Abstract: Grouped data Logistic model is a scheme for the solving the problem of whose dependent variable is a qualitative variable and independent variable is a categorical variable. Weighted least square is used to solve grouped data Logistic equation. New west area in Wushan county was chosen as experimental area. A grouped data Logistic model was set up based on that lithological characters, gradient, height, groundwater level depth and nearest distant of effected structure line were taken as independent variables. Historical landslide was taken as dependent variable. The second step was prominent testing of equation and regression coefficient. At last, slope stability was predicted by regression equation in the experimental area. The model predicts actual landslide occurrence at 72.55% accuracy and landslide nonoccurrence at 79.69% when criterion of probability is equal to 0.157 9.

Key words: GIS, grouped data, Logistic model slope, stability