Buy/Sell Volume Approximation?

[Geester]

Hi there,

Is there an accepted "formula" to approximate buy/sell volume on historic bars?

I thought that using price action on the bar, you could perhaps apportion part of the bar's volume based on the distance of close from the high as selling, and close to the low as buying. This sounds way too simplistic but perhaps there is some way of doing it?

If anyone has ideas, I'd be keen to hear them.

Many thanks indeed.

G.