Abstract. A challenging software engineering problem is the design and implementation of component-based (CB) applications that can meet specified performance requirements. Our PPCB approach has been developed to facilitate performance prediction of CB applications built using black-box component infrastructures such as J2EE. Such deployment scenarios are problematic for traditional performance modeling approaches, which typically focus on modeling application component performance and neglect the complex influence of the specific component technology that hosts the application. In this paper, an overview of the PPCB modeling approach is given. Example results from predicting the performance of a J2EE application are presented. These results are then statistically analyzed to quantify the uncertainty in the predicted results. The contribution of the paper is the presentation of concrete measures of the confidence an architect can have in the performance predictions produced by the PPCB...