A comparison of software project overruns - flexible versus sequential development models

Flexible software development models, e.g., evolutionary and incremental models, have become increasingly popular. Advocates claim that among the benefits of using these models is reduced overruns, which is one of the main challenges of software project management. This paper describes an in-depth survey of software development projects. The results support the claim that projects which employ a flexible development model experience less effort overruns than do those which employ a sequential model. The reason for the difference is not obvious. We found, for example, no variation in project size, estimation process, or delivered proportion of planned functionality between projects applying different types of development model. When the managers were asked to provide reasons for software overruns and/or estimation accuracy, the largest difference was that more of flexible projects than sequential projects cited good requirement specifications-and good collaboration/communication with clients as contributing to accurate estimates.     

Software challenges: the weakest link in the software engineeringchain

The author compares the performance of software project managers and software technical personnel for five basic activities. Automation does not guarantee success in performing project management functions, but the absence of any automation often correlates with missed or delayed schedules, poor or marginal quality, cost overruns, cancelled projects and the other classical trauma situations of the software industry. The author presents a table of results from a study which gives the percentage of projects applying automation to software management tasks     

Patterns of large software systems: failure and success

Software management consultants have something in common with physicians: both are much more likely to be called in when there are serious problems rather than when everything is fine. Examining large software systems-those in excess of 5000 function points (which is roughly 500000 source code statements in a procedural programming language such as Cobol or Fortran)-that are in trouble is very common for management consultants. Unfortunately, the systems are usually already late, over budget, and showing other signs of acute distress before the study begins. The consultant engagements, therefore, serve to correct the problems and salvage the system-if, indeed, salvaging is possible. The failure or cancellation rate of large software systems is over 20 percent. Of those that are completed, about two thirds experience schedule delays and cost overruns that may approach 100 percent. Roughly the same number are plagued by low reliability and quality problems in the first year of deployment. Yet some large systems finish early, meet their budgets, and have few, if any, quality problems. How do these projects succeed, when so many fail?     

A model for software development effort and cost estimation

Several algorithmic models have been proposed to estimate software costs and other management parameters. Early prediction of completion time is absolutely essential for proper advance planning and aversion of the possible ruin of a project. L.H. Putnam's (1978) SLIM (Software LIfecycle Management) model offers a fairly reliable method that is used extensively to predict project completion times and manpower requirements as the project evolves. However, the nature of the Norden/Rayleigh curve used by Putnam renders it unreliable during the initial phases of the project, especially in projects involving a fast manpower buildup, as is the case with most software projects. In this paper, we propose the use of a model that improves early prediction considerably over the Putnam model. An analytic proof of the model's improved performance is also demonstrated on simulated data     

A model of information systems development project performance

abstract. Performance in information systems development (ISD) projects can be critical to business success. But, while project performance has been the subject of much debate, there has been little empirical research into its determinants. A survey of IS projects in the UK and New Zealand is analysed to test hypotheses concerning performance in terms of both project completion and budget (time-cost) variances. Subsequently, a secondary analysis of the findings is used to build a more complete empirical model of project performance. The paper helps to develop the theory of IS development project performance and also has significant implications for practice. Discussion of the findings highlights the importance of project team dynamics, risk management, senior management support for strategic projects and user participation in ensuring successful IS project performance.     

Impacts of collaborative IS on software development project success in Indian software firms: a service perspective

The collaborative work of team members has become a common occurrence in software development projects. Collaborative information systems (CIS), designed to facilitate and support teamwork, appear critical for software project success. However, the quality and convenience of the services and functions delivered by CIS have not received robust attention in academia. Hence, the current study investigates the role of the CIS service characteristics of service quality and service convenience in teamwork and software development project success using DeLone and McLean’s (D&M) Information System (IS) Success Model as the theoretical framework. This study incorporates the success indicators of teamwork quality, teamwork performance, and project success as measured by software quality and project performance. Data from 153 Indian software companies confirm that collaborative IS services, as well as teamwork quality/performance, are central to software development project success. We believe that the findings of this study will be helpful to project managers of software development firms.     

软件开发项目风险模型分析

随着产业的发展和软件规模的提高,软件项目开发和使用过程中超支、延时、技术缺陷等现象越来越严重。如何在项目实施的过程中进行有效地评估和预防这些风险,以达到识别和消除不利因素对软件开发的影响,都属于软件项目风险管理问题。该文着重讨论了集中软件开发项目风险模型并对其进行了相关分析。     

The influence of selection bias on effort overruns in software development projects

