Correlated racing evidence accumulator models

A dramatic increase in talking on the phone whilst driving has been seen over the past decades, which posed a significant safety threat on the whole society consequently. Studies on the topic regarding the effect of phone conversations on drivers’ driving performances have never come to a cease, especially on the studies of drivers’ brake response times. However, few studies focus on the relationship between situation criticality and the effect of cognitive load on drivers’ brake responses. To better understand it, a driving simulator experiment with two braking scenarios corresponding to two levels of situation criticality was conducted in this study. Participants were asked to follow a lead vehicle as they normally did and answer arithmetic problems (simple and complex) in three phone modes (baseline, hands-free, and handheld) in the meantime. Drivers’ brake response times to the lead vehicle under five conditions were collected and fitted in accumulator models, in which visual looming and brake lights onset were included as the sensory cues. Results demonstrated that the previously proposed mechanistically explicit simulation model was able to predict drivers’ brake response times on different levels of cognitive load and the increased effect of cognitive load on drivers’ brake response times in less critical situations was demonstrated in this paper as well.

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Influence of Hydraulic Accumulator Performance on the Hydraulic Hybrid Powertrain

ASME/BATH 2019 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2019-1709 ◽

2019 ◽

Author(s):

Qi Zhang ◽

Feng Wang ◽

Bing Xu ◽

Kim A. Stelson

Keyword(s):

Thermal Hysteresis ◽

Hybrid Powertrain ◽

Actual Performance ◽

Wheel Loader ◽

Accumulator Model ◽

Hydraulic Hybrid ◽

Dynamic Simulation Model ◽

The Difference ◽

Hydraulic Accumulator ◽

Accumulator Models

Abstract Owing to its high power density, hydraulic hybrid is considered as an effective approach to reducing the fuel consumption of heavy duty vehicles. A gas-charged hydraulic accumulator serves as the power buffer, storing and releasing hydraulic power through gas. An accurate hydraulic accumulator model is crucial to predict its actual performance. There are two widely used accumulator models: isothermal and adiabatic models. Neither of these models are practical to reflect its real performance in the hydraulic hybrid system. Therefore, the influence of an accumulator model considering thermal hysteresis on a hydraulic hybrid wheel loader has been studied in this paper. The difference of three accumulator models (isothermal, adiabatic and energy balance) has been identified. A dynamic simulation model of the hydraulic hybrid wheel loader has been developed. The fuel consumptions of the hydraulic hybrid wheel loader with three accumulator models has been compared. The influence of heat transfer coefficient of the accumulator housing has also been studied.

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Linear Deterministic Accumulator Models of Simple Choice

Frontiers in Psychology ◽

10.3389/fpsyg.2012.00292 ◽

2012 ◽

Vol 3 ◽

Cited By ~ 30

Author(s):

Andrew Heathcote ◽

Jonathon Love

Keyword(s):

Accumulator Models

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The Functional Anatomy of a Perceptual Decision in the Human Brain

Journal of Neurophysiology ◽

10.1152/jn.00364.2009 ◽

2010 ◽

Vol 103 (3) ◽

pp. 1179-1194 ◽

Cited By ~ 76

Author(s):

Andrew S. Kayser ◽

Bradley R. Buchsbaum ◽

Drew T. Erickson ◽

Mark D'Esposito

Keyword(s):

Decision Making ◽

Visual Motion ◽

Functional Anatomy ◽

Sensory Information ◽

Imaging Study ◽

Neural Circuitry ◽

Perceptual Decision Making ◽

Visuomotor Integration ◽

Perceptual Decision ◽

Accumulator Models

Our ability to make rapid decisions based on sensory information belies the complexity of the underlying computations. Recently, “accumulator” models of decision making have been shown to explain the activity of parietal neurons as macaques make judgments concerning visual motion. Unraveling the operation of a decision-making circuit, however, involves understanding both the responses of individual components in the neural circuitry and the relationships between them. In this functional magnetic resonance imaging study of the decision process in humans, we demonstrate that an accumulator model predicts responses to visual motion in the intraparietal sulcus (IPS). Significantly, the metrics used to define responses within the IPS also reveal distinct but interacting nodes in a circuit, including early sensory detectors in visual cortex, the visuomotor integration system of the IPS, and centers of cognitive control in the prefrontal cortex, all of which collectively define a perceptual decision-making network.

