In February 2014, Singapore embarked on a 2-year trial of a Bus Service Reliability Framework (BSRF) to improve en-route bus regularity and reduce instances of bus bunching and prolonged waiting times. Based on London's Quality Incentive Contract, the Singapore model also imposes penalties or provides incentives to operators for increases/reductions of Excess Wait Time (EWT) beyond a certain route-specific baseline.Drawing on insights derived from research on performance-based contracts, this paper describes some key considerations surrounding this particular innovation in Singapore's overall bus regulatory framework. We also discuss an important advancement in our understanding of how bus users value reliability improvements through estimates obtained from stated preference data. At the same time, early indications from the trial have been encouraging.

Fault tree analysis (FTA) is a technique widely used in the study of the reliability of industrial systems and to quantify risks associated with potentially hazardous systems. Most of the studies carried out are related to how to construct a fault tree and how to carry out qualitative and quantitative analysis. However, this paper studies an approach for prioritisation and optimum resource allocation by making use of the FTA technique. The basic idea is to develop a simple procedure for the ranking of basic elements in the complex system, so that maximum increase in reliability can be achieved. We compare our approach with the existing basic event importance measures, and show that the simple approach is easy to apply and provides ranking that is similar to other more complicated approaches. In addition, the new ranking approach can be used at the initial stages of fault tree construction as it does not require the whole fault tree to be completely developed.

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