Rebalancing 131 where the proportionality coefficient is the intrinsic growth rate r. Putting (2)into(①) we get ,(0)=x0 The factor ra on the right side expresses the internal growing tendency of the milkfish, and the factor(1-a/am)expresses the blocking effect of resources and environment on milkfish growth. Obviously, the bigger a is, the bigger rr is, and the smaller is. The growth of milkfish is the result of the co-action of the two factors. Equation(3)can be solved by separation of variables to yield (t) 1+(m-1)e-n We use linear least squares to estimate the parameters r and zm of this model, and express ( 3) T-ST We consult relevant data in Sumagaysay-Chavoso [1998](where the mount of milkfish is the amount harvested over the entire Philippines), insert these data into Matlab, and getr=0.5 and m= 1.9 x 10. Putting these into( 4), we get the changes to the fur nction shown in Figure 5 Figure 5. Milkfish changesRebalancing 131 where the proportionality coefficient is the intrinsic growth rate r. Putting (2) into (1), we get .= X( M X(O)>= X, (3) The factor rx on the right side expresses the internal growing tendency of the milkfish, and the factor (1 - x/xm) expresses the blocking effect of resources and environment on milkfish growth. Obviously, the bigger x is, the bigger rx is, and the smaller (1 - x/x.) is. The growth of milkfish is the result of the co-action of the two factors. Equation (3) can be solved by separation of variables to yield m 1 (4) We use linear least squares to estimate the parameters r and xn of this model, and express (3) as ± r X Xm We consult relevant data in Sumagaysay-Chavoso [1998] (where the amount of milkfish is the amount harvested over the entire Philippines), insert these data into Matlab, and get r = 0.5 and xn = 1.9 x 10'. Putting these into (4), we get the changes to the function shown in Figure 5. x 10, Figure 5. Milkfish changes