Supporting Process Improvement using Method Increments

With the research described in this dissertation, we aim to shed light on the characteristics of process improvement efforts by looking at their evolution (how to change?) rather than their content (what to change?). This research is triggered by three main propositions, derived from earlier work: (i) methods can be dissected into method fragments; (ii) the process of method evolution can be dissected into method increments; and (iii) method increments can be used to guide method construction. These assumptions have not been thoroughly tested and explored yet. Especially the method increment concept is not well understood. The research reported in this dissertation tries to fill this gap by answering the following question: How can method increments be used to support process improvement efforts? The dissertation provides an answer to this question through three parts. The first part describes two studies that investigate the characteristics of process improvement efforts, by looking at such efforts in the domain of agile software development. One study describes a case study, resulting in a method description for agile software product management. While this relates more to the what than the how of process improvement, it provides preliminary insights on the structure of process improvement efforts. We expand upon this insight in the second chapter, in which we analyze and compare the introduction of Scrum at four case companies. The results show a variety of approaches, with heterogeneous effects on effectiveness. In the second part of the dissertation, we develop a better understanding of the notion of method increment. The first chapter expands on the topic of knowledge gathering related to method increments by providing a detailed description and evaluation of a method increment template. In the second chapter of this part, we propose and evaluate a formalization of the process-deliverable diagram, specifically aimed at describing method changes, along with a planning framework and process for generating plans that comply with different types of constraints. In the third part, we describe the design, realization, and evaluation of a knowledge management system that supports incremental method engineering. This system, the Online Method Engine (OME), encompasses the dissemination of method knowledge, linked to process assessment, improvement, and enactment. The OME is based firmly upon the results from the first two parts, and demonstrates a potential solution that helps practitioners during process improvement efforts.

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