Skill hierarchy revised by SEM and additional skills

In this paper, we reexamine the Lopez´s skill hierarchy by using structural equation modeling (SEM), by which we can explicitly see the relationship between variables. We also introduce two more skills, a skill to modify a given piece of code to satisfy a given specification and a skill to write code from scratch to satisfy a given specification. The analysis shows that these additional skills are useful. The path diagram (model) with the highest fitness measures suggests an effective order of training and pivotal roles of the Tracing2 and Explain skills in training.