up to now I don't think it's a good idea to make Bitshares a smart contract platform.

one big concern is security, yes smart contract can bring great flexibility, but it also bring risk, we have seen many security events that had happened in Ethereum&EOS, Bitshares is a system focus on Finance, we should be more careful while handling this topic.

yes smart contract is a trend for public blockchain, but that does not means each public chain should become a smart contract platform, smart contract is a big new feature and is not so tightly linked to Bitshares' current competitiveness.   

great idea.

my concern:

what kind of assets can be used as collateral? only BTS or some UIA such as OPEN.BTC, GDEX.EOS also available? anyway in the  cryptocurrency market BTC,ETH, EOS, etc occupy the most share.

margin trading need good liquidity of the collateral, now even BTS/bitUSD is not in satisfactory depth. so I am also considering other forms of bond market:

A borrow 100$ of bitUSD from B, with X interests and Y terms and put 110$ worth of GDEX.EOS to collateral, A can get the collateral back by paying the debt and interests, when the expire time arrive and A does not pay back the debt and interest, the collateral will be sent to B.

this kind of borrowing is widely used in China OTC market, it do not rely on the collateral liquidity in an exchange.

 

Quote from: bitcrab on October 11, 2018, 11:05:43 am

大跌行情，外盘领跌，外盘价低于内盘价。

因为bitUSD溢价基本是靠比较内外盘价格来计算，所以这种情况下，算法认为bitUSD有折价，开始向下调喂价。

于是，要么引起不断爆仓，要么内盘把价格砸下去让算法觉得bitUSD有溢价，保持喂价。

不是说不能接受爆仓或者内盘价格下跌，但问题是，这种情况下通过简单比较内外盘价格来判断溢价是有问题的。

需要发展更好的算法来判断溢价/折价。

没感觉有问题呀。
当出现差价，如果搬砖不能搬平，那么就是存在折价了。

流动性差，搬砖渠道不通畅，价差会存在较长时间。

但价差和bitUSD溢价未必是等价的，虽然内外盘价差较大，但没看到bitCNY/bitUSD汇率有较大波动。

要努力让bitUSD/BTS交易对与外盘联动才行。。。

So, let me summarize my understanding. We basically have three parameters available that we can use
towards fulfilling our optimization criteria:

* settlement price (price feed) - This is the price that is used for margin calls as well as force settlements.
* MSSR - the max premium a shorter needs to pay (from market) in case of margin call
* MCR - The minimum collateral necessary for call positions, if lower -> margin call

Essentially, we can apply a "feedback loop" on all of them, either by "derailing the price feed", tuning MSSR or MCR.
The main motivation for "detailing the price feed" is because the MSSR as well as the MCR are lower bounded by 100.1%
and thus cannot go lower. A "tuning" of the price feed could lead to reduction of the premium beyond what could be
possible by tuning MSSR or MCR.

Now, the question (at least to me) is, where is the "premium" and how can we lower it, best?

I would like to see how well this approach would work:

* Feed: price feed with a fixed 1% offset from the "fair price" (fixed tuning) - this way, we allow bitasset buyers to outcompete margin calls and have margin calls provide liquidity at 1% 'discount'
* MSSR: at 100% if premium >=0%, else (100-premium*penalty)% if premium <0 (feedback) - this way, we cause margin calls to raise the price in case there is a discount - "penalty" would cause the margin call to pay a premium
* MCR: dynamic MCR at     max(130, 170 - 40 * (premium/5%))% (feedback) - this way, we have a MCR of 170% in case of 0% premium which groes if the premium is <0% and shrinks towards 130% (linearily) in case of premium >0%

The only thing that I am not sure about is if this approach may not lead to more and more margin calls piling up at the settlement
price with not incentive provided to sell into them - unless the external "premium" is negative ...

Thoughts?

in my view, although there are 3 parameters, we do not to make each one dynamic. adjusting all 3 will make things very complex.

feed price: let it return to just reflect the "real market price". it also do good for information.

MSSR: I feel it's OK to set it to a fixed value, either 10% or 5%.

MCR: is 130% low enough as a limit? is say 110% better as a limit? is it possible to set 100% as the limit? as we all agree that we should allow independent margin call orders with ratio<100%

Define "hurt"? Debt positions are attached with responsibilities, we can't deny it.

