I was recently asked why I use an RSI setting of 9 rather than a...

I was recently asked why I use an RSI setting of 9 rather than a setting of 14.

Further to that, you might like to have a look at the following research:

http://ibankcoin.com/woodshedderblog/2009/05/08/rsi-testing-for-a-predictive-period-setting/

It seems that using very high readings on very short term RSIs have high predictive reliability over short time frames; e.g., RSI.2 above 90 - go short for the next two days.

The author also notes:

"I will leave on this thought (If only to stir up some controversy/discussion): it appears that the standard RSI setting of 14 has been almost useless, over the past 16 years, as an overbought indicator."

I might add - RSI.9 is not a lot better. :)

I could add a lot of critical commentary on the research - but I'll leave it at this for the time being and let you do your own thinking and research.

Redbacka