Computational modeling plays an important role in prediction and optimization of real systems and processes. Models usually have some parameters which should be set up to the proper value. Therefore, parameter estimation is known as an important part of the modeling and system identification. It usually refers to the process of using sampled data to estimate the optimum values of parameters. The accuracy of model can be increased by adjusting its parameters to the optimum value which need (...) a richer dataset. One simple solution for having a richer dataset is increasing the amount of data, but that can be costly and time consuming. When using data from animals or people, it is especially important to have a proper plan. There are several available methods for parameter estimation in dynamical systems; however there are some basic differences in chaotic systems due to their sensitivity to initial condition. Accordingly, in this paper, a new cost function which is proper for chaotic systems is applied to the chaotic one-dimensional map. Then the efficiency of a newly introduced intelligent method experimental design in extracting proper data is investigated. The results show the success of the proposed method. (shrink)

Summary Analogue models are actual physical setups used to model something else. They are especially useful when what we wish to investigate is difficult to observe or experiment upon due to size or distance in space or time: for example, if the thing we wish to investigate is too large, too far away, takes place on a time scale that is too long, does not yet exist or has ceased to exist. The range and variety of analogue models is too (...) extensive to attempt a survey. In this article, I describe and discuss several different analogue model experiments, the results of those model experiments, and the basis for constructing them and interpreting their results. Examples of analogue models for surface waves in lakes, for earthquakes and volcanoes in geophysics, and for black holes in general relativity, are described, with a focus on examining the bases for claims that these analogues are appropriate analogues of what they are used to investigate. A table showing three different kinds of bases for reasoning using analogue models is provided. Finally, it is shown how the examples in this article counter three common misconceptions about the use of analogue models in physics. (shrink)

Parametric cognitive models are increasingly popular tools for analyzing data obtained from psychological experiments. One of the main goals of such models is to formalize psychological theories using parameters that represent distinct psychological processes. We argue that systematic quantitative reviews of parameter estimates can make an important contribution to robust and cumulative cognitive modeling. Parameter reviews can benefit model development and model assessment by providing valuable information about the expected parameter space, and can facilitate the more efficient design of (...) experiments. Importantly, parameter reviews provide crucial—if not indispensable—information for the specification of informative prior distributions in Bayesian cognitive modeling. From the Bayesian perspective, prior distributions are an integral part of a model, reflecting cumulative theoretical knowledge about plausible values of the model's parameters (Lee,2018). In this paper we illustrate how systematic parameter reviews can be implemented to generate informed prior distributions for the Diffusion Decision Model (DDM; Ratcliff and McKoon,2008), the most widely used model of speeded decision making. We surveyed the published literature on empirical applications of the DDM, extracted the reported parameter estimates, and synthesized this information in the form of prior distributions. Our parameter review establishes a comprehensive reference resource for plausible DDM parameter values in various experimental paradigms that can guide future applications of the model. Based on the challenges we faced during the parameter review, we formulate a set of general and DDM-specific suggestions aiming to increase reproducibility and the information gained from the review process. (shrink)

My paper draws on examples from molecular biology, the details of which I have developed elsewhere (Rheinberger 1992, 1993, 1995, 1997). Here, I can give only a brief outline of my argument. Reduction of complexity is a prerequisite for experimental research. To make sense of the universe of living beings, the modern biologist is bound to divide his world into fragments in which parameters can be defined, quantities measured, qualities identified. Such is the nature of any "experimental (...) system." Ontic complexity has to be reduced in order to make experimental research possible. The complexity of the research object, however, is epistemically retained in the rich context of an experimental landscape, where the eruption of "volcanic systems" can change the scenery dramatically as the result of particular, unprecedented findings. (shrink)

Computer simulations are nowadays often directly involved in the generation of experimental results. Given this dependency of experiments on computer simulations, that of simulations on models, and that of the models on free parameters, how do researchers establish trust in their experimental results? Using high-energy physics (HEP) as a case study, I will identify three different types of robustness that I call conceptual, methodological, and parametric robustness, and show how they can sanction this trust. However, as I (...) will also show, simulation models in HEP themselves fail to exhibit a type of robustness I call inverse parametric robustness. This combination of robustness and failures thereof is best understood by distinguishing different epistemic capacities of simulations and different senses of trust: Trusting simulations in their capacity to facilitate credible experimental results can mean accepting them as means for generating belief in these results, while this need not imply believing the models themselves in their capacity to represent an underlying reality. (shrink)

