PDF reweighting in the Hessian matrix approach

We introduce the Hessian reweighting of parton distribution functions (PDFs). Similarly to the better-known Bayesian methods, its purpose is to address the compatibility of new data and the quantitative modifications they induce within an existing set of PDFs. By construction, the method discussed here applies to the PDF fits that carried out a Hessian error analysis using a non-zero tolerance $\Delta\chi^2$. The principle is validated by considering a simple, transparent example. We are also able to establish an agreement with the Bayesian technique provided that the tolerance criterion is appropriately accounted for and that a purely exponential Bayesian likelihood is assumed. As a practical example, we discuss the inclusive jet production at the LHC.Comment: The final version, to appear in JHE

The vision of zero risk tolerance in craft workers and operatives: an unattainable goal?

Taking health and safety risks is no longer tolerated on construction sites. Behavioural based safety model programmes often seek to change risk-taking behaviours and eliminate accidents. Risk is a cultural construct. Site work can be seen as inherently risky. Construction operatives take many risks that nonconstruction workers would not want to take; for example working on high scaffolds or roofs, climbing tower cranes, working below ground. This is in part why some people work in construction; they like taking those risks. Safety programmes impose a risk limit of zero on people. This would seem to be in conflict with an argument that some workers need to have, by the very nature of their work, a higher risk tolerance than most. Programmes often fail to manage personal risk-taking and therefore accidents still occur. A literature review was undertaken, drawing from authoritative sources in construction and psychology. Six qualitative interviews were undertaken with craft workers / operatives who had either been disciplined for risktaking on sites or who admitted to taking risks in their work. Condensed into vignettes, a narrative describes the actions and feelings of these workers. A high tolerance for risk was found, and given the nature of the work, this may indeed be necessary. There was no desire for reckless behaviour. The traditional industry drivers of production and speed are thought to be influential. High risk tolerance amongst workers may indicate that a vision of zero accidents may be unrealistic. To reduce levels of risk tolerance may be very difficult. More work is required to investigate how behavioural based programmes can be modified to take account of this aspect of construction site culture

Benchmarking occupational health and safety performance of Australian construction companies.

It is mandatory for Australian construction companies to provide a safe working environment for their workers and sub-contractors. Consequently, occupational health and safety (OHS) is a major issue for construction firms mainly due to the fear of prosecution. The recent introduction of Zero Tolerance by the Victorian government WorkCover Authority provided even higher OHS safety standards for the construction industry. This has placed a increased burden on construction companies especially small firms that are not in a position of financial strength.The size of the companies has been found to be a major contributing factor to the OHS performance of construction contractors. This research is based on benchmarking study of 44 construction companies in Victoria, Australia. The results show that the major factors influencing safety performance were; company size, and management commitment to OHS.<br /

Forward Performance Measurement with Applications in Indifference Valuation

In this thesis, we present basic ideas and key results for forward performance measurement. Besides, we provide an explicit construction of the optimal processes of a class of time-monotone forward performance processes. Moreover, starting with a two parameter family risk tolerance function, we construct a class of forward performance processes. By letting the parameter go to zero, we obtain the forward exponential utility. Finally, using the forward exponential utility, we solve the integrated portfolio management problem by the so-called utility-based approach and compare it with its classical backward indifference counterpart

Measuring the occupational health and safety performance of construction companies in Australia

Many facility managers are now required to deal directly with small firms engaged in the maintenance, alteration and cleaning of physical infrastructure. Increasingly the performance of small firms reflects on the manager of the facility, and so an understanding of their operation is required. It is mandatory for all firms to provide a safe working environment for their workers and subcontractors. Consequently, occupational health and safety (OHS) is a major issue for companies mainly due to the fear of prosecution. The introduction of Zero Tolerance by the Victorian government WorkCover Authority in 1999 provided even higher OHS safety standards for the construction industry. This has placed an increased burden on construction and maintenance companies especially small firms that are not in a position of financial strength. The size of the company has been found to be a major contributing factor to the OHS performance of construction contractors. This research is based on a benchmarking study of 44 construction companies in Victoria, Australia. The results show that the major factors influencing safety performance were; company size, and management and employee commitment to OHS.<br /