Ideas para el uso de las caras de Chernoff en la cartografía escolar

Abstract

In 1973 Hermann Chernoff (who at present is Professor Emeritus of Applied Mathematics, in the Department of Statistics at Harvard University) created originally this method for the graphic representation of statistical data, to represent specific multivariate data using only one symbol (a human face) changing its features. Only four years later, from 1977 the Chernoff faces began to be introduced also to cartography abroad, using the human faces to represent data on a map following the traditional methods of thematic representation. The first and more famous (today considered a classic) example is the map entitled “Life in Los Angeles, 1970”, made by Eugene Turner from the Geography Dept. at the California State University in 1977. Along the last two decades new maps were made taking advantage of the technological development represented by the daily use of personal computers to complete different map tasks, mainly during the making of different types of thematic maps. These solutions are characterized not only by6 Bol. geogr., Maringa, v. 28, n. 1, p. 5-15, 2010the use of the original method, but also by its new variations. At present, the processing of data using Chernoff faces is included in a common way in statistical software (e.g. Statistica, S-PLUS or Systat), but not in software related to cartography or/and GIS, which can be one of the reasons because the method has not been used more widely on maps. Present work includes some examples about international research on this theme and the general use of this method on maps (DORLING, 1991; FABRIKANT, 2004; NELSON, 1997, 2007). Some of the practical experiences acquired by the author are also presented: the majority of them were obtained during the theoretical and practical teaching of this method for MSc students on Cartography at Eotvos Lorand University. These experiences are illustrated by some thematic maps made by the students using the original Chernoff faces and it’s adaptation to represent data on maps. Some new proposals about the possible future use of the Chernoff faces in school cartography (mainly on thematic maps in school atlases) are also presented, more exactly how to adapt the original Chernoff method for its use on maps made for pupils in Elementary and Secondary Schools, modifying the original method in interest of improving the map reading. At present, these questions are studied within an international project counting with the participation of Argentine and Hungarian specialists. The main task of this bilateral project is the organization of a survey about the cartographic use of Chernoff faces in both countries, applied for pupils in Elementary and Secondary Schools.