An innovative, multifaceted approach to scientific experiments as designed by and shaped through interaction with the modeling process The role of scientific modeling in mediation between theories and phenomena is a critical topic within the philosophy of science, touching on issues from climate modeling to synthetic models in biology, high energy particle physics, and cognitive sciences. Offering a radically new conception of the role of data in the scientific modeling process as well as a new awareness of the problematic aspects (...) of data, this cutting-edge volume offers a multifaceted view on experiments as designed and shaped in interaction with the modeling process. Contributors address such issues as the construction of models in conjunction with scientific experimentation; the status of measurement and the function of experiment in the identification of relevant parameters; how the phenomena under study are reconceived when accounted for by a model; and the interplay between experimenting, modeling, and simulation when results do not mesh. Highlighting the mediating role of models and the model-dependence of data measurement, this volume proposes a normative and conceptual innovation in scientific modeling--that the phenomena to be investigated and modeled must not be precisely identified at the start but specified during the course of the interactions arising between experimental and modeling activities. Contributors: Nancy D. Cartwright, U of California, San Diego; Anthony Chemero, U of Cincinnati; Ronald N. Giere, U of Minnesota; Jenann Ismael, U of Arizona; Tarja Knuuttila, U of South Carolina; Andrea Loettgers, U of Bern, Switzerland; Deborah Mayo, Virginia Tech; Joseph Rouse, Wesleyan U; Paul Teller, U of California, Davis; Michael Weisberg, U of Pennsylvania; Eric Winsberg, U of South Florida. (shrink)

Millions of animals are used every year in oftentimes extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the “3Rs” concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. (...) The licensing of animal experiments normally requires an ethical evaluation process, oftentimes undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees’ members. (shrink)

H. Collins has challenged the empiricist understanding of experimentation by identifying what he thinks constitutes the experimenter’s regress: an instrument is deemed good because it produces good results, and vice versa. The calibration of an instrument cannot alone validate the results: the regressive circling is broken by an agreement essentially external to experimental procedures. In response, A. Franklin has argued that calibration is a key reasonable strategy physicists use to validate production of results independently of their interpretation. The physicists’ (...) arguments about the merits of calibration are not coextensive with the interpretation of results, and thus an objective validation of results is possible. I argue, however, that the in-situ calibrating and measurement procedures and parameters at the Large Hadron Collider are closely and systematically interrelated. This requires empiricists to question their insistence on the independence of calibration from the outcomes of the experiment and rethink their position. Yet this does not leave the case of in-situ calibration open to the experimenter’s regress argument; it is predicated on too crude a view of the relationship between calibration and measurement that fails to capture crucial subtleties of the case. (shrink)

Model validation in computational cognitive psychology often relies on methods drawn from the testing of theories in experimental physics. However, applications of these methods to computational models in typical cognitive experiments can hide multiple, plausible sources of variation arising from human participants and from stochastic cognitive theories, encouraging a “model fixed, data variable” paradigm that makes it difficult to interpret model predictions and to account for individual differences. This article proposes a likelihood‐based, “data fixed, model variable” paradigm in which (...) models are treated as stochastic processes in experiments with participant‐to‐participant variation that can be applied to a broad range of mechanistic cognitive architectures. This article discusses the implementation and implications of this view in model validation, with a concrete focus on a simple class of ACT‐R models of cognition. This article is not intended as a recipe for broad application of these preliminary, proof‐of‐concept methods, but as a framework for communication between statisticians searching for interesting problems in the cognitive modeling sphere, and cognitive modelers interested in generalizing from deterministic to stochastic model validation, in the face of random variation in human experimental data. (shrink)

