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by SagelyGuru 5060 days ago
Of course, buying high and selling low is always the 'reason' for making a loss. In this case, I think the program caught itself out by manipulating the market, which it perhaps naively assumed to be non-manipulable.

In other words, it was creating so much volume that, when buying (or selling), it made the market go up (or down). It was then reading the price as going up (or down) and jumping on its own bandwagon. This, of itself, would create growing oscillations in the market and growing losses.

For this to work for you, you need to first create a trend and then sit back and let the suckers pile in on it and take the losses. You then return only when you want to reverse the trend again, at a profitable level (for you). I suspect the program was just too fast for its own good and not a match for the human Masters of this art.

2 comments

That's not what happened, according to nanex.

It just kept making markets in reverse (instead of joining the bid and the offer, it bid on the offer and offered on the bid).

Nanex speculates that Knight ran their tester software on the real market (the tester losing money on purpose to the main algorithm). Alternatively, it could simply be a bug that sends a bid instead of an offer and vice versa. One bit flip at the wrong place could cause that.

Guess their developers never watched "Trading Places"....

"Wilson!!! Get back in there and SELLLLLLLL"