42

Post by chirau » Tue, Mar 25, 2014, 1:41 PM UTC

runeks wrote: post #14

As far as I can see, the essential problem with decentralized anonymous marketplaces is that reviews need to cost money. Plain and simple. Good reviews have great value, so they need to have a non-zero price. A vendor's review history is the indicator by which you assess whether a vendor is trustworthy or not, and a vendor should have to pay to achieve a trustworthy reputation - if good reviews are free, and you can…

What about creating some sort of token which allows a user to review a seller? The token itself can only be generated by a successful and verified transaction. One transaction would equal one token which would allow only one review to only that specific seller.

Re: A decentralized anonymous marketplace

#43

Post by garrettgrimsley » Tue, Mar 25, 2014, 1:49 PM UTC

chippy wrote: post #21

runeks wrote: post #14

As far as I can see, the essential problem with decentralized anonymous marketplaces is that reviews need to cost money. Plain and simple. Good reviews have great value, so they need to have a non-zero price. A vendor's review history is the indicator by which you assess whether a vendor is trustworthy or not, and a vendor should have to pay to achieve a trustworthy reputation - if good reviews are free, and you can…

Every seller who sells their product is able to review a buyer. It costs them. Every buyer who buys something from a seller can review them. It's part of the cost of the goods. Escrow - same deal. Edits - this does seem too simple. Is it just naive? Perhaps it doesn't exclude circular transactions and gaming it.

Yes, it is too simple. If a vendor wants to pose as a buyer and post fakes reviews if there is no cost to the transaction itself then there is no cost for the vendor to post a fake review.

In Silk Road the cost of producing fake reviews was the commission cost of the sale.

Re: A decentralized anonymous marketplace

#44

Post by treirich » Tue, Mar 25, 2014, 2:01 PM UTC

When I read this proposal I immediately thought that Namecoin could be an asset, being a decentralized DNS. Maybe use a variant of Namecoin on individual 'store' nodes to resolve them to a single (non-ICANN) TLD that can be spidered and displayed by several aggregators.

http://en.wikipedia.org/wiki/Namecoin

Re: A decentralized anonymous marketplace

#45

Post by Thiz » Tue, Mar 25, 2014, 2:08 PM UTC

rk17 wrote: post #35

The advantages of the anonymous marketplace only really apply to people who's work is being suppressed (activists/journalists) or who's work is rightfully being persecuted (criminals). Maybe there's a case to be made that a lot of people do want to know who they're dealing with, besides that the system (algorithm etc.) thinks they're thrust worthy.

In countries like Venezuela, where government is enforcing laws for price control and shops are shutting down everywhere, an anonymous marketplace would be a godsend.

Citizens under totalitarian regimes are the ones who benefit most from crypto currencies, crypto messaging and crypto markets.

Re: A decentralized anonymous marketplace

#46

Post by allworknoplay » Tue, Mar 25, 2014, 2:15 PM UTC

mrfusion wrote: post #39

People are mentioning the need for reviews in such a marketplace. I present one possible solution: > Users pay some fee to leave reviews. the more they pay the more the review is weighted. > Buyers can rate the reviews on how helpful they are. > A small transaction fee is collected from every transaction and distributed to reviewers proportionate to how many votes their each of their reviews has gotten. I imagine thi…

This is incredibly open to abuse by both vendors and their competitors. A rater's "realness" is probably much better judged by other measures of marketplace activity or simply equal weighting than by their willingness to pay to bias the ranking of a particular review. I'd tend to defer to what's worked in other (semi) anonymous markets -- it's pretty easy to tell when someone is real or not based on their activity patterns.

A better policy is probably to keep raw information available and let people parse it in different ways, rather than baking in a risky and probably fragile system we hope will work.

Re: A decentralized anonymous marketplace

#47

Post by allworknoplay » Tue, Mar 25, 2014, 2:17 PM UTC

runeks wrote: post #14

As far as I can see, the essential problem with decentralized anonymous marketplaces is that reviews need to cost money. Plain and simple. Good reviews have great value, so they need to have a non-zero price. A vendor's review history is the indicator by which you assess whether a vendor is trustworthy or not, and a vendor should have to pay to achieve a trustworthy reputation - if good reviews are free, and you can…

When has this ever worked in the real world? I mean, in theory parts of it are nice, but conflating it with the spam problem is probably not accurate; merchants will just pay for positive reviews for themselves and negative ones for competitors. I ask honestly: are there examples where this has worked?