The following investigates the work of the still too neglected thinker Gilles Châtelet with a particular emphasis on how his understanding of intuition functions across philosophy, science, and mathematics. The question is whether intuition (as Châtelet understands in a generally Schellingian formulation) trivializes the processes of scientific and mathematical thought subjecting them to an experimental errancy of chance. While it is common to dismiss Schelling’s notion of intellectual intuition as god-like knowledge following Kant, even a cursory examination of how (...) Schelling uses the term throughout his career, and how it relates to other forms, demonstrates that intuition is more of an experimental immediacy that is imperfectly conceptually laden yet effective. Though Schelling is often considered an anti-formal or anti logical thinker (at least in contradistinction to Hegel) this is surely not the case if one allows the diagram to be considered as formal as the statement of logic. For Châtelet, Schelling’s philosophy of powers is what allows for a suspension of things in such a manner that necessitates understanding the map of nature in terms of vectors, lines, and fields. What immediately comes into question is the status of this expanded notion of the formal vis a vis the metaphysical and of the egress of thought into nature and nature into thought. (shrink)

There has been relatively little effort to provide a systematic overview of different forms of exploratory experimentation (EE). The present paper examines the growing subdiscipline of nanotoxicology and suggests that it illustrates at least four ways that researchers can engage in EE: searching for regularities; developing new techniques, simulation models, and instrumentation; collecting and analyzing large swaths of data using new experimental strategies (e.g., computer-based simulation and "high-throughput" instrumentation); and structuring an entire disciplinary field around exploratory research agendas. In (...) order to distinguish these and other activities more effectively, the paper proposes a taxonomy that includes three dimensions along which types of EE vary: (1) the aim of the experimental activity, (2) the role of theory in the activity, and (3) the methods or strategies employed for varying experimental parameters. (shrink)

The view is advocated that to preserve a deductivist account of science against recent criticism, it is necessary to incorporate experimental error, or imprecision, in the deductive structure. The sources of imprecision in empirical variables are analyzed, and the notion of conceptual imprecision introduced and illustrated. This is then used to clarify the notion of the acceptable range of a functional law. It is further shown that imprecision may be ascribed to parameters in laws and theories without rendering (...) the deductive structure untestable. It is claimed that this analysis explicates the relation between laws and theories in a way that invalidates certain arguments against its deductive nature. (shrink)

For a variety of reasons, including the common use of deception in psychology experiments, participants often disbelieve experimenters' assertions about important task parameters. This can lead researchers to conclude incorrectly that participants are behaving non- normatively. The problem can be overcome by deriving and testing normative models that do not assume full belief in key task parameters. A real experimental example is discussed.

This paper discusses methodological issues of two recent experiments conducted by Christopher Bartel, and Elzė S. Mikalonytė and Vilius Dranseika, respectively, about the repeatability and individuation of musical works. I argue, first, that the reliability of their results about people’s intuitions in our everyday musical practices can be questioned due to the use of descriptions instead of musical stimuli of the works and performances involved in the cases tested. This procedure is prone to place participants in an epistemic situation in (...) which their mental capacities for their everyday judgments are not deployed and makes their judgments more vulnerable to the problem of “filling in”. I provide empirical data of an experiment that implements musical stimuli, obtaining large effect sizes regarding the results obtained by Bartel, Mikalonytė and Dranseika. In addition, I argue that the results of three scenarios of the experiment conducted by Mikalonytė and Dranseika are suspicious of being influenced by presentation effects that favor the contextualist intuition that the composer is a relevant parameter in work-individuation. Formal and superficial aspects of the description of their cases would cause these effects. I supply empirical data of an experiment that neutralizes those effects, obtaining moderate and large effect sizes regarding the results of Mikalonytė and Dranseika. (shrink)

While Kant introduces his critical philosophy in continuity with the experimental tradition begun by Francis Bacon, it is widely accepted that his Copernican revolution places experimental physics outside the bounds of science. Yet scholars have recently contested this view. They argue that in Critique of the Power of Judgment Kant’s engagement with the growing influence of vitalism in the 1780s leads to an account of nature’s formative power that returns experimental physics within scientific parameters. Several critics (...) are sceptical of this revised reading. They argue that Kant’s third Critique serves precisely to deflate the epistemological status of experimental physics, thereby protecting science from the threat of vitalism. In this paper I examine Kant’s account of science in the context of the experimental tradition of philosophy, particularly in relation to the generation dilemma of the eighteenth century. I argue that Kant does not deflate the epistemological status of experimental physics but rather introduces systematicity to the experimental tradition. By identifying the reflective use of reason to organize laws of experience into a systematic whole, Kant aims to ground experimental inquiry on the secure course of a science, opening a conception of science as a research programme. (shrink)

