Research Article

Study of Query Expansion Techniques and Their Application in the Biomedical Information Retrieval

Table 7

MAP values to retrieving in Abstract, Title, and MeSH fields using different weighting algorithms.

Combinations Algorithms
BM25 TF-IDF BM25 Raw TF

Porter stemmer-NLM stopwords 0.2717 0.2953 0.2683 0.2209
Porter stemmer-SMART stopwords 0.2733 0.2930 0.2665 0.2221
Krovetz stemmer-NLM stopwords 0.2719 0.2929 0.2684 0.2208
Krovetz stemmer-SMART stopwords 0.2737 0.2904 0.2654 0.2228

The bold font refers to the best values for the parameters.