Detection efficiency calibration based on correlated photons is a high precision calibration method at the single photon level. During the calibration process, measured time, photon count rate, and channel detection efficiency are important experimental parameters that affect the measured uncertainty of detection efficiency. This paper constructs simulation models of measured uncertainty with experimental parameters by the correlated photons method. Our experiment measures and predicts the uncertainty when parameters change. This research provides a quantitative basis for experimental parameter settings of calibration of single photon detectors using correlated photons technology.