In this paper we give additional arguments in favor of the point of view that the violation of Bell, CHSH and CH inequalities is not due to a mysterious non locality of nature. We concentrate on an intimate relation between a protocol of a random experiment and a probabilistic model which is used to describe it. We discuss in a simple way differences between attributive joint probability distributions and generalized joint probability distributions of outcomes from distant experiments which depend on (...) how the pairing of these outcomes is defined. We analyze in detail experimental protocols implied by local realistic and stochastic hidden variable models and show that they are incompatible with the protocols used in spin polarization correlation experiments. We discuss also the meaning of “free will”, differences between quantum and classical filters, contextuality of Kolmogorov models, contextuality of quantum theory and show how this contextuality has to be taken into account in probabilistic models trying to explain in an intuitive way the predictions of QT. The long range imperfect correlations between the clicks of distant detectors can be explained by partially preserved correlations between the signals created by a source. These correlations can only be preserved if the clicks are produced in a local and deterministic way depending on intrinsic parameters describing signals and measuring devices in the moment of the measurement. If an act of a measurement was irreducibly random they would be destroyed. It seems to indicate that QT may be in fact emerging from some underlying more detailed theory of physical phenomena. If this was a case then there is a chance to find in time series of experimental data some fine structures not predicted by QT. This would be a major discovery because it would not only prove that QT does not provide a complete description of individual physical systems but it would prove that it is not predictably complete. (shrink)

This paper is intended as an extension to some of the recent discussion in the philosophical literature on the nature of experimental evidence. In particular I examine the role of empirical evidence attained through the use of deductions from phenomena. This approach to theory construction has been widely used throughout the history of science both by Newton and Einstein as well as Clerk Maxwell. I discuss a particular formulation of maxwell's electrodynamics, one he claims was deduced from experimental (...) facts. However, the deduction is problematic in that it is not immediately clear that one of the crucial parameters of the theory, the displacement current, can be given an empirical foundation. In outlining Maxwell's argument and his attempts to arrive on an empirically based account of the electromagnetic field equations I draw attention to the philosophical implications of the constraints on theory that arise in this particular case of deduction from phenomena. (shrink)

The subjective features of psychological phenomena have been studied intensively in experimental science in recent years. Although various methods have been proposed to identify subjective features of psychological phenomena, there are elusive subjective features such as the spatiotemporal structure of experience, which are difficult to capture without some additional methodological tools. We propose a new experimental method to address this challenge, which we call the contrast-based experimental phenomenological method (CEP). CEP proceeds in four steps: (i) front-loading phenomenology, (...) (ii) online second-personal interview, (iii) questionnaire survey, and (iv) hypotheses testing. It differs from other experimental phenomenological methods in that it takes advantage of phenomenal contrasts in collecting phenomenological data. In this paper, we verify the validity and productivity of this method by applying it to binocular rivalry (BR). The study contributes to empirical research on BR in three respects. First, it provides additional evidence for existing propositions about the subjective features of BR: e.g. the proposition that the temporal dynamics of the experience depend upon subject-dependent parameters such as attentional change. Second, it deepens our understanding of the spatiotemporal structures of the transition phase of BR. Third, it elicits new research questions about depth experience and individual differences in BR. The presence of such contributions demonstrates the validity and productivity of CEP. (shrink)

Along three measurements at the Large Hadron Collider (LHC), a high energy particle accelerator, we analyze procedures and consequences of exploratory experimentation (EE). While all of these measurements fulfill the requirements of EE: probing new parameter spaces, being void of a target theory and applying a broad range of experimental methods, we identify epistemic differences and suggest a classification of EE. We distinguish classes of EE according to their respective goals: the exploration where an established global theory cannot provide (...) the details of a local phenomenon, exploration of an astonishing discovery and exploration to find a new entity. We find that these classes also differ with respect to the existence of an identifiable target and their impact on the background theory. The characteristics distinguish EE from other kinds of experimentation, even though these different kinds have not yet been systematically studied. The formal rigor and precision of LHC physics facilitates to analyze concept formation in its early state. In particular we emphasize the importance for nil–results for conceptualization and argue that conceptualization can also be achieved from nil–results only. (shrink)

