  Measurements have been performed of the resistivity of the samples of MgB2,
AlB2 and AgB2. The samples show presence of impurities. Analyzing the data in
terms of the impurity scattering, electron-phonon scattering, and weak
localization it has been found that the AlB2 (AgB2) sample involves maximum
(minimum) effect of the impurity, electron-phonon interaction and weak
localization.
