Computer codes are used in scientific research to study and predict the behaviour of complex systems. Their run times often make uncertainty sensitivity analyses impractical because thousands runs that conventionally required, so efficient techniques have been developed based on a statistical representation code. The approach is less straightforward for dynamic codes, which represent time-evolving We develop novel iterative system build model computer demonstrated rainfall-runoff simulator.

Abstract The microphysical properties of convective clouds determine their radiative effects on climate, the amount and intensity precipitation as well dynamical features. Realistic simulation these cloud presents a major challenge. In particular, because models are complex slow to run, we have little understanding how considerable uncertainties in parameterized processes feed through uncertainty responses. Here use statistical emulation enable Monte Carlo sampling model quantify sensitivity...

Knowledge about regional and local climate change can inform risk assessments adaptation decisions. However, estimates of future precipitation at the level are deeply uncertain for many parts world. A novel methodology was developed that uses processes expert elicitation to build narratives change. The qualitatively describe physically plausible evolutions substantiated by processes. This method is applied Indian Summer Monsoon, focusing on Cauvery River Basin in Karnataka, Southern India....

Summary A crucial issue in the current global warming debate is effect of vegetation and soils on carbon dioxide (CO2) concentrations atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay soil organic matter disturbance effects such as fire return it to The balance these processes net flux. To estimate biospheric flux for England Wales, we address statistical problem inference sum multiple outputs from a complex deterministic computer code whose input...

Carcinogenic potency is a key factor in the understanding of chemical risk assessment. Measures carcinogenic potency, for example TD

As the basis for managing risks of chemical exposure, Chemical Risk Assessment (CRA) process can impact a substantial part economy, health hundreds millions people, and condition environment. However, number properly assessed chemicals falls short societal needs due to lack experts evaluation, interference third party interests, sheer volume potentially relevant information on from disparate sources. In order explore ways in which computational methods may help overcome this discrepancy...

Sentence severity has increased in England and Wales recent years. The causes of the increase remain unclear. One possible explanation relates to introduction sentencing guidelines, which seem coincide time with sentence severity. To date, investigations this hypothesis have been limited simple exploratory analyses or specific offences. We use a new scale severity—developed using Thurstone scaling participation 21 magistrates—and time-series modelling explore whether causal effect can be...

Abstract Many methods for modeling functions over high-dimensional spaces assume global smoothness properties; such assumptions are often violated in practice. We introduce a method that display heterogeneity or contain discontinuities. The is dealt with by using combination of Voronoi tessellation, to partition the input space, and separate Gaussian processes model function different regions partitioned space. proposed highly flexible since it allows cells combine form regions, which...

Computer simulators of real-world processes are often computationally expensive and require many inputs. The problem the computational expense can be handled using emulation technology; however, highly multidimensional input spaces may more simulator runs to train validate emulator. We aim reduce dimensionality by screening simulator's inputs for nonlinear effects on output rather than distinguishing between negligible active effects. Our proposed method is built upon elementary (EE) uses a...

Tox21 and ToxCast are high-throughput in vitro screening programs coordinated by the U.S. National Toxicology Program Environmental Protection Agency, respectively, with goal of forecasting biological effects vivo based on bioactivity profiling. The present study investigated whether mechanistic insights targets food-relevant chemicals can be obtained from results when grouped according to structural similarity. Starting 556 direct additives that have been identified database Karmaus et al....

In the context of statistical analysis, elicitation is process translating someone's beliefs about some uncertain quantities into a probability distribution. The person's judgements are usually fitted to member convenient parametric family. This approach does not allow for possibility that any number distributions could fit same judgements. this paper, an expert's treated as other inference problem: facilitator exercise has prior form density function, elicits and facilitator's function...

Since the foot‐and‐mouth disease outbreak of 2001 in United Kingdom, there has been debate about sharing, between government and industry, both costs livestock outbreaks responsibility for decisions that give rise to them. As part a consultation into formation new body manage diseases, veterinarians economists produced estimates average annual number exotic infectious diseases. In this article, we demonstrate how experts were helped quantify their uncertainties cost using formal expert...

We introduce a strategy for quantifying and synthesising uncertainty about elements of risk assessment using Bayes linear methods. view the population subjective belief structures use adjustments as flexible transparent tool assessors who want to quantify their hazard based on disparate sources information. For motivation, we an application human skin sensitisation where there are many competing information available.

Abstract Pharmaceutical companies regularly need to make decisions about drug development programs based on the limited knowledge from early stage clinical trials. In this situation, eliciting judgements of experts is an attractive approach for synthesising evidence unknown quantities interest. When calculating probability success a program, multiple interest—such as effect different endpoints—should not be treated unrelated. We discuss two approaches establishing multivariate distribution...

Vegetable oils and fats make up a significant part of the energy intake in typical European diets. However, their use as ingredients diverse range different foods means that consumption is often hidden, especially when are used for cooking. As result, there no reliable estimates vegetable diet consumers in, example, nutritional assessments or chemical risk assessments. We have developed an innovative model to estimate by Union using databases elements probabilistic modelling. A key feature...