Action planning and control under uncertainty emerge through a desirability-driven competition between parallel encoding motor plans

Living in an uncertain world, nearly all of our decisions are made with some degree of uncertainty about the consequences of actions selected. Although a significant progress has been made in understanding how the sensorimotor system incorporates uncertainty into the decision-making process, the preponderance of studies focus on tasks in which selection and action are two separate processes. First people select among alternative options and then initiate an action to implement the choice. However, we often make decisions during ongoing actions in which the value and availability of the alternatives can change with time and previous actions. The current study aims to decipher how the brain deals with uncertainty in decisions that evolve while acting. To address this question, we trained individuals to perform rapid reaching movements towards two potential targets, where the true target location was revealed only after the movement initiation. We found that reaction time and initial approach direction are correlated, where initial movements towards intermediate locations have longer reaction times than movements that aim directly to the target locations. Interestingly, the association between reaction time and approach direction was independent of the target probability. By modeling the task within a recently proposed neurodynamical framework, we showed that action planning and control under uncertainty emerge through a desirability-driven competition between motor plans that are encoded in parallel.     

Integrating multiple wilderness values into a decision-making model for Denali National Park and Preserve

Decisions about how to manage wilderness recreation in Denali National Park and Preserve require managers to integrate a diverse set of public values, a process that typically involves balancing tradeoffs among multiple and often competing values. While decisions about how to manage wilderness are often contentious, previous research suggests that if managers are able to predict public support for various management alternatives the decisions become more tractable. This study develops a decision-making model that integrates social, resource, and managerial values associated with the Denali wilderness experience. Specifically, stated choice analysis is used to evaluate the choices overnight wilderness visitors make when faced with hypothetical tradeoffs among the conditions of social, resource, and management attributes of the Denali wilderness. Study findings offer an empirical approach for predicting and evaluating the likelihood of public support for Denali wilderness management alternatives.     

The ecology of rivers with contrasting flow regimes: identifying indicators for setting environmental flows

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Contrasting energy pathways at the community level as a consequence of regime shifts

Ecological regime shifts typically result in abrupt changes in ecosystem structure through several trophic levels, which leads to rapid ecosystem reconfiguration between regimes. An interesting aspect of the impact of regime shift is that alternative regimes may induce distinct shifts in energy pathways; these have been less tested than structural changes. This paper addresses this by using stable isotopes to establish the energy pathways in fish communities. We specifically focus on the impact of regime shift on changes of the energy pathways, and how the magnitude and direction of these changes affect the local community. We found that energy pathways significantly varied among the planktivorous, benthivorous, and piscivorous trophic guilds as a result of the alternative regimes. The regime shift from a clear to a turbid state altered the food web towards planktonic energy pathways and truncated food chain length, which is indicative of less ecological efficiency. This was confirmed by the adaptive foraging strategies of prevalent omnivores in the current communities. These structural and functional characteristics of trophic interactions might not facilitate classic trophic cascading effects in such a turbid regime and suppress the system’s response to environmental changes, e.g., nutrient loading, and restoration efforts in turbid to clear water regime shifts.     

Marine and freshwater regime changes impact a community of migratory Pacific salmonids in decline

Marine and freshwater ecosystems are increasingly at risk of large and cascading changes from multiple human activities (termed “regime shifts”), which can impact population productivity, resilience, and ecosystem structure. Pacific salmon exhibit persistent and large fluctuations in their population dynamics driven by combinations of intrinsic (e.g., density dependence) and extrinsic factors (e.g., ecosystem changes, species interactions). In recent years, many Pacific salmon have declined due to regime shifts but clear understanding of the processes driving these changes remains elusive. Here, we unpacked the role of density dependence, ecosystem trends, and stochasticity on productivity regimes for a community of five anadromous Pacific salmonids (Steelhead, Coho Salmon, Pink Salmon, Dolly Varden, and Coastal Cutthroat Trout) across a rich 40-year time-series. We used a Bayesian multivariate state-space model to examine whether productivity shifts had similarly occurred across the community and explored marine or freshwater changes associated with those shifts. Overall, we identified three productivity regimes: an early regime (1976–1990), a compensatory regime (1991–2009), and a declining regime (since 2010) where large declines were observed for Steelhead, Dolly Varden, and Cutthroat Trout, intermediate declines in Coho and no change in Pink Salmon. These regime changes were associated with multiple cumulative effects across the salmon life cycle. For example, increased seal densities and ocean competition were associated with lower adult marine survival in Steelhead. Watershed logging also intensified over the past 40 years and was associated with (all else equal) ≥97% declines in freshwater productivity for Steelhead, Cutthroat, and Coho. For Steelhead, marine and freshwater dynamics played approximately equal roles in explaining trends in total productivity. Collectively, these changing environments limited juvenile production and lowered future adult returns. These results reveal how changes in freshwater and marine environments can jointly shape population dynamics among ecological communities, like Pacific salmon, with cascading consequences to their resilience.     

