Dependence of temperature on resistance of photo conductor

As we know, for a photo conductor resistance tends to decrease with increase in irradiance, but with greater irradiance comes greater temperature. Also we know, photo conductors are semiconductors,whose resistance decrease with increasing temperature. So, can we link these two effects (increasing irradiance and increasing temperature) and say that the amount of decrease in resistance observed is cumulative effect of both? Any mathematical relation will also be helpful. Thanks in advance...!