Institute of Information Theories and Applications FOI ITHEA
Similar to Genetic algorithm, Evolution strategy is a process of continuous reproduction, trial and
selection. Each new generation is an improvement on the one that went before. This paper presents two different
proposals based on the vector space model (VSM) as a traditional model in information Retrieval (TIR). The first
uses evolution strategy (ES). The second uses the document centroid (DC) in query expansion technique. Then
the results are compared; it was noticed that ES technique is more efficient than the other methods.