Page:Mental Traits of Sex.djvu/18

4 available for any problem is limited, the practical question to be decided is Given a limited amount of time, which of the two modes of procedure mentioned is more likely to yield valuable results? Accuracy of measurement seemed an indispensable requirement for such a study as the present one. Any reliable determination of a threshold or a discriminative sensibility requires a somewhat extended series of experiments. With subjects untrained in psychological experiments as most of these were it is essential to take a large enough series of measurements to give some assurance that the results represent a characteristic reaction, and not haphazard answers. In so simple a test as that of dermal two-point discriminations the first few judgments are very likely to be little more than guesses. In a series of rapid tests like those employed at Columbia University (82) the subject is given only five stimulations with the æsthesiometer. The points are kept a fixed distance apart and the subject is given both one- and two-point stimulations in his series of five. It seems improbable that the results of such a test on unpracticed subjects mean anything more than random answers. The Columbia experiments on a large number of students failed to reveal any difference of sex in the fineness of two-point discriminations, while the present accurate measurement of fifty subjects shows a clear difference.

The series of tests employed in this investigation required from fifteen to twenty hours of time from each subject. The hours were arranged from one sitting to the next according to the convenience of the subject. It was not possible to have the hours for any one test constant for all subjects, since the