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Temperature dependences of the total effective trap density Neff and the electro-optic coefficient r33 in Ce-doped and Rh-doped BaTiO3 were determined by two-beam coupling measurements. It was found that the effective trap density Neff of BaTiO3:Ce increases whereas that of BaTiO3:Rh decreases with increasing temperature. The electro-optic coefficient r33 of both crystals increases with temperature. The photorefractive response times were also measured and found to decrease with different rates as temperature increases in the two crystals. The results were discussed by using the two-centre model for BaTiO3:Ce and three-charge-state model for BaTiO3:Rh. We found that the different temperature dependence of Neff in the two crystals was due to the fact that the deep- and shallow-trap levels in BaTiO3:Ce are caused by different impurity centres whereas those in BaTiO3:Rh are caused by different charge states of the same impurity centre.