This is a suggestion for a method of rating transactions to be included in the mutual credit module. Adding such a rating system may be a step toward an earlier (expired) feature request for a reciprocity system (http://drupal.org/node/1229818).

We are developing a complementary currency for use in rural Portugal. Having thoroughly worked through our currency design (as most experts suggest should be done), we have determined that building trust among members is one of our most crucial tasks. We have been using the term 'informed trust' to describe the type of trust that develops from systems such as Ebay's, where any potential purchaser can inform him/herself of any other user's overall rating as a seller.

One important element of such an overall rating is the rating of transactions. We note that in the past Ebay allowed ratings by both buyer and seller, but now implements only ratings by the buyer (of the seller). This seems like a sensible simplification.

We have also noted that Ebay buyers invariably rate a transaction as 100% (5 stars) unless something is wrong. There seems little point in obligating a user to give a rating if that's the case; it may be better to place a default value of 100% as the rating of a transaction by the buyer; then if there is any dissatisfaction it can be marked down.

A user's overall rating might be a straight calculation from these buyer transaction ratings or alternatively it could be a more complex calculation involving account balance, transaction promiscuity, etc.

But, however the overall rating is derived, its most important use is by potential buyers when they are browsing goods or services for sale – since this is when they want to know if they can trust the seller. For this reason it should be visible or easily obtained either directly in the offers/wants module or in the user profile.

One important question is when and where the rating is given. Ebay requires it after the transaction is complete (since purchased goods are usually delivered after the payment is made). An alternative, which would be most suitable in our case, would be to rate the transaction at the moment of signing a payment (since with our currency most transactions will be physically complete by the time the payment is made). Any implemented system should be flexible enough to allow both methods.

Comments

flawer’s picture

flawer commented

I feel like having a say in here :p

What about moderated registration, and/or register by invitation + grant from existant user? or even disable payments for "non verified users"..?

I guess all people will check the "it was ok" box when paying others. so could mean nothing in the end.

I believe more in something like the http://sharewiki.org/en/Evil_code for trustings..

or something like a Currency Health Adviser based on different parameters.. which would make this number more important than the ammount of currency, probably...

scass’s picture

scass commented

Sorry about the long time that has elapsed... We've been getting our exchange system off the ground...

What about moderated registration, and/or register by invitation + grant from existant user? or even disable payments for "non verified users"..?

Yes, in our case we do this anyway. But it only helps determine good intention when a member joins; it says nothing about their behaviour after joining.

I guess all people will check the "it was ok" box when paying others. so could mean nothing in the end.

I don't really see it like that. If I take part in a transaction and it doesn't work well, I don't have a particular incentive to mark it as "OK". If members understand the purpose of the question (ie that it is a contribution to the community as a whole) then I think they will answer truthfully – and will hope that others answer truthfully too. This does seem to work on e-bay; people only buy from sellers who are somewhere in the 90s percent and sellers work hard to maintain their 90+% rating.

I believe more in something like the http://sharewiki.org/en/Evil_code for trustings..

I don't follow that. Too programmatical for me...

or something like a Currency Health Adviser based on different parameters.. which would make this number more important than the ammount of currency, probably...

Yes, I agree that the ideal is probably a rather complex calculation based on number and value of sales, number and value of purchases, ratings, and other parameters. But configuring such a system would presumably be a lot of work. We'd be happy with something rather simple at this stage.

I feel that a simple rating field for each transaction would be helpful to us.

Steve