Time filter

Source Type

Oxford, United Kingdom

Cox D.R.,Nuffield College | Wong M.Y.,Hong Kong University of Science and Technology
Biometrika | Year: 2010

A simple case of Poisson regression is used to study the potential gain in efficiency from using a mixed model representation. Possible systematic errors arising from misspecification of the random terms in the model are examined. It is shown in particular that for a special but realistic problem, appreciable bias may arise from misspecification of a random component. © 2010 Biometrika Trust. Source

Cox D.R.,Nuffield College
Biometrika | Year: 2014

So-called big data are likely to have complex structure, in particular implying that estimates of precision obtained by applying standard statistical procedures are likely to be misleading, even if the point estimates of parameters themselves may be reasonably satisfactory. While this possibility is best explored in the context of each special case, here we outline a fairly general representation of the accretion of error in large systems and explore the possible implications for the estimation of regression coefficients. The discussion raises issues broadly parallel to the distinction between short-range and long-range dependence in time series theory. © 2015 Biometrika Trust. Source

Przepiorka W.,Nuffield College
Proceedings. Biological sciences / The Royal Society | Year: 2013

Social control and the enforcement of social norms glue a society together. It has been shown theoretically and empirically that informal punishment of wrongdoers fosters cooperation in human groups. Most of this research has focused on voluntary and uncoordinated punishment carried out by individual group members. However, as punishment is costly, it is an open question as to why humans engage in the punishment of wrongdoers even in one-time-only encounters. While evolved punitive preferences have been advocated as proximate explanations for such behaviour, the strategic nature of the punishment situation has remained underexplored. It has been suggested to conceive of the punishment situation as a volunteer's dilemma (VOD), where only one individual's action is necessary and sufficient to punish the wrongdoer. Here, we show experimentally that implementing the punishment situation as a VOD sustains cooperation in an environment where punishers and non-punishers coexist. Moreover, we show that punishment-cost heterogeneity allows individuals to tacitly agree on only the strongest group member carrying out the punishment, thereby increasing the effectiveness and efficiency of social norm enforcement. Our results corroborate that costly peer punishment can be explained without assuming punitive preferences and show that centralized sanctioning institutions can emerge from arbitrary individual differences. Source

van de Rakt M.,Radboud University Nijmegen | Ruiter S.,Netherlands Institute for the Study of Crime and Law Enforcement NSCR | de Graaf N.D.,Nuffield College | Nieuwbeerta P.,Leiden University
Journal of Quantitative Criminology | Year: 2010

Criminal behavior of parents substantially affects the criminal behavior of children. Little is known, however, about how crime is transmitted from one generation to the next. In order to test two possible explanations against each other, we pose the question whether the timing of the criminal acts of fathers is important for children's chances of committing crime. Static theories predict that it is the number of delinquent acts performed by fathers that is important, and that the particular timing does not affect the child's chance of committing crime. Dynamic theories state that the timing is important, and children have a greater chance of committing crime in the period after fathers have committed delinquent acts. Results show that the total number of convictions of a father is indeed very important, but also the exact timing is key to understanding intergenerational transmission of crime. In the year a father is convicted the chance his child is also convicted increases substantially and it decays in subsequent years. This decay takes longer the more crimes father has committed. Our results show that some of the assumptions of the static theories at least need to be adjusted. © 2010 The Author(s). Source

Gallagher J.,Nuffield College
British Journal of Politics and International Relations | Year: 2012

This article provides a commentary on the evolution of intergovernmental relations in the UK from one of its leading practitioners. As the former Director General for Devolution in the UK Cabinet Office and the UK Ministry of Justice, Jim Gallagher was at the centre of the process of intergovernmental exchange, and provides rich practice-based insights into both the character and dynamics of IGR before and after 2007. © 2012 The Authors. British Journal of Politics and International Relations © 2012 Political Studies Association. Source

Discover hidden collaborations