Software Metrics
- 2. Why Measure Software Software projects are notorious for running over schedule and budget and having quality problems to boot Software measurement lets you quantify your schedule and budget performance, work effort, product size, product quality, and project status
- 3. What to Measure You can measure many aspects of your software products, projects, and processes The trick is to select a small and balanced set of metrics that will help your organization track progress toward its goals Goal-question-metric (GQM) is an effective technique for selecting appropriate metrics to meet your needs
- 4. Goal-question-metric (GQM) With GQM, you begin by selecting a few project or organizational goals. State the goals to be as quantitative and measurable as you can. They might include targets such as the following: Reduce maintenance costs by 50 percent within one year. Improve schedule estimation accuracy to within 10 percent of actuals. Reduce system testing time by three weeks on the next project. Reduce the average time to close a defect by 40 percent within three months.
- 5. Creating a Measurement Culture Fear is often a software practitioner’s first reaction to a new metrics program People are afraid the data will be used against them, that it will take too much time to collect and analyze the data, or that the team will fixate on getting the numbers right rather than on building good software Creating a software measurement culture and overcoming such resistance will take diligent, congruent steering by managers who are committed to measurement and sensitive to these concerns
- 6. Make It a Habit Software measurement need not consume a great deal of time Commercial tools are available for measuring code size in many programming languages Activities such as daily time tracking constitute a habit each developer gets into, not a burden Develop simple tracking forms, scripts, and Web-based reporting tools to reduce the overhead of collecting and reporting the data Use spreadsheets and charts to track and report on the accumulated data at regular intervals
- 7. Tips for Metrics Success Start Small: Because developing your measurement culture and infrastructure will take time, consider using GQM to first select a basic set of initial metrics. Once your team becomes used to the idea of measurement and you’ve gained some momentum, you can introduce new metrics that will provide the additional information you need to manage your projects and organization effectively. Explain Why: Be prepared to explain to a skeptical team why you wish to measure the items you choose. They have the right to understand your motivations and why you think the data will be valuable. Share the Data: Your team will be more motivated to participate in the measurement program if you tell them how you’ve used the data