For n-type semiconductors, we have separated the r(m) depending on the anisotropy of occupied valleys from the Hall factor and analyzed it for growth with various orientations and under different strain conditions. In order to calculate the r... for the arbitrary growth direction, the expressions of eta(ii)(s) , n(jj)(s), and eta(ii)(s)eta(jj)(s) -eta(ij)(s)eta(ji)(s) for both the direct and indirect conduction valleys are obtained as functions of the transverse and longitudinal masses for an ellipsoid. In particular, the r(m)'s for the [001], [110], and [111] growth directions are formulated by using the ratio of the longitudinal mass to the transverse mass for occupied valleys. (C) 2004 Elsevier Ltd. All rights reserved.