A NOVEL WAY TO ANALYZE COMPETITIVE PERFORMANCE OF ONLINE ALGORITHMS——INSTANCE TRANSFORMATION BASED METHOD

A competitive analysis method for online algorithms is developed based on the idea of instance transformation.The method begins with an arbitrary instance,and transforms the instance along the direction of its performance ratio increasing,moreover the eventual instance after transformation shows a more special structure of which we can take advantage to analyze its performance ratio.This presented method is applied on a single machine online scheduling problem of minimizing the total weighted completion time.We give an alternative proof of an existing conclusion about the competitive performance.