Notes on Two Multiple-Variable Spot Maps

Abstract

IN THE field of sociology, perhaps one of the most useful devices for the graphic presentation of facts is the cartogram or statistical map. Recently there has been an increasing emphasis on the ecological and statistical phases of social analysis. This development has given the map much greater significance and utility in the methodology of sociology. The cartogram, like many other forms of diagrams, is essentially an illustrative' method by which several sets of facts,-geographical, ecological, magnitudinal, or typical,-are shown simultaneously in such a visually and statistically logical way that the mind can comprehend these facts and their relationships with a minimum amount of time and effort. Although by no means clearly distinct from one another, there are, from a sociological point of view, five types of cartograms: (i) the social base map, (z) the cross-hatched map, (3) the colored map, (4) the spot-map, and (5) a composite of two or more of the preceding types.2 This discussion will be devoted entirely to the spot-map. Notwithstanding that the spot-map is characteristically quite elementary, if not, as some critics say, superficial, yet it can be delineated so that it shows several variables at once with specificity, accuracy, and clarity. The purpose of this paper is to discuss two multiplevariable spot-maps as typical examples of this method of presenting statistical and ecological data graphically. 1 Charts are often classified according to purpose; viZ., illustrative, analytical, and computative. Vide: Jerome, Harry, Statistical Method (Harper and Brothers, London and New York, 192X4), pp. 5o-5i and pp. 70-71; also cf. Goldenweiser, E. A., Classification and Limitations of Statistical Graphics, Pub. Am. Statis. Assn., 15: 2.o5-2og. It should not be overlooked, however, that the cartogram has many possibilities as a method of social analysis, and, ultimately, may supersede in importance the mere illustrative type. It is hoped that the two multiple-variable spot-maps as presented herein, approach the analytical phase of presentation. If, for cxample, the Suicide Map presented below, is colligatcd with other maps, as it will be in the study of which it is a part, such as population density, sex distribution, indices of disorganization, indusErial, commcrcial and residential districts, etc., a very clear analysis of communal structure and social organization can be brought into graphic relief. For a very good discussion of the value and feasibility of the cartogram as a method of social analysis, Vide: Young Erle F., Social Base Map, J. Ap. Sociol., (JanuaryFebruary, I 92.5.) ix: 2.o2.-6. 2 Cf. Secrist, Horace, An Introduction to Statistical Methods (Macmillan, New York, Rev. Ed., 192.5), p. 2.o; also vide, Young, Erle F., op. cit.