Several key areas in modeling the cardiovascular and respiratory control systems are reviewed and examples are given which reflect the research state of the art in these areas. Attention is given to the interrelated issues of data collection, experimental design, and model application including model development and analysis. Examples are given of current clinical problems which can be examined via modeling, and important issues related to model adaptation to the clinical setting.

The elastic and radiative π + p scattering are studied in the framework of an effective Lagrangian model for the Δ ++ resonance and its interactions. The finite width effects of this spin-3/2 resonance are introduced in the scattering amplitudes through a complex mass scheme to respect electromagnetic gauge invariance. The resonant pole (Δ ++) and background contributions (ρ 0, σ, Δ, and neutron states) are separated according to the principles of the analytic S-matrix theory. The mass and width (...) class='Hi'>parameters of the Δ ++ obtained from a fit to experimental data on the total cross section are in agreement with the results of a model-independent analysis based on the analytic S-matrix approach. The magnetic dipole moment determined from the radiative π + p scattering is $\mu _{\Delta ^{ + + } } = (6.14 \pm 0.51)$ nuclear magnetons. (shrink)

In this paper, we propose an adaptive Gaussian incremental expectation stadium parameter estimation algorithm for sports video analysis and prediction through the study and analysis of sports videos. The features with more discriminative power are selected from the set of positive and negative templates using a feature selection mechanism, and a sparse discriminative model is constructed by combining a confidence value metric strategy. The sparse generative model is constructed by combining L1 regularization and subspace representation, which retains sufficient representational power (...) while dealing with outliers. To overcome the shortcomings of the traditional multiplicative fusion mechanism, this paper proposes an adaptive selection mechanism based on Euclidean distance, which aims to detect deteriorating models in time during the dynamic tracking process and adopt corresponding strategies to construct more reasonable likelihood functions. Based on the Bayesian citation framework, the adaptive selection mechanism is used to combine the sparse discriminative model and the sparse generative model. Also, different online updating strategies are adopted for the template set and Principal Component Analysis subspace to alleviate the drift problem while ensuring that the algorithm can adapt to the changes of target appearance in the dynamic tracking environment. Through quantitative and qualitative evaluation of the experimental results, it is verified that the algorithm proposed in this paper has stronger robustness compared with other classical algorithms. Our proposed visual object tracking algorithm not only outperforms existing visual object tracking algorithms in terms of accuracy, success rate, accuracy, and robustness but also achieve the performance required for real-time tracking in terms of execution speed on the central processing unit. This paper provides an in-depth analysis and discussion of the adaptive Gaussian incremental expectation stadium parameter estimation algorithm for sports video analysis. Using a variety of county-level algorithms for analysis and multiple solutions to improve the accuracy of the results, we obtain a more efficient and accurate algorithm. (shrink)

The aim of this research is focused on analyzing the alteration of the psychophysiological and cognitive response to an objective computerized stress test, when the behavioral response is controlled. The sample used was sports science students, with a mean age of 22.82 A quasi-experimental design was used in which the response of each participant to the DT test was evaluated. The variable “number of hours of physical activity per week” and the variable “level of behavioral response to stress” were (...) controlled. Before and after this test, the following parameters were measured: activation and central fatigue, and perceived exertion. Significant differences were found in all of the measures indicated. The usefulness of this protocol and the measures used to analyze the stress response capacity of the study subjects are discussed. (shrink)

In the face of continuing assumptions by many scientists and journal editors that p-values provide a gold standard for inference, counter warnings are published periodically. But the core problem is not with p-values, per se. A finding that “p-value is less than α” could merely signal that a critical value has been exceeded. The question is why, when estimating a parameter, we provide a range (a confidence interval), but when testing a hypothesis about a parameter (e.g. µ = x) we (...) proceed as if “=” entails exact equality of the parameter with x. That standard is hard to meet, and is not a standard expected for power calculations, where we are satisfied to reject a null hypothesis H0 if the result is merely “detectably” different from (exact) H0. This paper explores, with resampling (simulation) methods, the impacts on p-values, and alternatives, if the null hypothesis is defined as a thick or thin range of values. It also examines, empirically, the extent to which the p-value may or may not be a good predictor of the probability that H0 is true, given the distribution of the data. (shrink)

