In this paper the amount of frustration in a section of books is derived from a model that includes the effects of variable book circulation and the nondeterministic nature of book use. (Author/DH)

Some reasons are offered for the differences between survey findings and econometric results. (Editor)

A review is given of doubly-chained trees for information retrieval. It is shown that the chaining steps may be of different cost depending upon whether the step is vertical or horizontal. The problem of constructing an optimal retrieval tree is formulated mathematically and a solution procedure given. (5 references) (Author/KE)

A Mathematical model for use in studying how to minimize the cost of operating a mechanized retrieval system is developed. Through the use of cost analysis, the model provides a method for comparative evaluation between information retrieval systems. (15 references) (Author/SJ)

Presents the derivation of rotation and reflection matrix representation of symmetry operators as used in the initial discussion of crystal symmetry in elementary mineralogy at Iowa State University. Includes references and an appended list of matrix representations of the important crystallographic symmetry operators, excluding the trigonal and…

A forecasting method using an estimate of ultimate level of adoption and expected time scale. (RA)

A mathematical model is presented which explains the observed exponential growth rates of citations and references in a scientific discipline. The independent variables are the growth rate of the number of articles published and the decay rate of citation of old literature. (13 references) (Author)

This Nobel lecture describes the development and role of maximum principles in economic research as practiced by the author. (AL)