Don't become a statistic-take control of your software projects and plan for success! Success in all types of organization depends increasingly on the development of customized software solutions, yet more than half of software projects now in the works will exceed both their schedules and their budgets by more than 50%. While some types of overruns remain unpredictable, most can be avoided by sound modeling. COCOMO II provides you with a thorough rework of the classic COCOMO model to address modern software processes and construction techniques along with representative examples of applying the models to key software decision situations. It was calibrated and validated using innovative statistical techniques to fit both expert judgment and 161 carefully collected project data points. The book also introduces emerging COCOMO II extensions for cost and schedule estimation of COTS integration and rapid development. You'll also: bull; Learn firsthand from knowledgeable authors-over 100 person-years of software cost estimation experience Make better software decisions by exploring their cost implications Use the cost and schedule estimates to better plan and control your projects and manage your risks Get started now with the software on the accompanying CD Keep up to date with the authors' Web site Software engineers, managers, and students will all find Software Cost Estimation with COCOMO II an invaluable guide to developing and managing successful software projects on time and under budget. About the CD-ROM The accompanying CD-ROM includes a current copy of COCOMO II, along with demonstration versions of three commercial COCOMO II packages and an extensive documentation suite. All examples from the book are provided live, so you can work them hands on, along with the reading.

Preface "We are becoming a software company" is an increasingly repeated phrase in organizations as diverse as finance, transportation, aerospace, electronics, and manufacturing firms. Competitive advantage increasingly depends on developing software for smart, tailorable products and services, and on the ability to develop and adapt these products and services more rapidly than competitors' adaptation times. These trends highlight the need for strong capabilities to accurately estimate software cost and schedules, and to support tradeoff, risk, sensitivity, and business case analyses for software decisions. Concurrently, a new generation of software processes and products is changing the way organizations develop software. These new approaches--evolutionary, risk-driven, and collaborative software processes; fourth-generation languages and application generators; commercial off-the-shelf (COTS) and reuse-driven software approaches; fast-track software development approaches; software process maturity initiatives--lead to significant benefits in terms of improved software quality and reduced software cost, risk, and cycle time. However, although some of the existing software cost models have initiatives addressing aspects of these issues, these new approaches have not to date been strongly matched by complementary new models for estimating software costs and schedules. This makes it difficult for organizations to conduct effective planning, analysis, and control of projects using the new approaches. These concerns have led the authors of this book to formulate a new version of the Constructive Cost Model (COCOMO) for software effort, cost and schedule estimation. The original COCOMO 81 Boehm 1981 and its specialized Ada COCOMO successor Boehm and Royce 1989 were reasonably well matched to the classes of software projects that they modeled: largely custom, built-to-specification software Miyazaki and Mori 1985; Goudy 1987. Although Ada COCOMO added a capability for estimating the costs and schedules for incremental software development, COCOMO 81 encountered increasing difficulty in estimating the costs of software created via spiral or evolutionary development models, or of software developed largely via commercial off-the-shelf (COTS) applications-composition capabilities. Software Estimation State of the Practice A number of commercial software estimation models continue to pass the market test for value added to users. And quite a few organizations do a good job of software project planning, estimating, and control. However, a very large number of organizations do not: in the 1995 Standish Group study, over 53% of the software projects were overrun by more than 50% in both budget and schedule Standish 1995. Some recent collections of software failure case studies provide more detail on the reasons for such overruns. Table P1 summarizes the results from six such projects. The first three are from Flowers 1996; the second three are from Glass 1998. Model Clashes and MBASE We have analyzed the projects in Table P1, and have found that many of their problems result from model clashes Boehm-Port 1999b. Model clashes involve incompatibilities among the primary models being used to define and manage the project. These include product models (requirements, architecture, design, etc.); process models (waterfall, spiral, maturity models, etc.); property models (cost, schedule, performance, etc.), and success models (business case, stakeholder win-win, IKIWISI: I'll know it when I see it, etc.). Table P1Software Overrun Case Studies First; Last Estimate Project Cost ($M) Schedule (Months) Status at Completion PROMS (Royalty collection) 12; 21+ 22; 46 Cancelled, Month 28