Decision trees are hierarchical, sequential classification structures that recursively partition the set of observations (data) and are used to represent rules underlying the observations. This article describes the development of TreeWorks, a tool that enhances existing decision tree theory and...

This paper describes the development and application of a simulation tool for modelling patient choice in healthcare systems. Patient choice is already offered in the English National Health Service (NHS) and proposed reforms will propel choice to the forefront of NHS re-structuring by offering...

Firms often delegate important decisions to committees which are set up specifically for that purpose; for example selection committees. We analyze the equilibrium behavior of a game in which committee members (the players) interview candidates sequentially, either hiring or going on to the next...

This paper studies the estimation of a semi-strong GARCH(1,1) model when it does not have a stationary solution, where semi-strong means that we do not require the errors to be independent over time. We establish necessary and sufficient conditions for a semi-strong GARCH(1,1) process to have a...

We propose estimators of previous termfeatures of the distributionnext term of an unobserved random variable W. What is observed is previous termanext term sample of Y,V,X where previous termanext term binary Y equals one when W exceeds previous termanext term threshold V determined by...

In times of ever increasing financial constraints on public weather services it is of growing importance to communicate the value of their forecasts and products. While many diagnostic tools exist to evaluate forecast systems, intuitive diagnostics for communicating the skill of probabilistic...

Empirical evidence has emerged of the possibility of fractional cointegration such that the gap, β, between the integration order δ of observable time series and the integration order γ of cointegrating errors is less than 0.5. This includes circumstances when observables are stationary or...

We develop a sequence of tests for specifying the cointegrating rank of, possibly fractional, multiple time series. Memory parameters of observables are treated as unknown, as are those of possible cointegrating errors. The individual test statistics have standard null asymptotics and are...

The recent surge in studies analysing spatial dependence in political science has gone hand-in-hand with increased attention paid to the choice of estimation technique. In comparison, specification choice has been relatively neglected, even though it leads to equally, if not more, serious...

Ensemble prediction systems aim to account for uncertainties of initial conditions and model error. Ensemble forecasting is sometimes viewed as a method of obtaining (objective) probabilistic forecasts. How is one to judge the quality of an ensemble at forecasting a system? The probability that...