Presents a mathematical definition of the probability-weighted amount of information (PWI), a measure of term specificity in documents that is based on an information-theoretic view of retrieval events. Corresponds with the term frequency-inverse document frequency (tf-idf) measures that are used in information retrieval systems. (Author/LRW)

Proposes a mathematical model using the probability formalism to explain why a geometrical law is observed in distributions related to library circulation data. Highlights include techniques based on convolution theory; Lotka's law; and Bradford's law. (Author/LRW)

Describes a study that investigated document retrieval relevance based on document length in an experimental text collection. Topics include term weighting and document ranking, retrieval strategies such as the vector-space cosine match, and a modified technique called the pivoted cosine normalization. (LRW)