The importance of software project estimation
Accurate estimations provide the time, cost, effort and resources required to successfully implement a software project. They ensure that: expectations of project stakeholders are satisfied, project timelines and budgets are met. Estimations should include contingencies for: scope creep, unexpected events (e.g. Covid-19), employee attrition, overruns in budget and timing.
The IT industry has slowly improved estimation maturity resulting in better accuracy. Many organizations still rely solely on human judgement (expert estimation), which usually results in subjective estimates and therefore (huge) project overruns.
To improve maturity, organizations must adopt functional size measurement and parametric models for software cost estimation, using relevant historical data, like the ISBSG repository. Historical project data provides useful guidelines for estimations. It can be used as a benchmark throughout the project’s lifecycle.
The International Cost Estimation and Analysis Association (ICEAA) and NESMA created Special Interest Group ICEAA – Software. This is to promote the Software Cost Estimation Body of Knowledge (CEBoK-S) and Software Cost Estimation Certification (SCEC). ISBSG data supports Cost Estimation with its attributes (e.g. size, year, industry, application type, activity effort, duration, quality, defects).
An example of how ISBSG data helps with cost estimating is shown in the short paper, Software Cost Estimate for a Large Trading Company or visit the ISBSG Data Subscriptions web page.