ContextA potentially important, but neglected, reason for effort overruns in software projects is related to selection bias. Selection bias–induced effort overruns occur when proposals are more likely to be accepted and lead to actual projects when based on effort estimates that are too low rather than on realistic estimates or estimates that are too high. The effect of this bias may be particularly important in bidding rounds, but is potentially relevant in all situations where there is effort or cost-based selection between alternatives.ObjectiveTo better understand the relevance and management of selection bias effects in software development contexts.MethodFirst, we present a statistical model illustrating the relation between selection bias in bidding and other contexts and effort overruns. Then, we examine this relation in an experiment with software professionals who estimated and completed a set of development tasks and examine relevant field study evidence. Finally, we use a selection bias scenario to assess awareness of the effect of selection bias among software providers.ResultsThe results from the statistical model and the experiment demonstrated that selection bias is capable of explaining much of the effort overruns. The field evidence was also consistent with a substantial effect of selection bias on effort overruns, although there are alternative explanations for the findings. We found a low awareness of selection bias among the software providers.ConclusionSelection bias is likely to be an important source of effort overruns and should be addressed to reduce problems related to over-optimistic effort estimates.     

软件开发项目风险模型分析

随着产业的发展和软件规模的提高,软件项目开发和使用过程中超支、延时、技术缺陷等现象越来越严重。如何在项目实施的过程中进行有效地评估和预防这些风险,以达到识别和消除不利因素对软件开发的影响,部属于软件项目风险管理问题．该文着重讨论了集中软件开发项目风险模型并对其进行了相关分析。     

Determinants of software quality: A survey of information systems project managers

Software quality is important for the success of any information systems (IS). In this research, we find the determinants of software quality. We used five attributes for software quality: system reliability, maintainability, ease of use, usefulness, and relevance. By surveying 112 IS project managers, we collected data about their perceptions on the software quality attributes and their determinants. We arrived at six factors through exploratory factor analysis. We determined the individual factors that impacted the software quality attributes; for example, reliability is associated with responsiveness of IS department; ease of use is influenced by the capabilities of users and attitude of management; and usefulness is impacted by capabilities of IS department and responsiveness of IS department. We show that organizational factors are more important than technical factors in impacting software quality in IS projects. We provide implications of our research to practice and to future research.     

SYSTEMS DEVELOPMENT AND COST ESTIMATING

Systems development cost estimating is a critical challenge for most IS managers. Inaccurate low estimates result in overruns and can reduce senior management's confidence in IS. Inaccurate high estimates can dissuade corporate management from funding worthwhile IS projects. If cost estimates are entered into a corporate budget, management may be even more concerned about them. The cost-estimating practices in effect at 115 organizations were studied to determine why cost estimating remains such a challenge for IS managers and to devise some guidelines to help IS management arrive at more accurate estimates.     

Using metrics to manage software projects

Five years ago, Bull's Enterprise Servers Operation in Phoenix, Arizona, used a software process that, although understandable, was unpredictable in terms of product quality and delivery schedule. The process generated products with unsatisfactory quality levels and required significant extra effort to avoid major schedule slips. All but the smallest software projects require metrics for effective project management. Hence, as part of a program designed to improve the quality, productivity, and predictability of software development projects, the Phoenix operation launched a series of improvements in 1989. One improvement based software project management on additional software measures. Another introduced an inspection program, since inspection data was essential to project management improvements. Project sizes varied from several thousand lines of code (KLOC) to more than 300 KLOC. The improvement projects enhanced quality and productivity. In essence, Bull now has a process that is repeatable and manageable, and that delivers higher quality products at lower cost. We describe the metrics we selected and implemented, illustrating with examples drawn from several development projects     

Important characteristics of software development team members: an empirical investigation using Repertory Grid

An information system is typically developed by a team of information systems (IS) professionals. Research shows that teams staffed with the right people are more likely to be effective and efficient. There is a paucity of study that examines the important traits of IS professionals in team contexts. The objective of this research is to identify and understand the important characteristics of good team members in software development projects. We applied an established psychological technique (Repertory Grid) to guide our interviews with 21 experienced IS professionals, who have had extensive experience in software development teams. The comprehensive list of important characteristics was analysed qualitatively using open coding method of grounded theory. Fifty‐nine unique characteristics were identified and classified into eight categories. Among them, attitude/motivation, knowledge, interpersonal/communication skills, and working/cognitive ability were perceived by research participants to be the most important categories. Our study provides a context‐specific (i.e. software development team) evaluation of important characteristics of IS professionals. The results have significant implications for IS recruiting, IS training, IS staffing, and IS human resource management. Our study also supplements the research on management of IS development teams.     

