Question Regarding Standard Deviation on Array - correct MA_Period???
Standard Deviation formula is different calculated in different
platforms (groups, individuals), mostly is based on change on smoothed
price (ex.: get iStdDev from Moving Average indicator), but you can do
the same but with actual Close prices ( or OHLC ) and by percent
changes with same data (periods or ticks) and compare in MT4 and excel.
Hi,
I wondered whether anyone can shed some light on this problem I'm experiencing with istddevonarray().
If I calculate the standard deviation for a set of prices held in an array in MT4 I get a completely different result compared to calculating the STD in Excel using the STDEVPA function and the same data held in the array.
I can change the results I get in MT4 by changing the MA_Period setting in the iStdDevonarray function.
My array holds 2686 data items. To get an STD the same as the result supplied in Excel what Period should I use for the MA?
Regards