Abstract: To extract geometrical property by abstracting the contour and skeleton of digits can obtain the particulars efficiently, but irregularity induces low recognition rate. I}he statistical analysis theory can overcome the weakness.First, Gap-Rate and Gap-Variation extraction methods were probed, by projecting and computing the rate and change of each gap as the eigenvector of the digit Further,Rotational Projection was probed based on the idea of enhancing the orthogonality of cigenvcctors and reducing the redundancy information in the way of rotating the datum line. I}heoretical analysis and experiment proved the high recognition rate of rotational projection with the same statistical properties, also parameters were recommended in the end. Further more, it also recognizes the oblique digit.

Key words: Statistical analysis, Rotational projection, Naive bayes, Minimum nearest neighbor method, Handwritten digit recognition