MODELING OF ANALOG FILM-FILE RADIOGRAPHIC RETRIEVALS : A MARKOV CHAIN

RATIONALE AND OBJECTIVES: Existing retrieval models for radiology film libraries have not incorporated the influence of previous retrievals. A Markov chain model for the retrieval rates from an analog film library is proposed as a means of considering this effect. METHODS: A Markov chain model was developed for the retrieval rates of an analog film library. The Markov chain model required identification of the states of the Markov chain, the required one-step transition probabilities between states, and the initial state probabilities. RESULTS AND CONCLUSIONS: The results from the Markov chain model compared favorably with the 30-day measurements (25,775 retrievals), but a large enough sample to determine a statistical confidence level was not considered.