Which 'open' to consider?

[AndrewCib]

For trading system development, I am currently analyzing the EOD data of various markets. However I am not sure which market 'open' should I choose - the actual market open as stated by many market data providers or the futures' open?

The market open used by data provides like Yahoo/Google is quite near to the previous close - and doesn't take into account the gaps.

Which one is more effective in analysis? What do you use?

[AnettaHouri]

Could you be a bit more vague?

Forex, Futures, Stocks, Bonds????

[Andrewsolkaf]

Basing TA on the Open value is fraught with risk. For example, different data providers quote the FTSE100 Open as the previous day's Close, the value at 08:00am or the value at 08:02am. Overnight gaps mean such discrepancies can be significant. The FTSE is an index that actually has a closed session overnight, i.e. it is not being continuously re-calculated. But spreadbet markets derived from the FTSE (as well as Forex etc.) are open throughout the 24 hours, so Open in that context has much less meaning.

[Angelo59V2]

My advice is pick any (toss a coin to decide if you must) then get stuck into the reseach ASAP and get your feet wet

[AnNor]

Thanks for all the replies.

Yes it has been my experience - data for Open is quite erratic between the data providers.
Can any one please share a good source of reliable data for futures' [DJIA/FTSE]?