Thesis submitted

Last Friday, after 5 long years, I have finally submitted my PhD thesis. It was quite a relief, more or less as if an elephant was taken off my back.

An English title for my thesis would be Structural Complexity Characterization in Software Systems. Here is an abstract:

This thesis proposes a theory to characterize structural complexity in software systems. This theory aims to identify (i) the contribution of several factors to the structural complexity variation and (ii) the effects of structural complexity in software projects. Possible factors in the structural complexity variation include: human factors, such as general experience of the developers and their familiarity with the different parts of the system; factors related to the changes performed on the system, such as size variation and change diffusion; and organizational factors, such as the maturity of the software development process and the communication structure of the project. Effects of structural complexity include higher effort, and consequently higher cost, in software comprehension and maintenance activities.

To test the validity of the proposed theory, four empirical studies were performed, mining data from free software project repositories. We analyzed historical data from changes performed in 13 systems from different application domains and written in different programming languages.

The results of these studies indicated that all the factors studied influenced the structural complexity variation significantly in at least one of the projects, but different projects were influenced by different sets of factors. The models obtained were capable of describing up to 93% of the structural complexity variation in the projects analyzed.

Keywords: Structural Complexity, Software Maintainance, Human factors in Software Engineering, Mining Software Repositories, Theories in Software Engineering, Empirical Software Engineering, Free/Open Source Software Projects.

Those who read Portuguese can check out the actual thesis text as a PDF file.

Most of the studies discussed in the thesis are presented in English in papers I have published during the last years.

My defense is going to be on March 23rd. If you happen to be at Salvador at that day, please feel cordially invited.