Joachim Karlsson

Software requirements prioritizing

The importance of candidate software requirements can vary by orders of magnitude, yet most software providers do not have accurate and efficient means for selecting among them. The paper describes a case study at Ericsson Radio Systems AB of two techniques for software requirements prioritizing as a means for determining the importance of candidate requirements, a pairwise comparison technique and a numeral assignment technique. The results from the case study indicate that the pairwise comparison technique is an efficient informative and accurate means for finding the candidate requirements importance. We therefore recommend the pairwise comparison technique for software requirements prioritizing. At Ericsson we have extended its use in other development projects.

Improved practical support for large-scale requirements prioritising

An efficient, accurate and practical process for prioritising requirements is of great importance in commercial software developments. This article improves an existing cost-value approach in which stakeholders compare all unique pairs of candidate requirements according to their value and their cost of implementation. Techniques for reducing the required number of comparisons are suggested, thus making the process more efficient. An initial approach for managing requirements interdependencies is proposed. A support tool for the improved process has been developed to make the process more practical in commercial developments. The improved process and its support tool have been applied and evaluated in an industrial project at Ericsson Radio Systems AB. The results indicate a pressing need for mature processes for prioritising requirements, and the work presented here is an important step in that direction.

A Feasibility Study of Automated Natural Language Requirements Analysis in Market-Driven Development

In market-driven software development there is a strong need for support to handle congestion in the requirements engineering process, which may occur as the demand for short time-to-market is combined with a rapid arrival of new requirements from many different sources. Automated analysis of the continuous flow of incoming requirements provides an opportunity to increase the efficiency of the requirements engineering process. This paper presents empirical evaluations of the benefit of automated similarity analysis of textual requirements, where existing information retrieval techniques are used to statistically measure requirements similarity. The results show that automated analysis of similarity among textual requirements is a promising technique that may provide effective support in identifying relationships between requirements.

Managing software requirements using quality function deployment

In this article we describe and discuss QFD (quality function deployment) as a framework for managing software requirements. Experiences were gained while participating as researchers in a commercial large-scale software telecommunications project at Ericsson Radio Systems AB. We found that prerequisites for succeeding with QFD include having visible customers and users, forming a cross-functional team adequately trained in QFD, and allowing adequate time for its first application. Advantages of using QFD are: better focus on customers and users, an effective means of prioritizing and communicating software requirements; and managing non-functional requirements. Issues not fully supported by QFD include adequate abstractions levels in describing requirements, handling temporal relations between requirements and initiating the use of QFD for a new development project.

Supporting the selection of software requirements

The choice of candidate requirements for implementation is a primary determinant of customer satisfaction. It is argued that a set of requirements should be chosen which reflects both the importance and the estimated cost of each candidate requirement. A contribution-based method is proposed which determines importance and estimates cost and industrial experience in applying this method is reported. The results indicate that the contribution of candidate requirements can vary by orders of magnitude. By applying the method, software managers are in a position to select requirements for implementation based on each candidate requirements contribution.

A usability-oriented approach to requirements engineering

We describe and propose a usability-oriented approach to requirements engineering, the Delta method. We suggest that by focusing primarily on the tasks that the users are supposed to accomplish using a system, rather than the functionality of the system, functional requirements are elicited in a natural way and in their right context. The Delta method was developed in collaboration with a consultancy firm and validated in a commercial project. The components of the Delta method are outlined and discussed. The method is described further in a case study, and the results of this industrial application are reported.

Prioritizing software requirements in an industrial setting

The planning of additional features and releases is a major concern for commercial software companies. We describe how, in collaboration with Ericsson Radio Systems, we developed and tested an industrially useful approach to software requirements prioritization.