Matching text sets is disclosed, including: extracting a text set from data associated with a current period; storing the text set with a plurality of text sets; extracting a keyword from the text set; determining a weight value associated with the keyword associated with the text set; determining a degree of similarity between the text set and another text set based at least in part on a weight value associated with the keyword associated with the text set and a weight value associated with a keyword associated with the other text set; and determining whether the text set is related to the other text set based at least in part on the determined degree of similarity.