Hi,
the
best suitable data provider is pretty important to traders.
Sources often mentioned are Brokers like
InteractiveBrokers and data providers like
eSignal and
DTN.
Which of them is the best provider?
It depends on your trading needs, since each possibility has got some shortcomings.
Data Providers like
eSignal and
DTN offer full data supply and comfortable backfill possibilities.
But just this attractive huge data offer may render their service useless for fast trading.
As underlined by a lot of posts (
1,
2,
3) in news times there may be
up to 10 seconds delay till you get the needed data.
So such data providers may be best choice only to traders who need exact data for longer term decisions and comfortable backfill sources.
In contrast to these data providers Interactive Brokers delivers its data even in news times with maximal 0.4 seconds delay.
Fast enough for any usual trade.
But their data have got some shortcomings too. Details are explainded by
Kiwi_Trader .
IB Data are coming in very fast, seemingly tick by tick, but they are no tick data (tick in the sense of single trade) but in principle 0.3 second bar data.
For Day traders 0.3 second bars now would by far be better than tick data with 10 seconds delay.
But IB Data have got a second shortcoming: Until now they deliver bars with open and close price only.
High and low are omitted and the confusing expression 'snapshot' invented for this data crippling process.
So until now the day trader has got the choice between data useless by delay and data
dangerous by crippling.
But there is hope. Maybe Interactive Brokers is
changing it's policy and adding high and low to their data in future.
Martin