Integrating agile software development into stage-gate managed product development

Agile methods have evolved as a bottom-up approach to software development. However, as the software in embedded products is only one part of development projects, agile methods must coexist with project management models typically of the stage-gate type. This paper presents a qualitative case study of two large independent software system projects that have used eXtreme Programming (XP) for software development within contexts of stage-gate project management models. The study is comprised of open ended interviews with managers as well as practitioners, followed by a structured, fully traceable, qualitative analysis. We conclude that it is possible to integrate XP in a gate model context. Key issues for success are the interfaces towards the agile subproject and management attitudes towards the agile approach. Editor: Marvin Zelkowitz     

An Examination of Determinants of Software Testing and Project Management Effort

Software estimation research has primarily focused on software effort involved in direct software development. As more and more organizations buy instead of building software, more effort is spent on software testing and project management. In this empirical study, the effect of program duration, computer platform, and software development tool (SDT) on program testing effort and project management effort is studied. The study results point to program duration and software tool as significant determinants of testing and management effort. Computer platform, however, does not have an effect on testing and management effort. Furthermore, the mean testing effort for third generation (3G) development environment was significantly higher than the mean testing effort for fourth generation (4G) environments that used IDE. In addition, the management effort for 4G environment projects without the use of IDE was lower than nonprogramming report generation projects.     

Understanding the implementation of software process improvement innovations in software organizations

Abstract. The development of software is a complex task frequently resulting in unfinished projects, project overruns and system failures. Software process improvement (SPI) approaches have been promoted as a promising remedy for this situation. The organizational implementation of such approaches is a crucial issue and attempts to introduce SPI into software organizations often fail. This paper presents a framework to understand, and subsequently successfully perform, the implementation of SPI innovations in software organizations. The framework consists of three perspectives on innovation: an individualist, a structuralist and an interactive process perspective. Applied to SPI, they emphasize different aspects of implementing SPI innovations. While the first focuses on leadership, champions and change agents, the second focuses on organization size, departmental and task differentiation and complexity, and the third perspective views the contents of the innovation, the social context and process of the implementation as related in an interactive process. We demonstrate the framework's applicability through two cases. We show that the three perspectives supplement each other and together provide a deeper understanding of the implementation process. Such understanding is crucial for the successful uptake of SPI approaches in software organizations.     

A statistical analysis of the effects of Scrum and Kanban on software development projects

Traditionally, software development processes have relied on the use of the “Waterfall” and “Vee” models. Later, Agile methodologies were used to handle the challenges of managing complex projects during the development phase. Agile methodologies are a group of incremental and iterative methods that are more effective, and have been used in project management. Kanban and Scrum are two powerful Agile project management approaches in software development. The objective of Scrum and Kanban is achieved by optimizing the development process by identifying the tasks, managing time more effectively, and setting-up teams. A review of the literature reveals that there is a lack of statistical evidence to conclude which methodology is more effective in dealing with the traditional project management factors of budget handling, risk control, quality of the project, available resources, having clear project scope, and schedule handling. This research statistically compares the effectiveness of the Scrum and Kanban methods in terms of their effects on the project management factors for software development projects. Numerical analysis is performed based on survey responses from those with experience in the Scrum and Kanban methods. Results suggest that both Scrum and Kanban lead to the development of successful projects, and that the Kanban method can be better than the Scrum method in terms of managing project schedule.     

An empirical analysis of the impact of software development problem factors on software maintainability

Many problem factors in the software development phase affect the maintainability of the delivered software systems. Therefore, understanding software development problem factors can help in not only reducing the incidence of project failure but can also ensure software maintainability. This study focuses on those software development problem factors which may possibly affect software maintainability. Twenty-five problem factors were classified into five dimensions; a questionnaire was designed and 137 software projects were surveyed. A K-means cluster analysis was performed to classify the projects into three groups of low, medium and high maintainability projects. For projects which had a higher level of severity of problem factors, the influence on software maintainability becomes more obvious. The influence of software process improvement (SPI) on project problems and the associated software maintainability was also examined in this study. Results suggest that SPI can help reduce the level of severity of the documentation quality and process management problems, and is only likely to enhance software maintainability to a medium level. Finally, the top 10 list of higher-severity software development problem factors was identified, and implications were discussed.     

Obsolete software requirements

ContextCoping with rapid requirements change is crucial for staying competitive in the software business. Frequently changing customer needs and fierce competition are typical drivers of rapid requirements evolution resulting in requirements obsolescence even before project completion.ObjectiveAlthough the obsolete requirements phenomenon and the implications of not addressing them are known, there is a lack of empirical research dedicated to understanding the nature of obsolete software requirements and their role in requirements management.MethodIn this paper, we report results from an empirical investigation with 219 respondents aimed at investigating the phenomenon of obsolete software requirements.ResultsOur results contain, but are not limited to, defining the phenomenon of obsolete software requirements, investigating how they are handled in industry today and their potential impact.ConclusionWe conclude that obsolete software requirements constitute a significant challenge for companies developing software intensive products, in particular in large projects, and that companies rarely have processes for handling obsolete software requirements. Further, our results call for future research in creating automated methods for obsolete software requirements identification and management, methods that could enable efficient obsolete software requirements management in large projects.