"The term nomography serves to designate the general study of the graphic representation of equations in any number of variables on a plane surface. Its practical applications consist in the representation of the numerical relations between the variables by calibrated systems (straight lines or curves) constructed once for all and permitting the determination by a single reading of one or more of the variables when the others are given." (Howard G Funkhouser," Historical Development of the Graphical Representation of Statistical Data", 1937)
"Now the condition that in the intersection chart three straight lines shall meet in a point is identical with the condition that in the corresponding alignment chart three points shall lie on a straight line. This is called the 'principle of duality', and this condition is given in the form of a determinant, known in nomography as the 'basic nomogram determinant', which enables us to plot the three scales of a nomogram, whether they are straight or curved, on squared paper. Whenever it proves possible to transform an equation into the form of a basic nomogram determinant a true nomogram can be drawn, but only too frequently this proves to be impossible and recourse must be had to graphical methods." (Philip Lyle, "The Construction of Nomograms for Use in Statistics: Part I. True and Empirical", Journal of the Royal Statistical Society - Series C (Applied Statistics) Vol. 3 (2), 1954)
"A nomograph of a formula is a graph or diagram composed of lines scaled relatively and placed in such relative positions that the values of the variables are found on a line crossing the scales. The object is to substitute for the labor of computation a simple mechanical operation such as the one previously described. It is easy to read a nomogram with precision because of the few lines. It provides a tabulation of all possible values, enables solutions to be made irrespective of what quantity in the formula is unknown and also enables one to observe instantly the effect of a change, either small or great, in any one of the variables. The principles of such diagrams may be given in a general way and simple nomograms be constructed, but equations with many unknown quantities cannot be solved graphically without higher mathematics." (William C Marshall, "Graphical methods for schools, colleges, statisticians, engineers and executives", 1921)
"Nomograms are graphic devices for representing equations on a plane surface. They are widely used in engineering design and to a lesser extent in the social and physical sciences. Nomograms can be divided into two classes, or distinct graphic formats: (i) Abac: Equation drawn as a graph on Cartesian or logarithmic coordinates. (ii) Alignment chart. Three or more scales arranged so that a straight line joining two known values cuts the third scale to give the required value." (Michael Macdonald-Ross, "Graphics in Texts", Review of Research in Education Vol. 5, 1977)
"Since the chief purpose of the nomogram is to make exact data available for operational use, its chief competitor is the table. Operational tables may break Ehrenberg's two-digit rule, since they are not used to detect general trends but to provide exact data for some operational purpose. The choice between nomogram and table involves a complex tradeoff among cost, space, convenience, accuracy, and speed. These tradeoff situations provide one good reason why no one graphic format is suitable for all purposes. Of course, there can be good methods (sarisfying solutions) for particular cases." (Michael Macdonald-Ross, "Graphics in Texts", Review of Research in Education Vol. 5, 1977)
"A great virtue of nomograms is that they are usually multivariate, showing relationships among variables in quite complex systems. It is surely helpful to have both an analysis of the underlying equation along with nomogram visualization of the curves generated by the equation. Nomograms show how equations perform. Nomograms remain useful for understanding; their computational use has passed. Computational power is so cheap now, we don’t need look-up tables or nomograms; we can just plug the numbers into the equations and solve." (Edward Tufte, 2002)
"Nomographs are effective ways to graphically calculate various functionally related quantities. Nomographs are really graphical computational devices. They were once used widely in engineering situations when calculating was more laborious than at the present time, and they still can be useful when complex relationships are concerned. In brief, scales are laid out in which the scale intervals and placement of the lines are chosen by well-established procedures. A straight edge can then be used to interconnect independent variables so the corresponding values of dependent variables can be read." (Cheryl Cihon & John K Taylor, "Statistical Techniques for Data Analysis" 2nd. ed., 2005)
"A nomogram not only sheds light on how the effect of one predictor on the probability of response depends on the levels of other factors, but it allows one to quickly estimate the probability of response for individual subjects." (Frank E. Harrell Jr, "Regression Modeling Strategies", 2015)
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