GLUE (uncertainty assessment)
Encyclopedia
In hydrology
, Generalized Likelihood
Uncertainty
Estimation
(GLUE) is a statistical method for quantifying the uncertainty of model predictions. The method has been introduced by Beven and Binley (1992). The basic idea of GLUE is that given our inability to represent exactly in a mathematical model
how nature works, there will always be several different models that mimic equally well an observed natural process (such as river discharge
). Such equally acceptable or behavioral models are therefore called equifinal
.
The methodology deals with models whose results are expressed as probability distribution
s of possible outcomes, often in the form of Monte Carlo simulations, and the problem can be viewed as assessing, and comparing between models, how good these representations of uncetainty are. There is an implicit understanding that the models being used are approximations to what might be obtained from a thorough Bayesian analysis of the problem if a fully adequate model of real-world hydrological processes were available.
Hydrology
Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...
, Generalized Likelihood
Likelihood
Likelihood is a measure of how likely an event is, and can be expressed in terms of, for example, probability or odds in favor.-Likelihood function:...
Uncertainty
Uncertainty
Uncertainty is a term used in subtly different ways in a number of fields, including physics, philosophy, statistics, economics, finance, insurance, psychology, sociology, engineering, and information science...
Estimation
Estimation
Estimation is the calculated approximation of a result which is usable even if input data may be incomplete or uncertain.In statistics,*estimation theory and estimator, for topics involving inferences about probability distributions...
(GLUE) is a statistical method for quantifying the uncertainty of model predictions. The method has been introduced by Beven and Binley (1992). The basic idea of GLUE is that given our inability to represent exactly in a mathematical model
Mathematical model
A mathematical model is a description of a system using mathematical concepts and language. The process of developing a mathematical model is termed mathematical modeling. Mathematical models are used not only in the natural sciences and engineering disciplines A mathematical model is a...
how nature works, there will always be several different models that mimic equally well an observed natural process (such as river discharge
Discharge (hydrology)
In hydrology, discharge is the volume rate of water flow, including any suspended solids , dissolved chemical species and/or biologic material , which is transported through a given cross-sectional area...
). Such equally acceptable or behavioral models are therefore called equifinal
Equifinality
Equifinality is the principle that in open systems a given end state can be reached by many potential means. The term is due to Ludwig von Bertalanffy, the founder of General Systems Theory. He prefers this term, in contrast to "goal", in describing complex systems' similar or convergent behavior...
.
The methodology deals with models whose results are expressed as probability distribution
Probability distribution
In probability theory, a probability mass, probability density, or probability distribution is a function that describes the probability of a random variable taking certain values....
s of possible outcomes, often in the form of Monte Carlo simulations, and the problem can be viewed as assessing, and comparing between models, how good these representations of uncetainty are. There is an implicit understanding that the models being used are approximations to what might be obtained from a thorough Bayesian analysis of the problem if a fully adequate model of real-world hydrological processes were available.
External links
- www.glue-uncertainty.org Lancaster University site with list of GLUE papers.