Juggling Preferences in a World of Uncertainty

[Context/Motivation] Decision-making for self-adaptive systems (SAS) requires the runtime trade-off of multiple non-functional requirements (NFRs) and the costs-benefits analysis of the alternative solutions. Usually, it requires the specification of weights for NFRs and decision-making strategies. Generally, these weights are defined at design-time with the support of previous experiences and domain experts. [Questions/Problems] Under some specific conditions detected at runtime, it can be the case that the weights assigned to the NFR at design time may not be suitable anymore at runtime. As a result, the system may not behave in the expected way and it may either execute unnecessary adaptations or miss crucial adaptations with a detrimental effect on the behaviour of the system. [New ideas/early results] In this RE@Next! paper, we introduce a novel approach for automatic runtime reappraisal of the weights of NFRs given new evidence collected from the environment during the execution of the system. Our early results suggest, as expected, that the approach improves the decision-making process by allowing the reappraisal and update of the weights of the NFRs in accordance to the newly detected environmental context.