Analysis of stability of different regimes of heart rate dynamics by computer modeling

Computer modeling revealed the following three regimes of heart rate dynamics: linear dynamics, “1st degree chaos,” and “2nd degree chaos.” This study investigated a stability of these regimes with respect to changes in initial conditions. The results show that the greatest stability is notable for the linear regime. For this regime small errors in values of initial conditions can not sharply change the initial dynamics of RR intervals. Both nonlinear regimes of heart rate dynamics are unstable, and a degree of instability of regime “2nd degree chaos” is higher in comparison with regime “1st degree chaos.” The results of computer modeling are in agreement with experimental data pointing to the existence of a relationship between the degree of heart rate irregularity and cardiac electrical stability.     

Uncertainty Analysis and Toxicity Classification in Life-Cycle Assessment Using the Case-study of Gas Purification Systems

This comprehensive thesis structures the decision-making process for making a choice of the most adequate gas purification system (GasPS). Various gas purification technologies (biofilter, activated carbon filter, catalytic oxidation, thermo-reactor) have been evaluated based on an industrial case-study for waste gas streams. The ecological performance was quantified using the life-cycle impact assessment methods Eco-Indicator 95 and Swiss Ecopoints (environmental scarcities). Both life-cycle impact assessment methods have been improved by a new classification method for volatile organic compounds (VOCs) which considers the environmental fate and exposure as well as the toxicity of these compounds. For life-cycle assessment, a detailed quantitative uncertainty analysis was carried out using Monte Carlo simulation. Based on the uncertainty analysis, developing statements about the significance of the results and of relative differences between various GasPS alternatives has been possible. The eco-efficiency of the investigated GasPSs was finally characterised based on four indicators: Net Ecological Benefit (NEB_N), Ecological Yield Efficiency (lgEYE), Net Present Value (NPV), and Ecological-Economic Efficiency (EEE).     

Data Quality

A methodology is presented to develop and analyze vectors of data quality attribute scores. Each data quality vector component represents the quality of the data element for a specific attribute (e.g., age of data). Several methods for aggregating the components of data quality vectors to derive one data quality indicator (DQI) that represents the total quality associated with the input data element are presented with illustrative examples. The methods are compared and it is proven that the measure of central tendency, or arithmetic average, of the data quality vector components as a percentage of the total quality range attainable is an equivalent measure for the aggregate DQI. In addition, the methodology is applied and compared to realworld LCA data pedigree matrices. Finally, a method for aggregating weighted data quality vector attributes is developed and an illustrative example is presented. This methodology provides LCA practitioners with an approach to increase the precision of input data uncertainty assessments by selecting any number of data quality attributes with which to score the LCA inventory model input data. The resultant vector of data quality attributes can then be analyzed to develop one aggregate DQI for each input data element for use in stochastic LCA modeling.     

Adaptive management of an environmental watering event to enhance native fish spawning and recruitment

1. A common goal of many environmental flow regimes is to maintain and/or enhance the river's native fish community by increasing the occurrence of successful spawning and recruitment events. However, our understanding of the flow requirements of the early life history of fish is often limited, and hence predicting their response to specific managed flow events is difficult. To overcome this uncertainty requires the use of adaptive management principles in the design, implementation, monitoring and adjustment of environmental flow regimes.
2. The Barmah-Millewa Forest, a large river red gum forest on the Murray River floodplain, south-east Australia, contains a wide variety of ephemeral and permanent aquatic habitats suitable for fish. Flow regulation of the Murray River has significantly altered the natural flood regime of the Forest. In an attempt to alleviate some of the effects of river regulation, the Forest's water regime is highly managed using a variety of flow control structures and also receives targeted Environmental Water Allocations (EWA). In 2005, the largest environmental flow allocated to date in Australia was delivered at the Forest.
3. This study describes the adaptive management approach employed during the delivery of the 2005 EWA, which successfully achieved multiple ecological goals including enhanced native fish spawning and recruitment. Intensive monitoring of fish spawning and recruitment provided invaluable real-time and ongoing management input for optimising the delivery of environmental water to maximise ecological benefits at Barmah-Millewa Forest and other similar wetlands in the Murray-Darling Basin.
4. We discuss possible scenarios for the future application of environmental water and the need for environmental flow events and regimes to be conducted as rigorous, large-scale experiments within an adaptive management framework.     

