Research Article
Study of Query Expansion Techniques and Their Application in the Biomedical Information Retrieval
Table 8
Finding the best values of the parameters for TF-IDF BM25 feedback.
(a) The best value for the parameter |
| Combinations | Parameters | | | | | | | | | | | | | Baseline | 10 | 10 | 0.5 | 5 | 10 | 0.5 | 15 | 10 | 0.5 | 30 | 10 | 0.5 |
| Porter stemmer-NLM stopwords | 0.2079 | 0.1991 | 0.2070 | 0.2053 | 0.1868 | Porter stemmer-SMART stopwords | 0.2075 | 0.2026 | 0.2053 | 0.2052 | 0.1898 | Krovetz stemmer-NLM stopwords | 0.2094 | 0.1974 | 0.2007 | 0.2025 | 0.1843 | Krovetz stemmer-SMART stopwords | 0.2074 | 0.1998 | 0.2022 | 0.2056 | 0.1866 |
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The bold font refers to the best values for the parameters.
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(b) The best value for the parameter |
| Combinations | Parameters | | | | | | | | | | | | | | | | 10 | 10 | 0.5 | 10 | 20 | 0.5 | 10 | 30 | 0.5 | 10 | 40 | 0.5 | 10 | 28 | 0.5 |
| Porter stemmer-NLM stopwords | 0.2079 | 0.2103 | 0.2117 | 0.2102 | 0.2116 | Porter stemmer-SMART stopwords | 0.2075 | 0.2083 | 0.2105 | 0.2087 | 0.2100 | Krovetz stemmer-NLM stopwords | 0.2094 | 0.2068 | 0.2075 | 0.2068 | 0.2093 | Krovetz stemmer-SMART stopwords | 0.2074 | 0.2061 | 0.2015 | 0.2032 | 0.2033 |
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The bold font refers to the best values for the parameters.
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(c) The best value for the parameter |
| Combinations | Parameters | | | | | | | | | | | | | | | | 10 | 28 | 0.5 | 10 | 28 | 0.1 | 10 | 28 | 1 | 10 | 28 | 0.9 | 10 | 28 | 0.4 |
| Porter stemmer-NLM stopwords | 0.2116 | 0.1957 | 0.2103 | 0.2099 | 0.2105 | Porter stemmer-SMART stopwords | 0.2100 | 0.1956 | 0.2035 | 0.2091 | 0.2093 | Krovetz stemmer-NLM stopwords | 0.2093 | 0.1904 | 0.2072 | 0.2097 | 0.2089 | Krovetz stemmer-SMART stopwords | 0.2033 | 0.1932 | 0.2024 | 0.2031 | 0.2061 |
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The bold font refers to the best values for the parameters.
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