2018-02-16 09:51:51 +00:00
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BSIP: 0030
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Title: Always Allow Increasing Collateral Ratio If Debt Not Increased
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Author: Abit More <https://github.com/abitmore>
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Status: Draft
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Type: Protocol
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Created: 2018-02-16
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Discussion: https://github.com/bitshares/bitshares-core/issues/583,
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https://github.com/bitshares/bitshares-core/issues/672
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Replaces: -
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Worker: To be done
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# Abstract
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Currently, when a short position's collateral ratio is below MCR (a parameter
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in price feed: `maintenance_collateral_ratio`) but is not completely filled
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immediately due to a lack of enough volume on the opposite side of the market,
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it will hang in the market and be waiting for being margin called.
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The owner then can adjust the order's collateral ratio **only if**
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* to close the position, or
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* the new collateral ratio is above MCR, or
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* the call order get completely filled (margin called) immediately.
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While this prevents shorters from maliciously reducing collateral ratio (to
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increase possibility of black swan event), it also prevents shorters from
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slightly increasing collateral ratio (to decrease possibility of black swan
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event).
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This BSIP proposes a mechanism to improve this situation.
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# Motivation
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Make the exchange system more user-friendly.
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2018-02-18 13:22:19 +00:00
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# Rationale
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2018-02-16 09:51:51 +00:00
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The ecosystem would get benefit if shorters are allowed to reduce risks to
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themselves while reducing risks to the system at same time.
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Current rules are a bit too strict, which can be loosed to:
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A shorter can adjust the position's collateral ratio **only if**
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* to close the position, or
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* the new collateral ratio is above MCR, or
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* the call order get completely filled (margin called) immediately, or
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* **the new ratio is higher than old ratio and debt is not increased**
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# Specifications
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In `do_apply()` function of `call_order_update_evaluator` class, if
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finally found the call order still in margin call territory,
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* don't throw an exception if `call_obj->collateralization()` is reduced, and
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* require `delta_debt` of `call_order_update_operation` to be non-positive.
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# Discussion
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[to be added if any]
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# Summary for Shareholders
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[to be added if any]
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# Copyright
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This document is placed in the public domain.
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# See Also
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* https://github.com/bitshares/bitshares-core/issues/583
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* https://github.com/bitshares/bitshares-core/issues/672
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* https://bitsharestalk.org/index.php?topic=25926.0
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