Abstract
This study suggests two types of indices to evaluate individual student's achievement of foreign language abilities between two time points. One, named uniform achievement index, is defined as the ratio of additional score between two time points to the total score range of a test. The second one, named relative achievement index, is defined as the ratio of additional scores between two time points to the remaining score at the base time point to the full score if the score is improved during the given period of time, and if not, is defined as the ratio of the amount of losing scores to the difference of the score at the base time point from the least score of the test. Two indices are both having values between -1 to 1, and easy to interpret. Also, they are eligible to compare scores from different tests at the same time. However, relative achievement index will be more useful to compare student having different base scores because it is consider each student's test score at the base time.
일정기간동안 성취한 개인의 외국어능력 개별성취도지수로 균일성취도지수와 상대성취도지수를 제안하고 그 특성을 비교하였다. 두 지수 모두 -1 ${\sim}$1의값을 가지며 해석이 용이하다. 또한 최고와 최저 점수가 서로 다른 시험의 성취도를 동시에 비교할 수도 있다. 그러나 상태성취도지수는 각 사람의 초기 평가시점의 점수를 고려한다는 점에서 균일성취도지수보다 합리적인 평가지수이다. 본 연구 결과는 각 학생의 현재 능력을 고려하여 성취도를 측정 비교할 뿐 아니라, 서로 다른 종류의 외국어능력시험결과를 동시에 비교할 유용한 지표를 제시한다.