Author Topic: review for price feeding  (Read 8169 times)

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Offline Fox

please take good care of your price feeding.

I have identified opportunities for improving my feeds and implemented them for your review:


Please note:: Feeds are updated every 10 minutes and posted to my website:
http://pricefeeds.ryanrfox.com

Newest feed is the top line, older moving down the page.  CER for CNY is 1.2, all others are 1.05

Thank you in advance for refreshing your votes.
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Offline bitcrab

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I've taken a deeper look at price feeds and now i think they are good shape.
Please consider voting @ElMato back to the active witness set.

ok, let's check how it will behave.
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Offline ElMato

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I've taken a deeper look at price feeds and now i think they are good shape.
Please consider voting @ElMato back to the active witness set.

Offline bitcrab

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please take good care of your price feeding.
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Offline bitcrab

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My feeds remain consistently accurate and updated frequently. However, I was recently replaced in the active witness list.

May I request your vote to return to the active witness set? Thank you in advance for your consideration.

voted you, but seems you also need to adjust the algorithm to feed an accurate price.
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Offline Fox


My feeds remain consistently accurate and updated frequently. However, I was recently replaced in the active witness list.

May I request your vote to return to the active witness set? Thank you in advance for your consideration.
Witness: fox

Offline sahkan

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I have adjusted my price feeds and will monitor to make sure the feeds are within small margin of error.

Offline sahkan

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I always try to get the right sources for the price feeds, I will do some manual calculations with weighted averages for volume and will adjust as required.

Offline yvv

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get DEX price A

What is "DEX price A"? Which pair exactly?

it refers to the price in bitCNY/BTS pair in DEX.

You should not use bitCNY/BTS price (not on DEX nor on other exchange) to calculate bitCNY price feed , because it depends on price feed. This is fundamentally wrong, because you trigger a feedback this way, which may be negative (stabilizing) or positive (destabilizing) with equal chance.
« Last Edit: December 24, 2017, 04:21:27 pm by yvv »

Offline bitcrab

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Quote
get DEX price A

What is "DEX price A"? Which pair exactly?

it refers to the price in bitCNY/BTS pair in DEX.
Email:bitcrab@qq.com

Offline yvv

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get DEX price A

What is "DEX price A"? Which pair exactly?

Offline bitcrab

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currently the bitCNY price feeding is far from acceptable.
I will try my best to vote out the witnesses who always feeds a much lower price than the market price.

of course we need to answer one question first: how to define "market price".

regarding CNY market, obviously the market price need to be get first from DEX and also CNY market like AEX.

I don't care how one witness generate the final fed price , but I am sure that a fed price keeping >3% lower or higher than the latest DEX price is not acceptable.

regarding CNY price feeding, one possible algorithm is to get DEX price A and also get price B from other exchanges.

normally just feed A.
if A is 3% or more lower than B, feed B.

this can feed a price that closest to market and avoid the "positive feed back" machanism of DEX price.

take good care of the price feeding, please.
« Last Edit: December 24, 2017, 03:53:49 pm by bitcrab »
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Offline bitcrab

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I think magicwallet can be one reliable source for BTS/CNY price, here an CNY/bitCNY price can be calculated out based on the P2P trading data, combined with the bitCNY/BTS price in DEX, a reliable price can be get.

You shouldn't do that. The CNY/bitCNY price and the bitCNY/BTS price are both influenced by the feed price (and settlement offset). Using these prices to define the feed price creates a feedback loop, which is inherently unstable.

at least it can be one source, I haven't said we need to totally rely on this source.
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Offline pc

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I think magicwallet can be one reliable source for BTS/CNY price, here an CNY/bitCNY price can be calculated out based on the P2P trading data, combined with the bitCNY/BTS price in DEX, a reliable price can be get.

You shouldn't do that. The CNY/bitCNY price and the bitCNY/BTS price are both influenced by the feed price (and settlement offset). Using these prices to define the feed price creates a feedback loop, which is inherently unstable.
Bitcoin - Perspektive oder Risiko? ISBN 978-3-8442-6568-2 http://bitcoin.quisquis.de

Offline bitcrab

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force settlement make sense under current infrastructure, it is the way to claim the value of smartcoins.

however, we need a reasonable force settlement offset, we also need the fed price trace the market price well enough.

if the offset is too low, shorters will be in high risk and will be discouraged to generate smartcoins, supply will be in shortage.

if the offset is too high, smartcoins will be devalued and off-peg.

we need a balance here.

AFAIK, currently BTS price in BTC is firstly got, and then converted to price in USD, and then in CNY.

deviation can happen in each step.

USDT are not equal to USD, this always contribute to the deviation of price.

CNY is not a free convertible currency, the officially published USD/CNY rate are used here but seldom traders can convert CNY to USD in the rate, this is another important factor for the deviation of price, maybe the bitUSD/bitCNY price in DEX is better than the official rate.

all this lead to a result that in DEX the BTS price in bitCNY is 3-5% higher than the settlement price for long time, and lead to endless settle orders.
while endless settle orders appear, it is telling that the system is ill.

to raise the offset to 5% is an urgent action to cure the illness, I don't think it is a permanent solution, we can find from magic wallet that now 1bitCNY = 0.98-0.99CNY, a little off-peg already happen.

so in long term vision the offset should be reduced, maybe not return to 1%, but at least it need to be reduced to about 3%.

surely the precondition is that the price feeding can reflect the market price exactly enough.

I think magicwallet can be one reliable source for BTS/CNY price, here an CNY/bitCNY price can be calculated out based on the P2P trading data, combined with the bitCNY/BTS price in DEX, a reliable price can be get.

this is a chance for magicwallet to contribute to the ecosystem. :)

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在现有框架下,必须承认强清是有意义的,强清是用来实现智能货币对抵押物索取权的。
强清补偿需要足够合理,喂价需要对BTS的市场价格跟踪得足够好。

如果补偿过低,则shorter承担的风险过大,智能货币将会缺乏供应动力。
如果补偿过高,则智能货币对抵押物索取权得不到足够保证,智能货币会贬值,会脱锚。

这里需要平衡。

当前喂价的获得,如果我理解正确的话,应该是先获得BTC价格,转换为USD价格,再转换为CNY价格。

每个环节都可能会带来失真。

转换为USD价格时,因为获得的价格中许多并不是真正的美元价格,而是USDT价格,而USDT价格并不是真正的美元价格,最近这些天,USDT大约相当于98折的USD.

再转换成CNY价格时就又增添了一个因素,那就是CNY/USD并不是自由兑换的,估计许多脚本用的是官方价格,但手持CNY价格的人是无法用官方价格买到美元的,这又是一个失真因素。

也许就是这一切因素导致内盘BTS的CNY价格长期比喂价高5%,催生了持续不断的强清。

持续不断的强清说明系统病了,需要治理。

把强清补偿提高到5%是一种应急措施,是有副作用的,现在根据鼓鼓钱包里反应出的市场情况,bitCNY大约相当于打了99折到98折的人民币,已经有点脱锚了。

所以长期看强清补偿还是应该调低的,未必需要调回到1%,但至少可以调到3%以观后效。

但是,在调低前,需要优化喂价,使其对市场跟踪得足够好。

其实采用鼓鼓钱包承兑数据+内盘BTS/bitCNY市场价格会得到足够可靠的价格信息,只要鼓鼓钱包功能正常,那么CNY和bitCNY的交易通道就足够流畅,鼓鼓钱包这里就可以统计得到足够准确的市场数据。比以往的算法要有效。


« Last Edit: November 28, 2017, 07:19:14 am by bitcrab »
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