Research
Funded projects
Publications
Technical reports
Statistics & probability
Other science
Economics & finance
Other
Statistics 2
SAPPUR
Miscellaneous
Presentations
Memberships, committees
Words that have yet to appear in on-line dictionaries
Contact:
Department of Mathematics
University of Bristol
University Walk
Bristol BS8 1TW
tel: +44 (0)117 9287782
fax: +44 (0)117 9287999
j.c.rougier@bristol.ac.uk
Find me:
Room 4.12, left out of the lift on the fourth floor of the main Maths building.
Treat me:
Japanese green tea and a slice of vegan fruitcake at Boston Tea Party on Park Street.
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Jonathan (Jonty) Rougier's homepage
Senior Lecturer in Statistics,
Department of
Mathematics, University of
Bristol, UK.
Research
My research concerns the probabilistic representation of uncertainty
in science, particularly in climate science. The main issues I think
about are:
- How do we use scientific models? If they are to be used
quantatively to predict the behaviour of a system, e.g. the
climate, how do we represent the discrepancy between the model and
the system?
- Is there a general framework for combining model-evaluations,
system observations, and expert judgements, that is applicable
across different areas of science?
- What is the role of probability in representing our
uncertainty? What does a probability represent, and what are the
limitations of the probability calculus? What is the best way to
explain probabilistic concepts to non-statisticians?
- How do we implement our inferential calculations with very
large models, that may take weeks or even months to evaluate?
What corners do we cut?
Funded projects
- SAPPUR: scoping
study on risk and uncertainty in natural hazards. This £130k
scoping study will take place over June to October 2009 and aims to
provide an overview of tools and methodologies for the analysis,
propagation and communication of uncertainty and risk within natural
hazards science. BRISK will be working with the rest of the UK
scientific community and international experts to provide the
background and recommendations to help NERC develop a world-class
research programme.
- MUCM.
"The MUCM project will develop a technology that is capable of
addressing all sources of uncertainty in model predictions and to
quantify their implications efficiently, even in the most complex
models. It has the potential to revolutionise scientific debate
by resolving the contradictions in competing models. It will also
have a radical effect on everyday modelling and model usage by
making the uncertainties in model outputs transparent to modellers
and end users alike." Funded by Research Councils UK.
- UK Met
Office. External expert to advise on
uncertainty, particularly with respect to the QUMP project and UKCIP08. Funded by
Defra.
QUMP stands for Quantifying Uncertainty in Model Predictions:
it is an experiment run by the scientists in the Met Office, to
look at the effect of perturbing the parameters of the HadCM3
climate model. A complementary project is run by climateprediction.net.
- PalaeoQUMP:
"PalaeoQUMP aims to constrain climate sensitivity [...]
using a wider range of derived climate observations from the
geological past (reconstructions from sediments and
geomorphological changes for the Last Glacial Maximum and the
mid-Holocene period), to evaluate climate model predictions
generated using the same series of simulations as QUMP produced
for the modern climate." Funded by NERC QUEST.
- THC
MIP. This is a project to compare the way in which different
ocean models represent the thermohaline circulation (THC). A
crucial question is the degree to which we can capture this very
complicated phenomenon with quite simple models. Funded by NERC RAPID.
- CASE studentship: Estimating and reducing the uncertainty in the future
behaviour of the Greenland ice sheet.
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Publications
Technical reports
In submission
- J.C. Rougier and M. Kern (2010), Predicting Snow Velocity in Large
Chute Flows Under Different Environmental Conditions.
Assimilating observations, model predictions, and expert judgements
into a prediction for snow behaviour. Joint work with Martin Kern at
the BFW Institute for Natural Hazards and Alpine Timberline. Revised
version, available as a pdf file
(revised 8 Feb, 2010).
- M. Goldstein, L. House, and J.C. Rougier (2008), Assessing model
discrepancy using a multi-model ensemble.
How to combine an ensemble of model-evaluations with observations,
where we have them, to assess the mean vector and variance matrix of
the discrepancy between our model and reality. Uses second-order
exchangeability as the statistical model for the ensemble, so does not
insist on model 'independence', but allows for shared biases in
models. Has an illustration using climate models from the IPCC AR4
multi-model ensemble. Available as a pdf file,
includes some colour plots (3.3MB). Slides
available (6MB).
