1. A method for computing a variogram model, which comprises: selecting input parameters using a computer processor; displaying a variogram map, the variogram map comprising a maximum direction of spatial continuity; displaying a rose diagram, the rose diagram comprising an edge and a plurality of vectors; rotating only the edge of the rose diagram to align the maximum direction of spatial continuity with an axis of the rose diagram; and adjusting only the edge of the rose diagram until the edge of the rose diagram meets each end of each longest and shortest rose diagram vector.