I feel like the much better system is to increase the available information about transaction and/or review volumes associated with a particular account -- that makes it much easier to filter out bullshit, and mimics the way fakes are detected on the rest of the internet.

Re: A decentralized anonymous marketplace

#48

Post by sealthedeal » Tue, Mar 25, 2014, 2:21 PM UTC

chirau wrote: post #42

runeks wrote: post #14

As far as I can see, the essential problem with decentralized anonymous marketplaces is that reviews need to cost money. Plain and simple. Good reviews have great value, so they need to have a non-zero price. A vendor's review history is the indicator by which you assess whether a vendor is trustworthy or not, and a vendor should have to pay to achieve a trustworthy reputation - if good reviews are free, and you can…

What about creating some sort of token which allows a user to review a seller? The token itself can only be generated by a successful and verified transaction. One transaction would equal one token which would allow only one review to only that specific seller.

The seller could still generate fake transactions

Re: A decentralized anonymous marketplace

#49

Post by rk17 » Tue, Mar 25, 2014, 2:36 PM UTC

Thiz wrote: post #45

rk17 wrote: post #35

The advantages of the anonymous marketplace only really apply to people who's work is being suppressed (activists/journalists) or who's work is rightfully being persecuted (criminals). Maybe there's a case to be made that a lot of people do want to know who they're dealing with, besides that the system (algorithm etc.) thinks they're thrust worthy.

In countries like Venezuela, where government is enforcing laws for price control and shops are shutting down everywhere, an anonymous marketplace would be a godsend. Citizens under totalitarian regimes are the ones who benefit most from crypto currencies, crypto messaging and crypto markets.

Yeah, I should have included that example. Just adding that repression on that scale actually merits regime change more than finding a workaround. Although the workaround might be more feasible in most cases. So, it's a good initiative.

Re: A decentralized anonymous marketplace

#50

Post by runeks » Tue, Mar 25, 2014, 2:47 PM UTC

allworknoplay wrote: post #47

runeks wrote: post #14

As far as I can see, the essential problem with decentralized anonymous marketplaces is that reviews need to cost money. Plain and simple. Good reviews have great value, so they need to have a non-zero price. A vendor's review history is the indicator by which you assess whether a vendor is trustworthy or not, and a vendor should have to pay to achieve a trustworthy reputation - if good reviews are free, and you can…

When has this ever worked in the real world? I mean, in theory parts of it are nice, but conflating it with the spam problem is probably not accurate; merchants will just pay for positive reviews for themselves and negative ones for competitors. I ask honestly: are there examples where this has worked? I feel like the much better system is to increase the available information about transaction and/or review volumes…

> When has this ever worked in the real world? I mean, in theory parts of it are nice, but conflating it with the spam problem is probably not accurate; merchants will just pay for positive reviews for themselves and negative ones for competitors. I ask honestly: are there examples where this has worked?

eBay works this way [1], and I believe this is how Silk Road operated as well, although I'm not sure.

Merchants who pay for positive reviews for themselves and negative reviews for others have greater expenses than merchants who refrain from this, and, consequently, are less competitive.

Imagine a market place with hundreds or thousands of vendors (which is the size an established market place will grow to, if not much larger). Let's say the average total sale volume per merchant is $10k (I think that's a low figure). To nudge all your competitors' total review score 10% in the wrong direction you'd have to buy 1,000 * $10,000 * 10% = $1M USD worth of items from them, and leave all of them a 1 star feedback. Does this sound like an economically viable business approach?

Paying for positive reviews for yourself is cheaper than that, but you're still less competitive than the merchants who actually satisfy clients, and don't have to spend funds to increase their own rating score.

I'm not saying you can't combine this approach with something else, that might very well be the best solution. But I do think the best solution will require paying for reviews, in some way or another.

> I feel like the much better system is to increase the available information about transaction and/or review volumes associated with a particular account -- that makes it much easier to filter out bullshit, and mimics the way fakes are detected on the rest of the internet.

I think I would need more details on this approach to understand what you're suggesting. How would you achieve this in a distributed system? And how do you get around the problem of vendors being able to increase their review score for free?

[1] http://pages.ebay.com/help/sell/fees.html#how