... than that of simulation. This can be attributed to both of the large interval of rainfall data and the changes of basin characteristics. The calibrated parameters were afterward verified using ... be obtained directly from measurable quantities of basin characteristics [6] and hence model calibration is needed. Using the observed rainfall and evaporation data of each storm event as inputs, ... much easier and quick to find the best overall parameters than the traditional trial -and- error method. Keywords: Rainfall-runoff, event data, auto- calibration, trial -and- error, searching space....