RATING SCALES 175
sidered a point in favor of a rating scale. With several
judges rating the same men, the scale which shows the
highest correlation between obviously unrelated abilities
may be considered the weakest.
A seventh criterion, mentioned by Plant (140), is as follows:
 Present a person with a list of his acquaintances, and
with a set of ratings on one of the men in the list. Ask him
to indicate which of the men is the one to whom the ratings
apply. That scale is best which yields the most easily identified
 ratings.
Non-statistical points to be kept in mind when choosing
a rating scale are simplicity, brevity, convenience, clearness
of directions, time required for completing the rating, agreeableness
 of the rating task, universality of the scale, and
ease of scoring.
The graphic rating method is at present the most popular.
 By the use of this method judges agree closely among
themselves in rating the same men, and judgments are consistent
 when repeated after a long time interval. It is simple
and easy to grasp, easily filled out and scored, frees the
rater from direct quantitative terms, and makes the degree
of the ability concrete. Finally, it has been found to be
more interesting to use, as well as convenient and reliable.
HOW TO MAKE A GRAPHIC RATING SCALE
The tendency in the evolution of graphic rating scales has
been toward the adoption of the practices recommended below.
 The superiority of these practices has not in all cases
been demonstrated experimentally, and much research is
still needed in order to develop the most reliable as well as
the most convenient forms of scales.
It will help the rater if each scale is prefaced by a description
 of the ability in question.
It is important that this description be in terms of behavior
 rather than of mental qualities. The more con-TRE