Hello, I am testing my new system and I was wondering how TWS papertrading account simulate fills. I read somewhere on the website that it was simulated "with the top of the book". Does it mean that your buy limit order has to be touched by the real time ask to be filled? I was thinking they were using prints , like if the last real time print is one tick under your buy limit order then you get it... I f someone knows how they are simulated? Thanks a lot.
I dont know how they simulate but you dont need to get hit to get a fill. It seems to me that they sort of find a way to assume you would have get the fill. For example if you bid 6.25 on a low liquidity stock 10@ 6.25 5@ 6.35, you most probably need to get hit. But if you Bid 75.57 on XOM and it is 50@75.57 25@75.59 you can get filled long 75.57 on the bid if there are many trades going on at he price. Also, slippage can be very bad. If you go market I noticed that it can take some time to get filled but with a real account you get fillled almost instantly. Play with it, you will see and develop a feeling for it. Some people say it's bad but I think it's better than nothing. If you want to test strategies that are highly sensitive on the fills (scalping...) then I dont think you can test it with a high degree of confidence.
Yes I know Total Kheops that it's almost impossible to test a scalping strategy... So according to you, IB uses prints to simulate fills? In this case, I think they wait for a lower bid or higher ask to be filled in real time, right?
Log into the account management. Look on the left down in the menu somewhere. You need an actual trading account to get a paper one.