A glance at the photograph taken looking down on this group of men shows that there are more men shorter than the most frequent height than there are men taller. If an ink line were drawn as a smooth curve to represent the outline of the whole group of men, when arranged in rows as shown here, the top of the curve at the end of the longest row would be called the "mode", as it would show the type found most frequently in all the individuals under observation.

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GRAPHIC METHODS

In the following illustrations, curves of this kind will be noticed using the diagrammatic form rather than the actual photographs of a classified group like Fig. 141. In Fig. 141 it is regrettable that the illustration does not show a scale giving for each row the maximum and minimum height of men in that row. Some scheme, of course, was necessary to divide these men up into height classes, but the reader has no way of knowing the limits of height for each class except by referring to the title of the illustration.

Frequency charts are sometimes made for popular illustration by drawing vertical lines to represent the number of individuals found in each class designated by the horizontal scale. Thus, a representation could be made for the data of Fig. 141 by having a horizontal scale to represent heights, and drawing vertical lines to a scale by, which the length of each vertical line or bar would represent the number of individuals of that particular height. The series of bars would then have the same general arrangement as the