The University of California Libraries: A Plan for Development (1977)

170 The University of California Libraries
As noted in Chapter IV, not all books are needed immediately;
there are, in fact, gradations in the immediacy of need for materials,
and recognition of these gradations should enable the University to
respond in a differentiated way to user's needs. By doing so, in
fact, it should be possible to provide a higher degree of user satisfaction
at all levels, as discussed in previous chapters.
So far as housing of materials is concerned, this means that
alternatives to the conventional methods of shelving may appropriately
be considered. Typically, alternative shelving methods involve
more compact arrangement of books on the shelves, and may use mechanical
devices to store and retrieve the books. By some methods, as
many as 80 or more volumes per asf may be shelved, as opposed to 10
to 15 volumes per asf in conventional libraries.
Estimating the Amount of Material to be Placed in Compact
Shelving. For the purpose of projecting the amount of material that
might be considered for such compact shelving, the same approach was
used as for the weeding alternative; that is, it was assumed that
only materials that are likely to be used infrequently would be eligible
for such treatment. This assumption is important, because some
degree of inconvenience to the user is inevitable in such techniques.
As discussed later, the ability of the user to browse (or, more
precisely, to consult bodies of material on the same subject) may be
reduced, depending on the method employed. The location of materials
may also be remote from a campus, which imposes a delay in
delivery of the material. Only if the need to consult such materials
is likely to be intermittent and relatively infrequent, then, should
they be considered for compact shelving.
For the space model, the amount of material eligible for such
treatment was projected by calculating the number of volumes that
have not circulated within the last 12 years. This approach is
based on a number of studies, all of which indicate that the best
predictor of future demand is the date of last circulation. In a
landmark study, Fussler and Simon analyzed various aspects of the
use of books in the University of Chicago library, and concluded