Promised
These papers are almost finished ...
- J.C. Rougier, D. Cameron, N. Edwards (2008), Precalibrating an
intermediate complexity climate model.
A more robust (but less powerful) approach to ruling out regions of
model parameter-space, using the 'implausibility' approach.
Computationally intensive but inferentially (relatively) undemanding.
Other people
- I. Scheel, P. Green, and J.C. Rougier (2008), Identifying influential
model choices in Bayesian hierarchical models.
A graphical approach to identifying potential misspecification in
the tails of hierarchical models expressed as chain graphs. Available
as a pdf
file, with supplementary
information.
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Statistics and Probability
J.C. Rougier, S. Guillas, A. Maute, A.D. Richmond (2009), Expert
Knowledge and Multivariate Emulation: The Thermosphere-Ionosphere
Electrodynamics General Circulation Model
(TIE-GCM), Technometrics, 51(4), 414-424. doi:10.1198/TECH.2009.07123
M. Goldstein and J.C. Rougier (2009), Reified Bayesian Modelling
and Inference for Physical Systems, Journal of Statistical Planning
and Inference, 139(3), 1221-1239. doi:10.1016/j.jspi.2008.07.019
With discussion and rejoinder.
J.C. Rougier (2008), Efficient Emulators for Multivariate
Deterministic Functions, Journal of Computational and Graphical
Statistics, 17(4), 827-843. doi:10.1198/106186008X384032. R package OPE_0.8.tar.gz.
J.C. Rougier (2008), Discussion of 'Inferring Climate System
Properties Using a Computer Model', by Sanso et al, Bayesian
Analysis, 3(1), 45-56. DOI:10.1214/08-BA301B
M. Goldstein and J.C. Rougier (2006), Bayes
Linear Calibrated Prediction for Complex Systems, Journal of the
American Statistical Association, 101 (no. 475), 1132-1143.
M. Goldstein and J.C. Rougier (2004),
Probabilistic Formulations for Transferring Inferences from
Mathematical Models to Physical Systems, SIAM Journal on Scientific
Computing, 26(2), 467-487.
I. MacPhee, J.C. Rougier and G. Pollard (2004), Server Advantage
in Tennis Matches, Journal of Applied Probability,
41(4), 1182-1186.
J.C. Rougier and M. Goldstein (2001), A Bayesian Analysis of Fluid
Flow in Pipelines, Applied Statistics, 50(1), 77-93.
P.S. Craig, M. Goldstein, J.C. Rougier and A.H. Seheult (2001),
Bayesian Forecasting for Complex Systems Using Computer Simulators,
Journal of the American Statistical Association, 96,
717-729.
Other science
S. Guillas, J.C. Rougier, A. Maute, A.D. Richmond, and
C.D. Linkletter (2009), Bayesian calibration of the
Thermosphere-Ionosphere Electrodynamics General Circulation Model
(TIE-GCM), Geoscientific Model Development, 2,
137-144. Available
online.
M. Crucifix and J.C. Rougier (2009), On the use of simple dynamical systems
for climate predictions: A Bayesian prediction of the next glacial
inception. The European Physics Journal - Special Topics, 174(1),
11-31. DOI:10.1140/epjst/e2009-01087-5
J.C. Rougier, D.M.H. Sexton, J.M. Murphy, and D. Stainforth (2009),
Analysing the climate sensitivity of the HadSM3 climate model using
ensembles from different but related experiments. Journal of
Climate, 22(13), 3540-3557. DOI:10.1175/2008JCLI2533.1
J.C.Rougier and D.M.H. Sexton (2007),
Inference in Ensemble Experiments, Philosophical Transactions of
the Royal Society, Series A, 365, 2133-2143.
J.C. Rougier (2007), Probabilistic
Inference for Future Climate Using an Ensemble of Climate Model
Evaluations, Climatic Change, 81, 247-264. DOI:10.1007/s10584-006-9156-9
J.C Rougier (2005), Probabilistic Leak Detection in Pipelines
Using the Mass Imbalance Approach. Journal of Hydraulic
Research, 43(5), 556-566.
M. van Oijen, J.C. Rougier and R. Smith (2005), Bayesian
Calibration of Process-Based Forest Models: Bridging the Gap Between
Models and Data, Tree Physiology, 25, 915-927.
