It is known that quantitative measures for the reliability of software systems can be derived from software reliability models. And, as such, support the product development process. Over the past four decades, research activities in this area have been performed. As a result, many software reliability models have been proposed. It was shown that, once these models reach a certain level of convergence, it can enable the developer to release the software. And stop software testing accordingly. Criteria to determine the optimal testing time include the number of remaining errors, failure rate, reliability requirements, or total system cost. In this paper we will present our results in predicting the reliability of software for agile testing environments. We seek to model this way of working by extending the Jelinski-Moranda model to a ‘stack’ of feature-specific models, assuming that the bugs are labelled with the feature they belong to. In order to demonstrate the extended model, several prediction results of actual cases will be presented. The questions to be answered in these cases are: how many software bugs remain in the software and should one decide to stop testing the software?

It is known that quantitative measures for the reliability of software systems can be derived from software reliability models. And, as such, support the product development process. Over the past four decades, research activities in this area have been performed. As a result, many software reliability models have been proposed. It was shown that, once these models reach a certain level of convergence, it can enable the developer to release the software. And stop software testing accordingly. Criteria to determine the optimal testing time include the number of remaining errors, failure rate, reliability requirements, or total system cost. In this paper we will present our results in predicting the reliability of software for agile testing environments. We seek to model this way of working by extending the Jelinski-Moranda model to a 'stack' of feature-specific models, assuming that the bugs are labelled with the feature they belong to. In order to demonstrate the extended model, several prediction results of actual cases will be presented. The questions to be answered in these cases are: how many software bugs remain in the software and should one decide to stop testing the software?

We have seen an increasing number of reported colour maintenance issues in the market when it concerns LED-based products. Besides this, there are also requests to provide products that have < 2 SDCM colour point changes over lifetime. To understand the mechanisms behind colour maintenance in our LED-portfolio we have developed a calculation method that is able to predict colour maintenance as function of time, construction and material used. The details of that method are described in this paper.