Feeds

The black art of software estimation

How long is a piece of string? The question answered

  • alert
  • submit to reddit

Combat fraud and increase customer satisfaction

Software EstimationBook review Steve McConnell of Code Complete fame, is not joking when he describes software estimation as a black art, though even then he's being generous.

An art, even a black one, implies both skill and accomplishment. For most developers software estimation is one part blind panic and the other self-defence. Why should this be? And what can be done to alter the situation? These are the types of questions McConnell sets out to answer in Software Estimation.

In setting out to define what software estimation is, McConnell begins to tease out some of those answers, in particular the difference between an estimate and a target. You would think that these terms are clear and well differentiated, but in practice there's very often confusion between the two. When a manager asks for an estimate, often he or she is really looking to set a target. And when a developer responds, he or she knows that the manager is really after a target and so makes a political response rather than offering an honest estimate.

Defining terms is all well and good - it certainly helps to clarify things - but the aim of the Software Estimation is more than to offer a useful set of semantics. To this end, McConnell looks at both the science and the art of estimation, and he suggests a mix of calculation and judgement is needed to create estimates that are both useful and accurate to developers and managers alike.

As with Code Complete, McConnell has done a lot of homework. His job here is to popularise work going on in research labs and universities on the best estimation techniques available. Many of these techniques are really only applicable to larger software development organisations and projects. They depend, to a great extent, on having access to historical data and systems for accurately recording existing project details. For the science end of the estimation spectrum, counting, computing, and making judgements are key.

However, it's not just the big development shops who stand to gain from this book. If the range of "scientific" software estimation techniques are expensive, there are other techniques that are less science and more art. These range from sound advice - never give off the cuff estimates, try to use ranges in your estimates rather than a single point - to discussion of the "cone of uncertainty", which shows that there is greater variability earlier in a project, and therefore estimates are less likely to be accurate.

While not as immediate as Code Complete, Software Estimation is still an interesting and well-written book. McConnell has the knack of making complex research accessible to practitioners, and most software developers will key in to the issues he describes.

Will reading this book make your estimates more accurate? Well, it will certainly give you a lot more ammunition and some new techniques to try out. At the very least, there's plenty of food for thought.

Software Estimation: Demystifying the Black Art

Verdict: Well-written and interesting

Author: Steve McConnell

Publisher: Microsoft Press

ISBN: 0735605351

Buy this book at Cash 'n' Carrion.

Combat fraud and increase customer satisfaction

More from The Register

next story
OpenBSD founder wants to bin buggy OpenSSL library, launches fork
One Heartbleed vuln was too many for Theo de Raadt
Got Windows 8.1 Update yet? Get ready for YET ANOTHER ONE – rumor
Leaker claims big release due this fall as Microsoft herds us into the CLOUD
This time it's 'Personal': new Office 365 sub covers just two devices
Redmond also brings Office into Google's back yard
Ubuntu 14.04 LTS: Great changes, but sssh don't mention the...
Why HELLO Amazon! You weren't here last time
Patch iOS, OS X now: PDFs, JPEGs, URLs, web pages can pwn your kit
Plus: iThings and desktops at risk of NEW SSL attack flaw
Next Windows obsolescence panic is 450 days from … NOW!
The clock is ticking louder for Windows Server 2003 R2 users
Batten down the hatches, Ubuntu 14.04 LTS due in TWO DAYS
Admins dab straining server brows in advance of Trusty Tahr's long-term support landing
Red Hat to ship RHEL 7 release candidate with a taste of container tech
Grab 'near-final' version of next Enterprise Linux next week
Apple inaugurates free OS X beta program for world+dog
Prerelease software now open to anyone, not just developers – as long as you keep quiet
prev story

Whitepapers

Mobile application security study
Download this report to see the alarming realities regarding the sheer number of applications vulnerable to attack, as well as the most common and easily addressable vulnerability errors.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.