Dr. Carron has compiled a tariff for Kowen Forest using Method 3. The form of this tariff is:
                v	= a + b hdom + c hdom2 + d g + e g hdom
    i.e.	      v	= (a + b hdom + c hdom2) + (d + e hdom)g
                    = k1 + k2 g for a given predominant height
 where  	v  	= merchantable volume of the individual tree
          hdom	= stand predominant height
	           	g 	= tree baob.

The expressions for k1 and k2 respectively imply a curvilinear relationship between the regression constant and predominant height and a linear relationship between the regression coefficient and predominant height.

For direct estimation of stand merchantable volume, the Carron tariff becomes :
	              V 	=  N (a + b hdom+ c hdom2) + (d + e hdom) Σ g
 		where	V 	= stand volume
			        	N 	= number of trees in the stand
			     Σ g	= stand baob (G)