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 of sufficient number to permit the formation of any general laws. Thus for Fig. 143 we are not justified in saying that all college women marry at the particular ages indicated by this chart. The number of women taken into consideration for the preparation of the chart was not sufficient to allow any final conclusion, certainly not to justify any general statement that college women are less likely to marry at the age of twenty-six than at either twenty-five or twenty-seven.

United States Statistical Atlas, 1900 Census

Fig. 144. Conjugal Condition of the Population of the United States in 1900 in Proportions of the Total Number of Each Age Group

This chart was printed in color in the Statistical Atlas. Here shading is used instead of color. The arrangement to the right and left of a zero line at the center makes visual comparison difficult between the data for males and females. Note the contrasts between the upper and lower charts. Compare the upper chart with Fig. 145

In biological work the number of observations taken is ordinarily sufficient to permit drawing a smooth curve to represent the general law, after a chart drawn with numerous straight lines has been made by the method used in Fig. 143. It would not be desirable to draw a smooth curve in the case of Fig. 143, as the smooth curve would be misleading because of the small number of observations made. For most business problems, and in many problems actually in the field of statistics, the laws which affect frequency are so indefinite