Research on the Characters of Four Sequential Patterns Mining AlgorithmsLU Feng,ZHANG Wei-wei(School of Information Engineering,Wuhan University of Technology,Wuhan 430070,China)Sequential patterns mining was a very important data-mining problem with board application.We researched four sequential patterns mining algorithms namely AprioriAll,GSP,FreeSpan,Prefixspan,and studied their characters.A qualitative analysis had also been made on the algorithm's time and space efficiency.We also pointed out the conditions in which each algorithm was applied.The conclusion of the research would be beneficial to the design of data mining system.sequential patterns mining;aprioriAll;GSP;freespan;prefixspan