short ban 对市场的影响

when there are short sellers, bulls know if they keep pushing, at some point shorty have to cover, then they can sell to them to make money.
but right now, this benefit is gone, who want to be the pusher?
and as market make lower high and lower low, bulls getting weaker and weaker, before in this situation we have shorty who made lots of money and they could reverse the course, but now we don't have those money.
short sellers are the major buyers in the first wave of a up trend, because at that time, longs have run out of money to buy.

对vix的影响：
由于不能short很多基金不等不买put来hedge，导致put 量大增因此使得vix比平时偏高。