  This paper introduces the concept of accessibility from the field of
transportation planning and adopts it within the context of Information
Retrieval (IR). An analogy is drawn between the fields, which motivates the
development of document accessibility measures for IR systems. Considering the
accessibility of documents within a collection given an IR System provides a
different perspective on the analysis and evaluation of such systems which
could be used to inform the design, tuning and management of current and future
IR systems.