There is evidence that bidders fall prey to the winner’s curse because they fail to extract information from hypothetical events—like winning an auction. This paper investigates experimentally whether bidders in a common value auction perform better when the requirements for this cognitive issue—also denoted by contingent reasoning—are relaxed, leaving all other parameters unchanged. For my underlying research question, I used a lab experiment with two stages. In stage I, the subjects participate in a non-standard common value auction, called the (...) wallet game, in which a naïve bidding strategy can lead to both winner’s curse and loser’s curse. In stage II, the subjects in the treatment group learn whether their initial bid was the winning bid or not and they get the opportunity to change this bid. In this sense, the bidders face the same decision problems as in stage I again, but the need for hypothetical thinking is reduced in stage II. The overall pattern of the data suggests that the problem of irrational over- and underbidding can be weakened by giving the subjects ex ante feedback about their bid, but unlike related studies I also find negative effects of additional information. (shrink)

This paper is expected to introduce a novel memductor-based chaotic system. The local dynamical entities, such as the basic dynamical behavior, the divergence, the stability of equilibrium set, and the Lyapunov exponent, are all investigated analytically and numerically to reveal the dynamic characteristics of the new memductor-based chaotic system as the system parameters and the initial state of memristor change. Subsequently, an active control method is derived to study the synchronous stability of the novel memductor-based chaotic system through making (...) the synchronization error system asymptotically stable at the origin. Further to these, a memductor-based chaotic circuit is designed, realized, and applied to construct a new memductor-based secure communication circuit by employing the basic electronic components and memristor. Furthermore, the design principle of the memductor-based chaotic circuit is thoroughly analyzed and the concept of “the memductor-based chaotic circuit defect quantification index” is proposed for the first time to verify whether the chaotic output is consistent with the mathematical model. A good qualitative agreement is shown between the simulations and the experimental validation results. (shrink)

This paper attempts to identify behavioral patterns and compare their average success considering several criteria of bounded rationality. Experimentally observed choice behavior in various decision tasks is used to assess heterogeneity in how individual participants respond to 15 randomly ordered portfolio choices, each of which is experienced twice. Treatments differ in granting probability information and in eliciting aspirations. Since in our setting neither other regarding concerns nor risk attitude matter and probability of the binary chance move is choice irrelevant, categorizing (...) decision types relies on parameter dependence and choice adaptations. We find that most participants reduce systematically sub-optimality when following the identified criteria. (shrink)

To what extent, if any, does Universal Grammar (UG) constrain second language (L2) acquisition? This is not only an empirical question, but one which is currently investigable. In this context, L2 acquisition is emerging as an important new domain of psycholinguistic research. Three logical possibilities have been articulated regarding the role of UG in L2 acquisition: The first is the hypothesis that claims that no aspect of UG is available to the L2 learner. The second is the hypothesis that claims (...) that only LI instantiated principles and LI instantiated parameter-values of UG are available to the learner. The third, called the hypothesis, asserts that UG in its entirety constrains L2 acquisition. (shrink)

Developmental models that account for the metabolic effect of temperature variability on poikilotherms, such as degree-day models, have been widely used to study organism emergence, range and development, particularly in agricultural and vector-borne disease contexts. Though simple and easy to use, structural and parametric issues can influence the outputs of such models, often substantially. Because the underlying assumptions and limitations of these models have rarely been considered, this paper reviews the structural, parametric, and experimental issues that arise when using (...) degree-day models, including the implications of particular structural or parametric choices, as well as assumptions that underlie commonly used models. Linear and non-linear developmental functions are compared, as are common methods used to incorporate temperature thresholds and calculate daily degree-days. Substantial differences in predicted emergence time arose when using linear versus non-linear developmental functions to model the emergence time in a model organism. The optimal method for calculating degree-days depends upon where key temperature threshold parameters fall relative to the daily minimum and maximum temperatures, as well as the shape of the daily temperature curve. No method is shown to be universally superior, though one commonly used method, the daily average method, consistently provides accurate results. The sensitivity of model projections to these methodological issues highlights the need to make structural and parametric selections based on a careful consideration of the specific biological response of the organism under study, and the specific temperature conditions of the geographic regions of interest. When degree-day model limitations are considered and model assumptions met, the models can be a powerful tool for studying temperature-dependent development. (shrink)

