Safe and simple software cost analysis - IEEE Software

S imple software cost-analysis methods are readily available, but they aren’t always safe. The simplest method is to base your cost estimate on the typical costs or productivity rates of your previous projects. That approach will work well if your new project doesn’t have any cost-critical differences from those previous projects. But it won’t be safe if some critical cost driver has degraded. Simple history-based software cost-analysis methods would be safer if you could identify which cost driver factors were likely to cause critical cost differences and estimate how much cost difference would result if a critical cost driver changed by a given degree. In this column, I’ll provide a safe and simple method for doing both of these by using some recently published cost estimating relationships (Software Cost Estimation with COCOMO II, by Barry Boehm et al., Prentice Hall, 2000). COCOMO II is an updated and recalibrated version of the Constructive Cost Model (COCOMO) originally published in Software Engineering Economics (by Barry Boehm, Prentice Hall, 1981). I’ll also show how the COCOMO II cost drivers let you perform cost sensitivity and trade-off analyses, and discuss how you can use similar methods with other software cost-estimation models. COCOMO II Productivity Ranges