The SHeffield ELicitation Framework (SHELF) is a package of documents,
templates and software to carry out elicitation of probability
distributions for uncertain quantities from a group of experts.
Elicitation is increasingly important for quantifying expert knowledge in
situations where hard data are sparse. This is often the context in which
difficult policy decisions are made. It is generally important to elicit
from a group of experts, rather than a single expert, in order to synthesise
the range of knowledge and opinions of the expert community. (However, SHELF
may be used for a single expert with only trivial modification.)
Despite this growing role for elicitation, there is little in the way of training
and support available to those who wish to conduct elicitations. SHELF is a
response to this shortage. By reading and carefully following the SHELF documentation,
it is possible for an untrained facilitator to carry out competent elicitation.
In September 2018, we will be running a four days of SHELF training,
with particular emphasis on practical issues of planning and conducting a SHELF elicitation workshop.
The third day (repeated on the fourth day) features hands-on training in facilitating and recording the elicitation.
Early registration is advised, particularly if you wish to attend the intensive,
hands-on session for facilitators on the third/fourth day.
This is a repeat of the successful training event in January.
Tony O'Hagan has designed an e-learning course
to teach people how to make the kind of probabilistic judgements that we ask of experts
in a SHELF elicitation workshop. The intention is that experts will prepare themselves
by taking this course, so making better use of the experts' time in the workshop itself.
Who are we?
SHELF has been developed by Tony O'Hagan and Jeremy Oakley, originally in the Department of
Probability and Statistics in the University of Sheffield. It arose out of our
long-standing commitment to research and practice in elicitation. The principal spur
for developing SHELF was discussions in the project "Bayesian Analysis in Microbial
Risk Assessment," led by Helen Clough at the University of Liverpool and Marc Kennedy
at the DEFRA Central Science Laboratory (CSL), and in particular the encouragement
of Andy Hart at CSL.
Click here to download the current version (3.0).
All materials in the SHELF package are made freely available, but they are
nevertheless covered by copyright. They may be copied for the purposes of
conducting elicitations, for private study or personal use.
They may not be reproduced on any website, offered for sale or otherwise
distributed without the written permission of either Tony O’Hagan or Jeremy Oakley.
Further information about using SHELF and using the SHELF name are given in the
"SHELF Overview.pdf" document in the SHELF package.
Version 1.0 of SHELF was released in 2008, and a minor upgrade, version 1.01,
implemented some small improvements to the R software.
Version 2.0 was released in September 2010 and was a significant upgrade.
New procedures and new templates were provided, there was
additional advice for facilitators and the software was completely revised.
Version 3.0 was released in October 2016 and is an even more substantial upgrade.
Enhancements include new procedures for multivariate elicitation,
extended advice documents and PowerPoint slide sets to help guide experts in making their judgements.
Version 3.1 will be released later in 2018. It will include new advice on eliciting knowledge about
many uncertain quantities. Users of SHELF who have joined our
mailing list are being invited to suggest further
Comments are welcomed by Tony O’Hagan
We would particularly welcome offers of additional materials or
suggested amendments to components of SHELF. We intend SHELF to be a growing
and open resource for anyone wishing to conduct effective elicitation.
Last updated: 24 March 2018
Maintained by: Tony O'Hagan