Newman’s Error Analysis: Set Material in 7th-Grade Junior High School

Set is one of the main materials contained in the mathematics subject for 7th-grade junior high school in odd semesters. In the set material, there's no formula used, but there are various kinds of notations, symbols, and also diagrams. Basically, some or even most students still face various difficulties in understanding and working on problems in set operations. This study aims to determine the types of errors and the percentage of errors in 7th-grade junior high school's responses to set material test questions using Newman's error analysis procedure. In this study, we used a qualitative descriptive method, while the data processing technique was done by analyzing student answers based on questions that were test instruments. The research subjects were taken from students in the VII-E class at SMP IT Fithrah Insani, which included as many as 22 students. Then the subjects were analyzed, and based on the results of the research, it turned out that there were still errors in solving set questions. The most frequent error made by students is an encoding error of 40.91%. In this error, the student did not write a complete final answer, or even the conclusion of the solution, so that he did not answer the question posed by the problem.