As any ordinary person knows, the shortest distance between two points is a straight line. What, then, is the shortest distance between three points? Four points? The study reported in this article deals with the observed actions of Turkish student mathematics teachers as they were working with minimal network problems. Having analysed the…

Discusses the use of the least-squares regression line in determining the optimum straight line in an efficient and objective manner and the validity of its underlying assumptions in certain situations. Discusses the treatment of kinetic data, distortion from large errors, and the Guggenheim method. (JRH)

Three techniques for determining a straight line fit to data are compared. The methods are applied to a range of datasets containing one or more outliers, and to a specific example from the field of chemistry. For the method which is the most resistant to the presence of outliers, a Microsoft Excel spreadsheet, as well as two Matlab routines, are…

Teachers and coaches can help tennis players develop accuracy in the forehand and backhand strokes by using the "straight line" or "flattened arc" concept. The four elements essential to proper execution of these strokes are explained, and drawings are provided which demonstrate the straight line concept. (IAH)

In the nineteenth century many people tried to seek a value for the most famous irrational number, [pi], by means of an experiment known as Buffon's needle, consisting of throwing randomly a needle onto a surface ruled with straight parallel lines. Here we propose to extend this experiment in order to evaluate other irrational numbers, such as…

The material is designed to help pupils investigate how the value for slope in the equation of a line affects the inclination for the graph of an equation. A program written in BASIC designed to run on an Apple microcomputer is included. Worksheet masters for duplication are provided. (MP)

The method of least squares enables the determination of an estimate of the slope and intercept of a straight line relationship between two quantities or variables X and Y. Although a theoretical relationship may exist between X and Y of the form Y = mX + c, in practice experimental or measurement errors will occur, and the observed or measured…

Two sophisticated--autoregressive integrated moving average (ARIMA), straight-line regression--and two naive--simple average, monthly average--forecasting techniques were used to forecast monthly circulation totals of 34 public libraries. Comparisons of forecasts and actual totals revealed that ARIMA and monthly average methods had smallest mean…

Two techniques for determining a straight line fit to data are compared. This article reviews two simple techniques for fitting a straight line to a set of data, namely the method of averages and the method of least squares. These methods are compared by showing the results of a simple analysis, together with a number of tests based on randomized…

Outlines techniques in the design and composition of outdoor photographs. Suggests creative adjustments to the visual image when the interesting aspect of the scene is action; linear motion; fast or slow speed; straight, curved, or parallel lines; circles; colors; light; texture; unusual size or shape; or patterns. (SV)

Presented are activities concerning the method of graphing the equation y=kx in the Cartesian and other coordinate systems. Students progress from the graph of a straight line to the investigation of conceptually related geometric loci in non-Cartesian coordinate systems. (MDH)

The author examines certain areas of confusion which arise in the teaching of linear equations for lines. (SD)

This column describes how a university clinic (henceforth "the Clinic") specializing in treating children with anxiety disorders managed over time to integrate empirically supported treatments and diagnostic methods, initially with obsessive-compulsive disorder (OCD) and later with other anxiety disorders as well, over the 15-year period 1991 to…

Four methods were used to forecast monthly circulation totals in 15 midwestern academic libraries: dummy time-series regression, lagged time-series regression, simple average (straight-line forecasting), monthly average (naive forecasting). In tests of forecasting accuracy, dummy regression method and monthly mean method exhibited smallest average…

Standard calculus textbooks often include a related rates problem involving light cast onto a straight line by a revolving light source. Mathematical aspects to these problems (both in the solution and in the method by which that solution is obtained) are examined. (JN)