Simulation comparisons

Simulation models for boolean-based information retrieval (IR) system performance under varying hypothetical system circumstances are tested to determine maximum performance and minimum space for file structures. While the hashing structure showed the best performance in retrieval time and space economy, the chained hashing structure is better for gradually decreasing term distributions because of minimal retrieval performance variations. The modified hashing structure and the double Balance Implicity Multiway tree structure, however, are best for steep term distributions and more frequently occurring terms.