Index | Formula | Explanation and significance of formula |
Coefficient of variation | (1) | CV represents the coefficient of variation of Tyson polygon area in characteristic town; denotes the area of the ith Tyson polygon; n is the number of Tyson polygon; is standard deviation; is average value; 33% < CV < 64% is random distribution; CV ≥ 64% is clustered distribution; CV ≤ 33% is uniform distribution |
Nuclear density estimation | (2) | is the nuclear density estimates; is a kernel function; T denotes the number of characteristic towns; h > 0 is bandwidth; is the distance from the valuation point x to the event point . The larger the nuclear density estimation, the more dense the points, the higher the probability of regional events. |