The quadrat test is a test of complete spatial randomness (CSR) that uses the statistic based on quadrat counts. In the quadrat test, the study area window W is divided into subregions called quadrats (,,....) of equal area. The test counts the number of points that fall in each quadrat for . Under the null hypothesis of CSR, the are iid Poisson random variables. The following Pearson test statistic assesses whether there is a departure from the homogeneous poisson process:
A significant p-value indicates that the underlying point pattern is not CSR.