Mate choice and uncertainty in the decision process

The behavior of females in search of a mate determines the likelihood that a high quality male is encountered in the search process and alternative search strategies provide different fitness returns to searchers. Models of search behavior are typically formulated on an assumption that the quality of prospective mates is revealed to searchers without error, either directly or by inspection of a perfectly informative phenotypic character. But recent theoretical developments suggest that the relative performance of a search strategy may be sensitive to any uncertainty associated with the to-be-realized fitness benefit of mate choice decisions. Indeed, uncertainty in the decision process is inevitable whenever unobserved male attributes influence the fitness of searchers. In this paper, we derive solutions to the sequential search strategy and the fixed sample search strategy for the general situation in which observed and unobserved male attributes affect the fitness consequences of female mate choice decisions and we determine how the magnitude of various parameters that are influential in the standard models alter these more general solutions. The distribution of unobserved attributes amongst prospective mates determines the uncertainty of mate choice decisions-the reliability of an observed male character as a predictor of male quality-and the realized functional relationship between an observed male character and the fitness return to searchers. The uncertainty of mate choice decisions induced by unobserved male attributes has no influence on the generalized model solutions. Thus, the results of earlier studies of these search models that rely on the use of a perfectly informative male character apply even if an observed male trait does not reveal the quality of prospective mates with certainty. But the solutions are sensitive to any changes of the distribution of unobserved male attributes that alter the realized functional relationship between an observed character and the fitness return to searchers. For example, the standard sequential search model exhibits a reservation property--the acceptability of prospective mates is delimited by a unique threshold criterion--and the existence of this model property under generalized conditions depends critically on the association between the observed and unobserved male characters. In our formulations of the models we assumed that females use a single male character to evaluate the quality of prospective mates, but the model properties generalize to situations in which male quality is evaluated by a direct inspection of multiple male characters.     

Visual extrapolation under risk: human observers estimate and compensate for exogenous uncertainty

Humans commonly face choices between multiple options with uncertain outcomes. Such situations occur in many contexts, from purely financial decisions (which shares should I buy?) to perceptuo-motor decisions between different actions (where should I aim my shot at goal?). Regardless of context, successful decision-making requires that the uncertainty at the heart of the decision-making problem is taken into account. Here, we ask whether humans can recover an estimate of exogenous uncertainty and then use it to make good decisions. Observers viewed a small dot that moved erratically until it disappeared behind an occluder. We varied the size of the occluder and the unpredictability of the dot''s path. The observer attempted to capture the dot as it emerged from behind the occluded region by setting the location and extent of a ‘catcher’ along the edge of the occluder. The reward for successfully catching the dot was reduced as the size of the catcher increased. We compared human performance with that of an agent maximizing expected gain and found that observers consistently selected catcher size close to this theoretical solution. These results suggest that humans are finely tuned to exogenous uncertainty information and can exploit it to guide action.     

Paradox, Performance, and the Architecture of Decision-Making in Animals

The analysis of risk-sensitive foraging is beginning to explorethe psychological and cognitive mechanisms involved in decision-makingunder uncertainty as well as the more traditional functionalanalysis. Over the past 40 years cognitive psychologists exploringhuman decision-making have made great use of apparent "paradoxes"in rational choice behavior in elucidating aspects of information-processing.In this paper I review several of these paradoxes as they mightrelate to animal decisionmaking and the interpretation of cognitivearchitecture. The St. Petersburg Paradox can be related directlyto the original analysis of risk-sensitive foraging by focusingon the non-linear translation of resources into currencies ofevolutionary value, e.g., rate of energy gain. The Allais Paradoxfocuses on the need to evaluate the organism's perception ofprobabilities and possible non-linearities in the assignmentof likelihood. Various context- effects illustrate the potentialdifficulties associated with decision making over options withmultiple attributes. Where possible I illustrate the biologicalevaluation of the paradoxes discussed.     