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Optimal evidence accumulation on social networks

10.1101/442848 ◽

2018 ◽

Author(s):

Bhargav Karamched ◽

Simon Stolarczyk ◽

Zachary Kilpatrick ◽

Kresimir Josić

Keyword(s):

Decision Making ◽

Social Information ◽

Network Connectivity ◽

Sufficient Evidence ◽

Decision Making Process ◽

Collective Decision Making ◽

Evidence Accumulation ◽

Forced Choice Task ◽

Social Cliques ◽

Accumulator Models

A fundamental question in biology is how organisms integrate sensory and social evidence to make decisions. However, few models describe how both these streams of information can be combined to optimize choices. Here we develop a normative model for collective decision making in a network of agents performing a two-alternative forced choice task. We assume that rational (Bayesian) agents in this network make private measurements, and observe the decisions of their neighbors until they accumulate sufficient evidence to make an irreversible choice. As each agent communicates its decision to those observing it, the flow of social information is described by a directed graph. The decision-making process in this setting is intuitive, but can be complex. We describe when and how the absence of a decision of a neighboring agent communicates social information, and how an agent must marginalize over all unobserved decisions. We also show how decision thresholds and network connectivity affect group evidence accumulation, and describe the dynamics of decision making in social cliques. Our model provides a bridge between the abstractions used in the economics literature and the evidence accumulator models used widely in neuroscience and psychology.

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The Neurodynamic Decision Variable in Human Multi-alternative Perceptual Choice

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01347 ◽

2019 ◽

Vol 31 (2) ◽

pp. 262-277 ◽

Cited By ~ 3

Author(s):

Carmen Kohl ◽

Laure Spieser ◽

Bettina Forster ◽

Sven Bestmann ◽

Kielan Yarrow

Keyword(s):

Sequential Sampling ◽

Human Action ◽

Corticospinal Excitability ◽

Decision Variable ◽

Dynamic Changes ◽

Baseline Activity ◽

Decision Alternative ◽

Response Alternatives ◽

Action Representations ◽

Accumulator Models

The neural dynamics underpinning binary perceptual decisions and their transformation into actions are well studied, but real-world decisions typically offer more than two response alternatives. How does decision-related evidence accumulation dynamically influence multiple action representations in humans? The heightened conservatism required in multiple compared with binary choice scenarios suggests a mechanism that compensates for increased uncertainty when multiple choices are present by suppressing baseline activity. Here, we tracked action representations using corticospinal excitability during four- and two-choice perceptual decisions and modeled them using a sequential sampling framework. We found that the predictions made by leaky competing accumulator models to accommodate multiple choices (i.e., reduced baseline activity to compensate increased uncertainty) were borne out by dynamic changes in human action representations. This suggests a direct and continuous influence of interacting evidence accumulators, each favoring a different decision alternative, on downstream corticospinal excitability during complex choice.

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Toward a “Standard Model” of Early Language Learning

10.31234/osf.io/yhrb4 ◽

2021 ◽

Author(s):

George Kachergis ◽

Virginia A. Marchman ◽

Michael C. Frank

Keyword(s):

Standard Model ◽

Language Learning ◽

Learning Outcomes ◽

Item Response ◽

Computational Models ◽

Empirical Work ◽

Individual Variability ◽

Early Language ◽

Accumulator Models ◽

Item Response Theory Models

A "standard model" is a theoretical framework that synthesizes observables into a quantitative consensus. Have we made progress towards this kind of synthesis for children’s early language learning? Many computational models of early vocabulary learning assume that individual words are learned through an accumulation of environmental input. This assumption is also implicit in empirical work that emphasizes links between language input and learning outcomes. However, models have typically focused on average performance, while empirical work has focused on variability. To model individual variability, we relate the tradition of research on accumulator models to Item-Response Theory models from psychometrics. This formal connection reveals that currently available datasets cannot allow us to fully test these models, illustrating a critical need for theory in shaping new data collection and in creating and testing an eventual "standard model."

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