Software testing defects metrics

Taking the cumulative defect counts and test execution rates, the theoretical curve is plotted. This in comparison with the actual values will trigger an early red flag that test processes need to change if the targets are to be reached. More information and image source.

Software undergoes changes — frequent, few, and far between. Changes incorporated have to be monitored to understand their impact on the stability of the existing system. Changes usually induce new defects, reduce application stability, cause timelines to slip, jeopardize quality, etc. Total number of defects that can be attributed to changes.

This could mean making sure defects have proper affected and fix visions attached when they are reported to development. It is a little bit of an effort to categorize these defects as change related and not, but it is worth it.

For example: If ten changes were made on the system and 30 defects were attributable to the changes, then each change ended up injecting three defects and the defect injection rate is 3 per change. Knowing this number will help predict the amount of defects that could be expected per new change.

This allows test teams to strategically use retrospective meetings to understand their capacity to help identify and fix defects coming from new changes.

Odds are that your team right how has set up a whole list of refined classifications for defect reporting. Defect distribution charts are helpful in understanding the distribution and to identify areas to target for maximum defect removal.

By using a histogram, pie or Pareto charts that show where your development and testing efforts should go. Defect distribution by test type-Review, walkthrough, test execution, exploration, etc. A histogram or a pie chart shows an instant visual identification to highly affected areas. But, when there are too many parameters, without patterns that are difficult to discern, you might have to use a Pareto chart. It helps you to quickly find the areas that are most dense the reason for most defects.

When creating a histogram, be sure to organize your data values from High to low or low to high for most impact. You can stop here, but to get more out of your metrics, continue with the next step. Combine the histogram with the distribution of Severity of defects in each cause. This will give you the areas that you should focus on more accurately. So this chart will refine our data and give us a much deeper understanding of where to channel further development and fixing effort.

Defect Distribution Pareto Chart:. You could also create a Pareto chart to find which causes will fix most defects. In many cases, a Pareto chart may not be necessary. However, if there too many causes and the histogram or pie chart is insufficient to show the trends clearly, a Pareto chart can come in handy. Defect distribution at the end of test cycles or at a certain point in test cycles is a snapshot of defect data at that point in time.

It cannot be used to derive conclusions if things are getting better or worse. For example: At a point of time, you will know that are X number of severe bugs. We can see if defects have been increasing, decreasing or are stable over time or over releases. Defect Distribution over time by Cause. What are some of the critical software testing metrics businesses should know? Software testing metrics are quantifiable measures used to determine the progress of the software testing activities.

Typically, they help teams track and monitor the software testing progress, quality, and productivity. The main aim of these testing metrics is to increase the efficiency of the overall software testing process.

These testing metrics help stakeholders make informed decisions about further improvements in the testing process by providing related information. There are many types of software testing metrics but broadly divided into four main types. Broad types of software metrics.

These published metrics are divided into five categories based on their measure, size, complexity, coupling, cohesion, and inheritance factors. These metrics measure the software development. It is vital to measure the number of defects within the code and the time taken to fix them.

There should be more emphasis on the number of defects in the code than the time taken to resolve those defects. Suppose multiple defects are occurring numerous times in the code and required to be fixed multiple times. There are two main categories of testing metrics based on what they measure. The first is test coverage, and the second is defect removal efficiency.

Test coverage metrics measure how many test cases were executed, how many test cases were still left to be completed, what parts of the software were tested, how much percentage of testing still left, etc. Whereas the defect removal efficiency metrics measure how many defects were identified, how many defects were removed, etc. These metrics relate to the project quality and are used to quantify defects, cost, schedule, productivity and estimate various project resources and deliverables.

Project metrics help teams to assess the health of a project and make informed decisions. These metrics reveal how well the project is getting completed as compared to KPIs selected previously. Some characteristics and components of Software Testing Metrics. Risks involved 5. Defects 6. This stage involves the identification of metrics to be used. Once the metrics are identified, parameters are defined and set for evaluating the metrics. In this stage, the need for the metrics is communicated to the testing teams and stakeholders.

The testing teams are also educated about the data points that should be collected for processing the metrics. In this stage, the data is captured and verified by the testing teams. It also involves the calculation of metrics value as per the data captured. In this stage, a formal report with an effective conclusion is developed and shared with the stakeholders. Feedback is collected from the stakeholders regarding what further actions are to be taken up.

Four main categories of software testing metrics. These metrics are used to measure and improve the ability of the software testing process, e. The main aim of these metrics is to improve product quality. It describes the project characteristics such as cost, schedule, productivity, and also measures project efficiency such as how well the project is moving, and whether it is going as per schedule, or is it lagging behind the plan, etc.

It measures the ability and skill levels of software testing teams. Making technical presentations will be a good goal for your testers. It improves their passion and vision for software testing. Also, they can widen their networks and they will be an ambassador of your company and team. At each meetup or conference, they learn new things and they can share their knowledge. You should support your testers to promote their selves and your team, share their knowledge, and become international software testers.

There are several online learning websites available. Thus, you can assign related courses to your team members and monitor them to finish those assigned courses. Also at SeleniumCamp Alper Mermer talked about software testing metrics and he listed those metrics as follows:.

As you have seen and written in this article, metrics are limitless. Using some of them as a KPI may be dangerous. You can use them to see the status of your situation and try to question your system, methodology, deficiencies, for continuous improvement. If you use them as a rewarding or punishing tool, it will create enormous pressure and stress on your team.

Try to use them in the right way and effectively based on your beliefs, philosophy, organizational culture, etc.

Seek first to understand, then act! Create Trust and Love! Help your team! Believe in them! Austin, Measuring and Managing Performance in Organizations.

New York: Dorset House Publishing, I like the approach of focusing on [solution;] appling the well known development and test practices before KPI measurements. Thank you so much Erdem. Your kind comments are very valuable for me. I am happy that you liked the content and the approach. I have used many of these metrics during my professional career. Never have I seen them all in one place. Excellent Job! Onur Hello Onur, thank you for the article. It is very helpful. Onur — in my company we are using Jira and integrated TestRail.

I have been trying to create different types of matrix but did not succeed yet. Juts wondering, are you providing the consulting services? Hi Irina, thank you for your kind comments. Yes, I can help you as much as I can.

I will send you an email from my personal email address. Onur, thank you for the wonderful document, we have been using some of these KPIs for waterfall model and were successful in achieving the goal, now that we are agile I need to modify some of these KPIs to better suit this environment. So some of the KPIs that you have defined are helpful but need some guidance. Hi John, thank you very much. You are right. We should modify KPIs and metrics based on our companies and their cultures.

However, we have to stick with the core principles while modifying them. Thanks for the feedback. AI Expand child menu Expand. Toggle Menu Close.

Search for: Search. Explain the need for metric to stakeholder and testing team Educate the testing team about the data points to need to be captured for processing the metric. Capture and verify the data Calculating the metrics value using the data captured. Develop the report with an effective conclusion Distribute the report to the stakeholder and respective representative Take feedback from stakeholder.

Determination of the information to be followed, a frequency of tracking and the person responsible. The actual test execution per day will be captured by the test manager at the end of the day.

The Test Case execution falls below the goal set, we need to investigate the reason and suggest the improvement measures.