validation of esignal data

[esignal1611]

Does anyone know how to validate how 'clean' eSignal's data is ?
i.e. what assurance is there on their historical tick data, whether for US or foreign indices for example. What checks are in place before as it gets streamed to clients and how are corrections implemented ?
I am currently trying to verify differences with a colleague who uses another data provider. However we would both like to know which one is definitive.

If anyone knows where to get 'accurate' historical tick data for US and foreign indices (1-minute is acceptable), for several years that would be very useful.

I am using Tradestation 2000i and not eSignal's default application as my default platform and any data error correction procedures within the software would be appreciated.

Thanks.

[mburkhart]

"Who has the cleanest data?" is a tough question to answer. The exchanges do their best to put out clean data, and data vendors do their best to keep their historical data clean. The problem is, there is no ::right:: way to clean data.

Your best bet is to educate yourself on what data vendors do to get clean data. There is a great white paper on data scrubbing posted at Tick Data. It describes fairly clearly the difficult choices data vendors face.

http://www.tickdata.com/EquityScrubbing.html

Then you can compare the various methods the data vendors use, and choose one that fits your needs.