Abstract
In this paper, we consider to grasp ceiterion-referenced evaluation structure of a practical subject by a function on the basis of teacher's subjectivity. A membership function in the fuzzy theory is used as its function. Reached levels are guessed from freely written criticism for some evaluation items. The membership function corresponding to the reached level is found by using fuzzy reasoning. The center of gravity in area of the membership function is computed for one of evaluation items. The work's evaluation is the value divided the sum of the values in the centers of gravity by the number of the evaluation items written in the criticism. Evaluation values are computed by changing the membership functions. We compute an average of absolute subtraction between the ten-point ratings and the fuzzy evaluation for works. Teacher's evaluation structure is presumed by the membership function with the minimal average. Work's evaluation is obtained using the membership function. This is called fuzzy evaluation method. We asked teacher's questionnaires about the criticism and ten-point ratings for real calligraphy works of four pupils. The fuzzy evaluation obtained using the questionnaires shows to be exactly similar to the ten-point rating.
