2:30  Philip Dawid (University of Cambridge)

Local Proper Scoring Rules

A scoring rule S(x, Q) measures the quality of a quoted distribution Q for an uncertain quantity X in the light of the realised value x of X.  It is proper when it encourages honesty, i.e, when, if your uncertainty about X is represented by a distribution P, the choice Q = P minimises your expected loss. Traditionally, a scoring rule has been called local if it depends on Q only through q(x), the density of Q at x.  The only proper local scoring rule is then the log-score, -log q(x).  For the continuous case, we can weaken the definition of locality to allow dependence on a finite number m of derivatives of q at x.  A characterisation is given of such order-m local proper scoring rules, and their behaviour under transformations of the outcome space. In particular, any m-local scoring rule with m > 0 can be computed without knowledge of the normalising constant of the density. Parallel results for discrete spaces will be given.

3:30 - 4:00 Tea break

4:00  Christl Donnelly (Imperial College London)

Badger culling to control bovine TB: its potential role in a science-led policy

In 1997 the so-called Krebs Report recommended a randomized field trial be undertaken to evaluate the effectiveness of badger culling as a method of reducing bovine TB incidence in cattle herds.  The Randomised Badger Culling Trial was carried out in 30 100-sq-km areas. Along with related studies, it provided insights into several epidemiological aspects of the multi-species disease system.  The coalition government is currently seeking views on its proposal to include badger culling as a component of a science-led policy to control bovine TB.  

5:00 Reception to be held in Foyer A, Ruth Deech Building