Page:Graphic methods for presenting facts (1914).djvu/225

 Notice that in the upper portion of the chart the line shifts across the equality line, showing that some of the more brilliant girls obtain higher marks in arithmetic than they do in English. The lower portion of the chart shows that the larger number of girls get considerably better marks in English than in arithmetic, and that this is a general condition to be expected. In the case of those girls who do well in both English and arithmetic, there seems to be improved facility in the field of arithmetic.

Data of W. Garnett in the Journal of the Royal Statistical Society, 1910

Fig. 166. Examination Marks Obtained by 9,396 School Girls in England

Each girl is represented by one dot showing to scale the grade in English and the grade in arithmetic. The dots are arranged uniformly inside of squares formed by co-ordinate lines spaced ten units apart in the scales for marks. The straight diagonal line drawn from zero shows equal ability in the two studies. The heavy wavy line is drawn through points having an equal number of girls represented on either side of the line, and its position proves that girls have much more ability in English than in arithmetic.