A multiple-choice task with changes of mind

The role of changes of mind and multiple choices has recently received increased attention in the study of perceptual decision-making. Previously, these extensions to standard two-alternative tasks have been studied separately. Here we explored how changes of mind depend on the number of choice-alternatives. To this end, we tested 14 human subjects on a 2- and 4-alternative direction-discrimination task. Changes of mind in the participants' movement trajectories could be observed for two and for four choice alternatives. With fewer alternatives, participants responded faster and more accurately. The frequency of changes of mind, however, did not significantly differ for the different numbers of choice alternatives. Nevertheless, mind-changing improved the participants' final performance, particularly for intermediate difficulty levels, in both experimental conditions. Moreover, the mean reaction times of individual participants were negatively correlated with their overall tendency to make changes of mind. We further reproduced these findings with a multi-alternative attractor model for decision-making, while a simple race model could not account for the experimental data. Our experiment, combined with the theoretical models allowed us to shed light on: (1) the differences in choice behavior between two and four alternatives, (2) the differences between the data of our human subjects and previous monkey data, (3) individual differences between participants, and (4) the inhibitory interaction between neural representations of choice alternatives.     

Influence of Soil and Air Temperature on I. Nucleotide Metabolism and Growth of Phaseolus vulgaris L. seedlings

Eight day old greenhouse grown Phaseolus vulgaris L. seedlingswere exposed to three different temperature regimes. The concentrationof the total free nucleotides, nucleoside triphosphates, RNAand protein was much more pronounced in seedlings exposed tothe interactive day/night temperature of 28 ?C (soil) and 15?C (air) of regime I. Seedlings treated to a low soil/air, day/nighttemperature of 15 ?C (regime II) had the lowest content of totalfree nucleotides, nucleoside triphosphates, RNA and protein.The nucleoside triphosphate content and energy charge valueof seedlings treated to a high soil/air, day/night temperatureof 28 ?C (regime III) declined much earlier than in the seedlingsexposed to temperature regimes I and II. The fresh and dry weightof seedlings exposed to temperature regime I was significantlyhigher than those seedlings exposed to the other two temperatureregimes. The slowest growth was observed in seedlings exposedto temperature regime II. The noticeably higher concentrationof ATP, pyridine nucleotides and root nodulation in seedlingsexposed to temperature regime I suggests that higher soil andlow air temperature enhances nitrogen metabolism in P. vulgarisseedlings.     

Incorporating costs in LCA

The goal of LCA is to identify the environmental impacts resulting from a product, process, or activity. While LCA is useful for evaluating environmental attributes, it stops short of providing information that business managers routinely utilize for decision-making — i.e., dollars. Thus, decisions regarding the processes used for manufacturing products and the materials comprising those products can be enhanced by weaving cost and environmental information into the decision-making process. Various approaches have been used during the past decade to supplement environmental information with cost information. One of these tools is environmental accounting, the identification, analysis, reporting, and use of environmental information, including environmental cost data. Environmental cost accounting provides information necessary for identifying the true costs of products and processes and for evaluating opportunities to minimize those costs. As demonstrated through two case studies, many companies are incorporating environmental cost information into their accounting systems to prioritize investments in new technologies and products.     

Multi-attribute mate choice decisions and uncertainty in the decision process: a generalized sequential search strategy

The behavior of females in search of a mate determines the likelihood that high quality males are encountered and adaptive search strategies rely on the effective use of available information on the quality of prospective mates. The sequential search strategy was formulated, like most models of search behavior, on the assumption that females obtain perfect information on the quality of encountered males. In this paper, we modify the strategy to allow for uncertainty of male quality and we determine how the magnitude of this uncertainty and the ability of females to inspect multiple male attributes to reduce uncertainty influence mate choice decisions. In general, searchers are sensitive to search costs and higher costs lower acceptance criteria under all versions of the model. The choosiness of searchers increases with the variability of the quality of prospective mates under conditions of the original model, but under conditions of uncertainty the choosiness of searchers may increase or decrease with the variability of inspected male attributes. The behavioral response depends on the functional relationship between observed male attributes and the fitness return to searchers and on costs associated with the search process. Higher uncertainty often induces searchers to pay more for information and under conditions of uncertainty the fitness return to searchers is never higher than under conditions of the original model. Further studies of the performance of alternative search strategies under conditions of uncertainty may consequently be necessary to identify search strategies likely to be used under natural conditions.     

