(1) create the fishnet

(2) join the point to fishnet. click the fishnet to choose the joins and relates/join/join data from anther layer based on spatial location

(3) join the M_ij and N_ij tables togother.

(4) calculate the M_ij/N_ij

(5) seelect the shapfile by Analysis tools/extract acoording to the weight value

    a. to choose the N_ij >0 to generate a1

    b. to choose the 0<N_ij<N_av to generate a2 based on a1 and times 0.2 for the ratio

    c. to choose the N_av<=N_ij<1.5N_av to generate a3 based on a1 and times 0.4 for the ratio

    d. to choose the 1.5N_av<=N_ij<3N_av to generate a4 based on a1 and times 0.7 for the ratio

    e. to choose the 1.5N_av<=N_ij<3N_av to generate a5 based on a1 and times 1 for the ratio

(6) merge the a2,a3,a4,a5 to one shpfile by Analysis tools/overlay/update

(7) to change the color or classfy the file. Maybe the dissolve to merge all the polygon(like fishnet) to one.

(8)finish.