When smartcoin is oversupplied (which is reflected as trading below par value), actually borrowing more will hurt the peg thus we can say it hurts the ecosystem. In this case, in order to encourage people to borrower less, there need to be methods to reduce debt or keep debt at a certain level.
* the original approach is to encourage people to force-settle, in this case, a positive offset does the opposite;
* the BSIP42 approach (as well as a MCR adjustment approach) is to force the least collateralized positions to be margin called

Either way the cost is paid by the debt position owners.

When smartcoin is under-supplied, to maintain the peg, we encourage people to borrow more. In this case, force-settlement doesn't help and thus should be discouraged. People are still possible to buy from market at fair price even if force-settlement is disabled. The offset doesn't really matter here.

when the debt position is in sufficient collateral, a smartcoin holder can forcibly buy the collateral, this is definitely hurting.

maybe this is what is called "responsibility" of debt position owners according to the initial design of BTS, but what had happened is that we have to adjust parameters now and then to avoid hurting debt position owners, and finally we found force settlement do not provide better buying condition to smartcoin holders than just buying in DEX.

in traditional financial systems, I haven't seen that the borrower's collateral can be forcibly "bought" when the collateral is sufficient.

Peter's idea is actually manually setting a MSSR, then dynamically adjusting price feed, so there is a feedback.
Xeroc's MCR-based idea is also dynamically adjusting MCR, so it's also based on feedback.

I am aware of this while replying, I just want to tell this will make things complex, we may need to set MSSR=100% at bear market while increasing it at bull market, the effect is just "make feed price closer to market price".

Just because people do not use force settlement does not mean that the
ability to do so provides value.
IMHO, force settlement (I settle bitCNY for its collateral) is a core
feature that provides a floor to the valuation of bitCNY.

Unless of course, you are talking about the 5% offset. Of course, if it
doesn't effect the value, nor it's liquidity, we could as well get rid
of the offset.

if we now reset force settlement offset of bitCNY to 0, it will greatly increase the chance to hurt the bitCNY creators and the whole system.
I haven't found a solution that can enable smartcoin holders to settle in "fair" price but at the same time do not hurt the debt position owners.

I believe we all agree here now.

There have been some options to deal with individual call positions that
go <100%:

* Take call positions that reach <(100+x)% away from users and give it to
  the issuer - effetively a x% penalty for the shorter.
* Allow traders to bid for the call position to provide additional
  collateral in exchange for pro-rata shares of the debt.

And possibly others.

make sense, I am also considering another possibility: possible to integrate the feature to force settlement: enable smartcoin holders to settle the margin call orders with CR<(100%+x) with added penalty to the debt position owners?

I think we all agree here as well. The disagreement lies in the means
that we use to achieve that goal. So far, BSIP42 meant that the price
feed formula is modified.

However, there has been plenty of discussion also instead of faking
the price feed, to use the margin call ratio as well as the short
squeeze protection ratio to provide a similar solution.

For instance, according to Peter Conrad, the current situation may well
be achieved by using the actualy/fair price feed and a short squeeze
protection ratio of 0%. That would lead to margin calls to execute at
the price feed instead of additional penalty of additional 10%. The only
drawback (that might not be one) is that the short protection ratio
cannot be negative. That means that in case there is a margin call
pending in the books, people that want bitUSD will provide a "premium"
to the market to snatch bitUSD from the margin calls.
If this becomes a problem, the price feed could still be "modified", but
at all other times, the price feed would reflect the fair price.

please do not call the current feed price as "faking price feed", BSIP42 just redefined this parameter, if it is confusing to still call it "feed price", I think we can rename it to "guide price" and show in the UI.

just setting MSSR=100% will not get the same result as current setting, as there is no "negative feedback" logic inside.

Thanks @xeroc, I great appreciate your efforts to find the consensus.

Quote from: bitcrab on October 01, 2018, 06:31:22 pm

First, let’s define the vision of smartcoin,  in my view, it is 1. enough accurate pegging and 2. enough liquidity. based on these smartcoin will seek wildly adoption comparing to USDT.

I think this is already where people may have a different vision.
For me (and others) the core value proposition of bitassets was:
* always fully collateralized
* settlement available to obtain collateral at a "fair" price.

