Inter-rater correlation on scoring open-ended questions in science education

This research aims to investigate inter-rater correlation on scoring the open-ended questions in science education in case of using an answer key and the difference among the average scores given by science teachers. For data collection, an assesment tool consisting of six open-ended questions and an answer key to score the assessment tool were prepared. The open-ended questions were applied to 28 students studying in the 7th grade of a middle school in Eastern Anatolia. The answers given to the questions were scored by 12 Science teachers working in Ağrı and its districts. It was tried to determine whether there was a significant relationship and difference among the points given by the raters and also the difference among the average scores they gave. The scores given by the raters were analyzed and the correlation coefficients among the raters were obtained. This research was conducted through a "Case Study Method" within the scope of "Descriptive Research". For each application, the scores of different teachers were compared with each other. The average scores of the raters were analyzed for the difference among the mean scores of the different teachers. In conclusion, for each open-ended question, a positive and high correlation was determined among the raters. However, there are significant differences among the averages of the scores.