User Access in Rearranging Programming Puzzles, Retries and Missing Measured Data

Abstract

An increasing number of studies are using information systems in learning and teaching, and they are introducing the system in actual classes. Many such studies and case studies measure and analyze learners' exercise processes. However, there are few reports of such cases that analyze access to learning systems or evaluate missing data in the analysis. When we experienced performance problems with a learning system we developed and operated, the maximum number of requests per second to access a question page reached 33 requests per second, and some of the data in the user operation logs we were measuring was lost. In that case, the same user accessed the same problem every 0.2 seconds. Since we fixed those problems, no similar performance problems have occurred. We introduced retries to send user operations logs into the database. Subsequently, about 660,000 operation logs were generated during the two-and-a-half years to date, and retries occurred in 0.06% of them. In classes with many retries, missing data also occurred. On the other hand, in the most recent month, 62,000 operation logs were generated, but there were five retries, or 0.008% of them, and 0 missing data. These results will benefit the design and operation of learning and education systems.