本研究以前人論文為基礎，重新檢核前人資料並增補1999年以前與2010年以後之降雨事件，綜合較多且完整的樣本點來分析降雨誘發山崩發生率與雨量因子之間的關係，探討崩壞比是否隨著雨量值改變呈某一趨勢之變化，並觀察研究區各雨量因子之山崩發生降雨門檻值。為了找出能解釋山崩的雨量因子組合並反應不同雨型對崩壞比之影響，考慮的雨量因子包括：最大時雨量、總雨量、平均降雨量強度以及最大3、6、9、12、24小時雨量。 單變量迴歸分析及多變量迴歸分析結果顯示最大1、3、24小時雨量與總雨量因子普遍與崩壞比的擬合度較好而為解釋山崩較佳因子。將崩壞比之觀察值減迴歸結果之預測值得到殘餘值。將殘餘值對時間作圖，觀察崩壞比殘餘值隨時間之變化，結果顯示在台灣中部受集集大地震影響之地區近十年來已有逐漸復育之情形。 ;Based on the previous studies, this study re-examined the previous data and added more data of rainfall events before 1999 and after 2010. This large data set was used to analysis the relationship between rainfall and the occurrence rate of induced landslides. We investigate the trend of landslide ratio with rainfall value and observe the rainfall threshold of landsliding. We find out the relationship between landslide ration and a rainfall factor and the combination of rainfall factors. Rainfall factors used in this study include maximum hourly rainfall, total rainfall, average rainfall intensity and maximum 3, 6, 9, 12, 24 hour rainfalls. The results of univariate regression analysis and multivariate regression analysis showed that maximum hourly rainfall, total rainfall and maximum 3, 24 hour rainfalls are fitting with the landslide ratio well and are more effective in explaining landslides. A residual after regression is defined as the difference between observed value and predicted value for the landslide ratio. We plot the residuals against the time and observe the change of residuals with time. The results showed that the areas affected by Chi-Chi earthquake (central Taiwan) have gradually restored in the last decade.
