The research and optimization on levenberg-marquard algorithm in neural net

After analyzing the traditional levenberg-marguard algorithm and its properties of quadratic function, and combining with Tara formula, i find that it inherits the properties of image of quadratic function. It approximate the axis of symmetry. Through judging the plus and minus of the second derivative, it accelerates the change of damp fact. and make the transforming between of gauss newton method and steepest descent method quicklier. It makes the algorithm more efficient. It shows its efficiency and accuracy by experiments.