Quote from propseeker:
yes, they do... that sounds like your vendor's feed implementation.
At NASD or ARCX level, they still have lots of one-sided orders? I thought that the trading is so intense that there shouldn't be lots of one-sided orders. Currently the number of one-sided messages is about 1/3 of total messages.
I thought they could always aggregate two opposite orders into one message and send that message out, because it's so liquid.
Otherwise, does <1% of cancellation make sense for QQQQ?
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