Quote from Lobster:
The real question is: How can we replace the specialist by a computer program, which would be objective, fair, and not greedy?
I'm thinking Why can't a computer provide price improvement?
Here are two ideas. Please feel free to comment.
Method 1:
There is only one print every 15 seconds (or as soon as a certain number of shares have been entered as orders). Each print matches all the limit orders that can be matched plus all market orders at one and the same price. It would be kind of like an opening print every 15 seconds and no other prints. This could be programmed easily and would eliminate the specialist while providing a reward for adding liquidity (other than the miniscule ECN rebates).
Method 2:
Similar to method one, but on a per-user-basis: It would work like a regular ECN (ISLD, Globex, etc.), but if a participant sends in a large marketable order, all the orders he takes out get price improvement accordingly (like it was supposed to be on the NYSE until a few weeks ago). A slight difficulty with this method would be that we would have to make it illegal (or even better impossible) for someone to circumvent this rule by submitting several small orders instead of the big one. My first thought would be that if he sends more than one marketable order within 15 seconds (or whatever time will prove to be reasonable), then the system will amend the prices on all orders except the last one to accurately reflect the fact that it was really one big marketable order sent in several chunks. But of course this rule should not work against the price taker too excessively, so I we should make sure that in no case prices be amended under this rule more than 15 seconds (or whatever time we set for this rule) after the original execution.
So, how about all this?