(7)

in eq. 12, 13 and 14

Dbs(i) #(3) 30

[SE(Dbc(i)/ Dbc(i)+ SE(Dbs(i)/ Dbs(i)]}<sup>2</sup>

SE(log (D)) ={log(D) . [SE(b)/log(fa/(1-fa)-b]<sup>2</sup>

SE(b)/b . SE(m)/m}1/2 **(eq. 14)**

standard error formulas presented in eq. 12, 13, and 14.