Sickle cell haemoglobin polymerization reduces erythrocyte deformability, causing deleterous vaso-occlusions. The double-nucleation model states that polymers grow from HbS aggregates, the nuclei, in solution , onto existing polymers . When linearized at initial HbS concentration, this model predicts early polymerization and its characteristic delay-time :591–610, 611–631, 1985). Addressing its relevance for describing complete polymerization, we constructed the full, non-linearized model . Here, we compare the simulated outputs to experimental progress curves . Within 10% from start, average root mean square (...) deviation between simulated and experimental curves is 0.04 ± 0.01 . Conversely, for complete progress curves, averaged rms is 0.48 ± 0.04. This figure is improved to 0.13 ± 0.01 by adjusting heterogeneous pathway parameters : the nucleus stability , and the fraction of polymer surface available for nucleation , from 5e−7, to 13 . Similar results are obtained at 37°C. We conclude that the physico-chemical description of heterogeneous nucleation warrants refinements in order to capture the whole HbS polymerization process. (shrink)

The linguistic complexity of words has largely been studied on the behavioral level and in experimental settings. Only little is known about the neural processes underlying it in uninstructed, spontaneous conversations. We built up a multimodal neurolinguistic corpus composed of synchronized audio, video, and electrocorticographic (ECoG) recordings from the fronto-temporo-parietal cortex to address this phenomenon based on uninstructed, spontaneous speech production. We performed extensive linguistic annotations of the language material and calculated word complexity using several numeric parameters. We (...) orthogonalized the parameters with the help of a linear regression model. Then, we correlated the spectral components of neural activity with the individual linguistic parameters and with the residuals of the linear regression model, and compared the results. The proportional relation between the number of consonants and vowels, which was the most informative parameter with regard to the neural representation of word complexity, showed effects in two areas: the frontal one was at the junction of the premotor cortex, the prefrontal cortex, and Brodmann area 44. The postcentral one lay directly above the lateral sulcus and comprised the ventral central sulcus, the parietal operculum and the adjacent inferior parietal cortex. Beyond the physiological findings summarized here, our methods may be useful for those interested in ways of studying neural effects related to natural language production and in surmounting the intrinsic problem of collinearity between multiple features of spontaneously spoken material. (shrink)

PurposeThe purpose of this study was to introduce an orthogonal experimental design to improve the efficiency of building and optimizing models for freezing of gait prediction.MethodsA random forest model was developed to predict FOG by using acceleration signals and angular velocity signals to recognize possible precursor signs of FOG. An OED was introduced to optimize the feature extraction parameters.ResultsThe main effects and interaction among the feature extraction hyperparameters were analyzed. The false-positive rate, hit rate, and mean prediction time (...) were 27%, 68%, and 2.99 s, respectively.ConclusionThe OED was an effective method for analyzing the main effects and interactions among the feature extraction parameters. It was also beneficial for optimizing the feature extraction parameters of the FOG prediction model. (shrink)

In this paper, we run a laboratory experiment to compare two mechanisms in a procurement setting: Right-of-First-Refusal where the incumbent supplier is granted a privileged position versus standard First-Price-Auction. To this end, we have subjects compete against a computerized agent programmed to behave in a risk-neutral way in a FPA, and in a ROFR auction where the “incumbent” bidder is the computer. In contrast with theory, we observe that on average bidders are slightly but significantly more aggressive under the ROFR (...) when their costs are such that they are predicted to behave identically under both auction procedures. For the sub-sample of subjects for whom we can estimate a CRRA parameter, we confirm the theoretical prediction that the buyer’s expected cost is larger in the ROFR if the newcomer is not sufficiently risk-averse. (shrink)