Understanding of Class Diagrams Based on Cognitive Linguistics and Functional Dependency

This paper demonstrates that the structure of a class diagram reflects the cognitive structure of English based on cognitive linguistics. Native English speaking students of software engineering are expected to easily utilize class diagrams because no impedance mismatch exists between their mother language and class diagrams. On the other hand, since the cognitive structures of Japanese are quite different, class diagrams are hard to understand for Japanese students of software engineering. To overcome this impedance mismatch, this paper argues that Japanese students must understand the correspondence between seven English sentence patterns and class diagrams. The cognitive view shows that Is-a and Has-a relationships are necessary and sufficient as specially prepared relationships. Also, this paper clarifies that functional dependency is an important view for class diagrams. Our proposed cognitive linguistics and functional dependency views result in essential and applicative understanding of class diagrams.