Economics and Finance
S.C. Parker and J.C. Rougier (2007), The Retirement Behaviour of
the Self-Employed in Britain, Applied Economics, 39(6), 697-713.
P.R. Holmes and J.C. Rougier (2005), Trading Volume and Contract
Rollover in Futures Contracts, Journal of Empirical Finance,
12(2), 317-338.
S.C. Parker and J.C. Rougier (2001), Measuring Social Mobility as
Unpredictability, Economica, 68, 63-76.
B. Hillier and J.C. Rougier (1999), Real Business Cycles,
Investment Finance and Multiple Equilibria, Journal of Economic
Theory, 86, 100-22.
J.C. Rougier (1997), A Simple Necessary Condition for Negativity
in the Almost Ideal Demand System with the Stone Price Index,
Applied Economics Letters, 4, 97-9.
J.C. Rougier (1996), An Optimal Price Index for Stock Index
Futures Contracts, Journal of Futures Markets, 16,
189-99.
J.C. Rougier (1993), The Impact of Margin-Traders
on the Distribution of Daily Stock Returns: The London Stock Exchange,
Applied Financial Economics, 3, 325-8.
Non-peer-reviewed
J.C. Rougier (2009), Notes on statistical modelling for complex
systems, ver. 0.5, unpublished. Available as a pdf file. Please note the version
number: this document is still evolving.
J.C. Rougier (2008), Climate change detection and attribution, ISBA
bulletin, 15(4), 3-6. Available on-line.
J.C. Rougier (2008), Formal Bayes Methods for Model Calibration
with Uncertainty, in K. Beven and J. Hall (eds), Applied Uncertainty
Analysis for Flood Risk Management, Imperial College Press / World
Scientific. Draft version available as a pdf
file.
J.C. Rougier (2006), Comment on the paper by Haslett et al.,
Journal of the Royal Statistical Society, Series A,
169(3), 432-433.
J.C. Rougier (2005), Literate Programming for Creating and
Maintaining Packages. R News, 5(1), 35-39.
J.C. Rougier (2004), Comment on the paper by Murphy et al. Nature did not
want to publish this comment, but I think it says some useful things.
Available as a pdf file.
J.C. Rougier (2001), Comment on the paper by Kennedy and
O'Hagan, Journal of the Royal Statistical Society, Series B,
63, page 453.
J.C. Rougier (2001), What's the Point of `tensor'?, R
News, 1(2), 26-27.
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Miscellaneous
Presentations
- Uncertainty and risk in natural hazards, Nottingham, Nov
2009. Slides available.
- Introduction to computer experiments, and the challenges of expensive
models, RSS Statistical Computing Section, Bath, October
2009. Slides available.
- Quantifying uncertainty in probability of exceedence (PE) curves,
NERC/KTN workshop on Catastrophe modelling for natural hazard impact, Lloyd's,
London, Oct 2009. Slides available and
also R code for the pictures.
- Emulator-based simulator calibration for high-dimensional data, JCGS session, JSM-2009, Washington DC, Aug 2009. Slides available.
- The What, Why, and How of Multivariate Emulation, Spring
Research Conference On Statistics in Industry and Technology,
Vancouver, May 2009. Slides available.
- Simple models for glacial cycles, Bath Institute for Complex
Systems, Feb 2009. Slides available.
- Statistical calibration of physical models, WSL Institute for
Snow and Avalanche Research SLF, Davos, Switzerland, Dec 2008. Slides available.
Memberships, Committees
- Fellow, Royal
Statistical Society, 1997 -, Environmental
Statistics Section, 2005 -
- International Society for
Bayesian Analysis (ISBA), 2001 -
- Associate Editor, Applied Statistics (Journal of the Royal Statistical
Society, Series C), 2009 -
- Reviewer, European Research Council, 2009 -
Words that have yet to appear in on-line dictionaries
Hie (vb; hies, hied, hieing or occas. hying). To go quickly or
hasten, to flee. Example (Fowler) "Hie to your chamber". Fowler says
archaic or poetical only, which is a bit too strong, I reckon.
Upversion (vb, with obj.). To take something, typically a
software program, to the next version. Example (from the web) "To get
our nightly builds running again, I need to upversion the plugins."
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