Observer variation in field assessments of vegetation condition: Implications for biodiversity conservation

Summary   Uncertainty in assessments of vegetation condition that are used to inform land management and planning decisions for biodiversity conservation in Australia may lead to unexpected outcomes, including loss of biodiversity. This study investigates observer error in field estimates of vegetation attributes, one component of uncertainty in assessments of vegetation condition. Ten observers conducted vegetation condition assessments using two assessment protocols (BioMetric and Habitat Hectares) on 20 sites in a grassy woodland community. Observers' estimates varied substantially across multiple scoring categories for all vegetation attributes on almost all sites. Across all sites, the average coefficient of variation in total vegetation condition scores was 15–18% for both protocols, with a maximum of 60%. The primary cause of variation in total vegetation condition scores was random error in raw estimates of vegetation attributes, although sensitivity of some highly weighted attributes to error exacerbated variation in some cases. Observers generally agreed on the total scores and ranks of highly degraded (pasture) sites, but were less consistent on other sites. Rank correlations between pairs of observers were stronger for Habitat Hectares, suggesting BioMetric may be slightly more sensitive to observer error. It is recommended that: (i) research is undertaken into methods for reducing observer error; (ii) review is made of the sensitivity of index scoring structures to observer error; (iii) field observers estimate uncertainty around point estimates of vegetation condition; and, (iv) decision-makers explicitly incorporate uncertainty into the decision-making processes and aim for outcomes that are robust to this uncertainty.     

Thermodynamic view on decision-making process: emotions as a potential power vector of realization of the choice

This research is devoted to possible mechanisms of decision-making in frames of thermodynamic principles. It is also shown that the decision-making system in reply to emotion includes vector component which seems to be often a necessary condition to transfer system from one state to another. The phases of decision-making system can be described as supposed to be nonequilibrium and irreversible to which thermodynamics laws are applied. The mathematical model of a decision choice, proceeding from principles of the nonlinear dynamics considering instability of movement and bifurcation is offered. The thermodynamic component of decision-making process on the basis of vector transfer of energy induced by emotion at the given time is surveyed. It is proposed a three-modular model of decision making based on principles of thermodynamics. Here it is suggested that at entropy impact due to effect of emotion, on the closed system—the human brain,—initially arises chaos, then after fluctuations of possible alternatives which were going on—reactions of brain zones in reply to external influence, an order is forming and there is choice of alternatives, according to primary entrance conditions and a state of the closed system. Entropy calculation of a choice expectation of negative and positive emotion shows judgment possibility of existence of “the law of emotion conservation” in accordance with several experimental data.     

Protein adsorption at the oil/water interface: characterization of adsorption kinetics by dynamic interfacial tension measurements.

The dynamics of protein adsorption at an oil/water interface are examined over time scales ranging from seconds to several hours. The pendant drop technique is used to determine the dynamic interfacial tension of several proteins at the heptane/aqueous buffer interface. The kinetics of adsorption of these proteins are interpreted from tension/log time plots, which often display three distinct regimes. (I) Diffusion and protein interfacial affinity determine the duration of an initial induction period of minimal tension reduction. A comparison of surface pressure profiles at the oil/water and air/water interface reveals the role of interfacial conformational changes in the early stages of adsorption. (II) Continued rearrangement defines the second regime, where the resulting number of interfacial contacts per protein molecule causes a steep tension decline. (III) The final regime occurs upon monolayer coverage, and is attributed to continued relaxation of the adsorbed layer and possible build-up of multilayers. Denaturation of proteins by urea in the bulk phase is shown to affect early regimes.     

Approaches to Ecological Risk Characterization and Management: Selecting the Right Tools for the Job

Chemical-specific hazard quotient (HQ) risk characterization in ecological risk assessment (ERA) can be a value-added tool for risk management decision-making at chemical release sites, when applied appropriately. However, there is little consensus regarding how HQ results can be used for risk management decision-making at the population, community, and ecosystem levels. Furthermore, stakeholders are reluctant to consider alternatives to HQ results for risk management decisions. Chemical-specific HQs risk characterization should be viewed as only one of several approaches (i.e., tools) for addressing ecological issues; and in many situations, other quantitative and qualitative approaches will likely result in superior risk management decisions. The purpose of this paper is to address fundamental issues and limitations associated with chemical-specific HQ risk characterization in ERA, to identify when it may be appropriate, to explore alternatives that are currently available, and to identify areas that could be developed for the future. Several alternatives (i.e., compensatory restoration, performance-based ecological monitoring, ecological significance criteria, net environmental benefit analysis), including their limitations, that can supplement, augment, or substitute for HQs in ERA are presented. In addition, areas of research (i.e., wildlife habitat assessment/landscape ecology/population biology, and field validated risk-based screening levels) that could yield new tools are discussed.