With respect to settlement, the community has already moved from a
settlement at parity 1:1 with the introduction of the settlement
offset to incentivize shorters to increase liquidity.

My feeling is that those optimization criteria (tight pegging & liquidity
vs. backing and settlement) may not work out together, at least not in
the short term.

So I think we have some difference in defining smartcoin.

In my idea, smartcoin is one solution of the “stable coin” concept which are discussed a lot this year, it is designed as a token that has stable value and is easy to get and transfer when one need it, that’s why I emphasize pegging accuracy and liquidity.

It seems in your idea, smartcoin is more like something that can help people to store value, to hedge the risk in cryptocurrency market.

Let me tell 2 stories.

1.AEX and bigone has listed bitCNY and use bitCNY as the base currency in their exchange, but several months ago they removed bitCNY as base currency because “bitCNY is in serious shortage and very high premium, difficult to get, users are confused and very unsatisfactory”.

2.in August 1971, U.S. President Richard Nixon announced to remove the dollar peg to gold, which had been fixed at $35 an ounce. the Bretton Woods System collapsed.

I’d like to say, before we discussed BSIP42, bitCNY is at a similar dilemma as USD in 1971 - the supply of gold is limited, but the demand to USD increased rapidly, a big conflict comes and US cannot maintain the $35 an ounce gold price.

bitCNY(surely also bitUSD and bitEUR) is potential to get widely adopted, but before BSIP42 the supply of biCNY depend on the price of BTS, that’s why each time bear market comes, bitCNY was squeezed out quickly and lead to very serious shortage and very high premium, at the same time, continuous margin calling bring many users to nightmare.

Maybe in initial design smartcoin is more like just one asset to store value and hedge risk. But if we hope smart coin be widely used in many CEXs as base currency, and in international payments, we have to review and update the design to guarantee the pegging accuracy and liquidity, otherwise smart coins can only  be used by a small community and have no chance to let the whole world share the great innovation of Bitshares community.

force settlement enable smart coin holders to forcibly buy BTS from debt position owners, so here price play a key role, now we set forcesettlement offset and quantity limit to protect debt position owners, now in almost all the cases, to directly buy from DEX is a better way for smartcoin holders to get BTS.

bitCNY has a 5% force settlement offset for long time and this does not impact the value of bitCNY, the value of smart coin do not rely that much on force settlement. if we can not guarantee tight peg+liquidity+fair price force settlement, I believe we should give up the last one.

We both agree on bitassets having a supply side problem and that
we should allow shorters to easier borrow bitassets. According to
my optimization criteria, I still believe we must not allow bitassets
to become undercollateralized (overall - we may find a way to allow
individual positions to go CR < 1)

I agree it's OK to not allow MCR<1 in the MCR based solution.
I agree that the overall collateral ratio need to be >1, the problem is, how to handle some single margin call orders with CR<1? I think it's bad to let these single orders trigger global settlement process. can we just leave these orders there and wait they be eaten or disappear?

Quote from: bitcrab on October 01, 2018, 06:31:22 pm

After BSIP applied to bitUSD the premium fell drastically, we hope we can keep this trend continue until to a close to 0 premium.

Well, arguable, that is expected behavior because we are "forcing" the marketing
to trade according to parity, we do not provide incentive for the market to
move to parity on its own. This difference is what does sit well with the Western
community.

I believe there are incentive - actually the “negative feedback” make this logic appears: if there are demands on smart coins (premium>0), there will be incentive to borrow smart coins and buy BTS, this is true incentive that we had ignored, it means if we can make more demands on smartcoins, we can help the BTS price to go up.

@Jerry, how about the both of us come to a compromise in that we allow the witnesses
to decide how to go forward and whether or not they want to run BSIP42 on bitUSD, or
not. I think, as a proxy, we shouldn't threaten them with the removal of our votes
just because they support(or not support) a BSIP that actually gives the freedom of
choice to them (the witnesses). With that said, I will retract my statement of removing
votes from BSIP2-bitUSD witnesses and would like to keep rational and
constructive discussion like this one going.

at this moment I'd like to stop "threatening" witnesses - frankly speaking I don't think this can be called "threaten", this is just to express opinion of a voter, it's always not easy to push such kind of update, so sometimes voting power is needed, I don't promise to give up the right of a proxy.