Presents a short study of proper values of two-by-two matrices with real entries. Gives examples of symmetric matrices and applications to systems of linear equations of perpendicular lines intersecting at the origin and central conics rotated about the origin to eliminate the xy term from its equation. (MDH)

Describes a theoretical development to explain the shadow patterns of an object exposed to an extended light source while held at varying distances from a screen. The theoretical model is found to be accurate in comparison with experimental results. (MDH)

Presents a public-key cryptosystem application to introduce students to several topics in discrete mathematics. A computer algorithms using recursive methods is presented to solve a problem in which one person wants to send a coded message to a second person while keeping the message secret from a third person. (MDH)

Modifications to current methods of calculating and reporting financial ratios are outlined for college managers. The modified ratios, felt to be more realistic, are illustrated with applications in three areas: (1) student revenues; (2) endowment and other investment income; and (3) public and private gifts, grants, and contracts revenue. (MSE)

Discussion of user queries in information retrieval highlights the experimental evaluation of an adaptive linear model that constructs improved query vectors from user preference judgments on a sample set of documents. The performance of this method is compared with that of standard relevance feedback techniques. (28 references) (LRW)

After discussing the role of supercalculators within the business calculus curriculum, several examples are presented which allow the reader to examine the capabilities and codes of calculators specific to different major manufacturers. The topics examined include annuities, Newton's method, fixed point iteration, graphing, solvers, and…

Presented is a method for factoring quadratic equations that helps the teacher demonstrate how to eliminate guessing through establishment of the connection between multiplication and factoring. Included are examples that allow the student to understand the link between the algebraic and the pictorial representations of quadratic equations. (JJK)

Ohio State University developed a formula to calculate the annual and renovation budget necessary to maintain campus facilities. The calculations can indicate whether an institution is gaining or losing ground in facilities upkeep. Many institutions need to nearly double past efforts to retain physical plant quality and maintain facility…

A college or university thinking of leasing out facilities for an auxiliary activity on campus should consider including a percentage rent provision in the contract, to benefit from increased sales. Issues to consider include definitions and reporting of gross sales, audits of reported sales, and auditing procedures and reporting. (MSE)

Reviews the development and the principal elements of total quality management (TQM) and demonstrates methods for introducing some of the key elements into a strategy-oriented business simulation game that can be used to teach future managers. Topics discussed include increased focus on the customer; continuous improvement; and competitive…

A common misconception among students setting up force-acceleration problems is to think of the expression "mass times acceleration" as a force itself. Presents a new formula to express the relationship between force, mass, and acceleration, and discusses its benefits. (MDH)

Introduces a new sign convention for the object and image distances involving mirrors and lenses. Proposes that the method is easier for students to understand and remember and that it helps clarify the physics concepts involved. (MDH)

Presents Heron's original geometric proof to his formula to calculate the area of a triangle. Attempts to improve on this proof by supplying a chain of reasoning that leads quickly from premises to the conclusion. (MDH)

Examines the 80/20 rule that relates to productive sources in a bibliography. Highlights include applications in library acquisition policies, library circulation and weeding policies, science policy studies, information science, and econometrics; formulae of Burrell and of Egghe; probabilistic proofs; geometric distributions; Lotka distribution;…

Discusses computer access in schools; explains how to determine sufficient quantities of computers; and describes a formula that illustrates the relationship between student access hours, the number of computers in a school, and the number of instructional hours in a typical school week. (six references) (LRW)