I've removed the Fee Rate since it was just confusing in the Exchange, for the record it's the price at which an asset, say USD, will be converted to BTS in order to pay for fees.
The settlement price is the price which used to be called the Feed Price.
The Margin Call Price is the Settlement Price * Squeeze Protection Ratio (initially at 1.5, now somewhere around 1.1)
Your margin position will get margin called if the call price of the position falls below the margin call price.
First off. Thank you for this answer. I have learned a bit from your answers, but i am still a bit confused.
1. I do not understand the fee rate. I cannot imagine why there is a fee or what it is for. Does this account for the penalty that we pay when we get margin called of 5%. Is that what this fee represents? Could you explain this fee please.
2. I understand that when we loan USD into existence we need to put up collateral of 1.75 the value. If i understand correctly should the price change so much that our collateral becomes less than the margin call price (1.1) we would get margin called. That means our position would be closed, the collateral would be used to force us to buy the USD we need to close the position. I don't understand the price that would be used and who would sell us the USD. Is it so that we would simply get the best price at the market? So whoever has put up the best sell price for the amount of USD that we need to close the position would get our BTS from our collateral. What happens if the collateral is less than the best sell price? Or if there is no seller? What would happen if we had USD on our account. Would I simply use the USD from my account and get my collateral back?
1. The fee rate has nothing to do with margin calls. All transaction fees are ultimately payed in BTS, so if a user has no BTS he automatically trades the asset in which he's transacting for BTS to pay the fee. Each asset has a "fee pool" of BTS to support this, and the trade takes place at the fee rate. The fee pool I believe is funded by the asset issuer.
2. Margin calls are triggered by the price of the cheapest available asset on the internal market, not by the feed price. When a margin call is triggered, the collateral will be used to buy any of the asset that's available for sale cheaper than [feed price * maximum short squeeze ratio] to cover the position. It will not touch any other assets in the users account, even if they could be used to cover the position.
This isn't a complete answer, but I hope it helps.