We measured the longitudinal and Hall resistive transitions of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ films in applied fields up to 9 T. The longitudinal fluctuation conductivities obey the scaling behavior of the three-dimensional Hartree fluctuation theory of Ullah and Dorsey. The fluctuation Hall conductivities do not scale. Our analysis shows that there are substantial contributions from the Maki-Thompson (MT) process as well as the Aslamazov-Larkin (AL) one. Using an ansatz suggested by the microscopic theory of Fukuyama et al., we separated the AL term from the total fluctuation conductivity. The AL Hall conductivity follows a scaling law, and the AL and MT terms have opposite sign. The sign of the AL term is consistent with the sign change in the flux-flow regime, as predicted by theory. At low fields and temperatures just above ${\mathrm{T}}_{\mathrm{c}}$(H), the AL term dominates the MT term, therefore causing the total Hall-conductivity sign change.
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