2887	 A Study of Errors Error-Proneness and Error Diagnosis in Cobol	 This paper provides data on Cobol error frequency for correction of errors in student-oriented compilers improvement of teaching and changes in programming language. Cobol was studied because of economic importance widespread usage possible error-including design and lack of research. The types of errors were identified in a pilot study then using the error types found errors were classified in runs of Cobol students. Error density was high percent of the types contained percent of the total frequency which implies high potential effectiveness for software based correction of Cobol. Surprisingly only four high-frequency errors were error-prone which implies minimal error inducing design. percent of Cobol misspellings were classifiable in the four error categories of previous researchers which implies that Cobol misspellings are correctable by existent algorithms. Reserved word usage was not error-prone which implies minimal interference with usage of reserved words. Over percent of error diagnosis was found to be inaccurate. Such feedback is not optimal for users particularly for the learning user of Cobol. errors in programming error correction Cobol programming language errors error analysis diagnostics error-proneness error frequency spelling errors syntactic errors learning of programming teaching of programming
