Peter Spirtes, Clark Glymour, Richard Scheines, Christopher Meek, S. Fineberg, E. Slate. Prediction and Experimental Design with Graphical Causal Models.

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 their theoretical and experimental reflections on the capacities and behaviours of living systems, neuroscientists often formulate generalizations about the behaviour of neural circuits. These generalizations are highly idealized, as they omit reference to the myriads of conditions that could perturb the behaviour of the modelled system in real-world settings. This article analyses an experimental investigation of the behaviour of place cells in the rat hippocampus, in which highly idealized generalizations were tested by comparing predictions flowing from (...) them with real-world experimental results. The aim of the article is to identify under what conditions even single prediction failures regarding the behaviour of single cells sufficed to reject highly idealized generalizations, and under what conditions prima facie counter-examples were deemed to be irrelevant to the testing of highly idealized generalizations. The results of this analysis may contribute to understanding how idealized models are tested experimentally in neuroscience and used to make reliable predictions concerning living systems in real-world settings. (shrink)

Building on the emotion-centered model of voluntary work behavior, this research tests the relations between leader narcissism, followers’ malicious and benign envy, and supervisor-targeted counterproductive work behavior. Results across five studies, two experimental studies, and two field surveys indicate that leader narcissism relates positively to followers’ negative emotions, which in turn mediates the positive relation between leader narcissism and supervisor-targeted CWB. Proposed negative relations between leader narcissism and positive emotions were only partly supported. Our findings advance the understanding of (...) envy and the detrimental impact of leader narcissism on organizational functioning. (shrink)

The experimental research paradigm lies at the core of empirical psychology. New data analytical and computational tools continually enrich its methodological arsenal, while the paradigm’s mission remains the testing of theoretical predictions and causal explanations. Predictions regarding experimental results necessarily point to the future. Once the data are collected, the causal inferences refer to a hypothesis now lying in the past. The experimental paradigm is not designed to permit strong inferences about particular incidents that occurred (...) before predictions were made. In contrast, historical research and scholarship in other humanities focus on this backward direction of inference. The disconnect between forward-looking experimental psychology and backward-looking historical (i.e., narrative) psychology is a challenge in the postmodern era, which can be addressed. To illustrate this possibility, I discuss three historical case studies in light of theory and research in contemporary psychology. (shrink)

Experimental semanticists have concluded that there is wide variation in referential intuitions among speakers, for it appears that some speakers display referential intuitions that are in line with descriptivism, whereas other speakers’ intuitions are in line with the predictions of the causal-historical picture. In this chapter, I first situate the debate by comparing descriptivist and non-descriptivist approaches to reference. After examining some of the experimental results, I argue that the tests conducted do not elicit data that are (...) relevant for semantic theorizing and, hence, that the results should not have an impact in the theory of reference. (shrink)

What principles and mechanisms allow humans to encode complex 3D information, and how can it be so fast, so accurately and so flexibly transformed into coordinated action? How do these processes work when developed to the limit of human physiological and cognitive capacity—as they are in high-speed sports, such as alpine skiing or motor racing? High-speed sports present not only physical challenges, but present some of the biggest perceptual-cognitive demands for the brain. The skill of these elite athletes is in (...) many ways an attractive model for studying human performance “in the wild”, and its neurocognitive basis. This article presents a framework theory for how these abilities may be realized in high-speed sports. It draws on a careful analysis of the case of the motorsport athlete, as well as theoretical concepts from: (1) cognitive neuroscience of wayfinding, steering, and driving; (2) cognitive psychology of expertise; (3) cognitive modeling and machine learning; (4) human-in-the loop modellling in vehicle system dynamics and human performance engineering; (5) experimental research (in the laboratory and in the field) on human visual guidance. The distinctive contribution is the way these are integrated, and the concept ofchunkingis used in a novel way to analyze a high-speed sport. The mechanisms invoked are domain-general, and not specific to motorsport or the use of a particular type of vehicle (or any vehicle for that matter); theegocentric chunking hypothesisshould therefore apply to any dynamic task that requires similar core skills. It offers a framework for neuroscientists, psychologists, engineers, and computer scientists working in the field of expert sports performance, and may be useful in translating fundamental research into theory-based insight and recommendations for improving real-world elite performance. Specific experimental predictions and applicability of the hypotheses to other sports are discussed. (shrink)

Experimental studies have suggested that variables such as aptness or conventionality are predictors of people’s preference for expressing a particular topic–vehicle pair as either a metaphor or a simile. In the present study, we investigated if such variables would also be predictive within a more naturalistic context, where other variables, such as the intention to include an explanation, may also influence people’s decision. Specifically, we investigated the production of metaphor and simile expressions on the Internet via the Google search (...) engine and checked for accompanying explanations, as well as the properties they expressed, to examine whether ratings such as aptness, conventionality, as well as participants’ own stated preference or the intention to produce an explanation, would predict which topic–vehicle pairs appeared more often as metaphor. We found that participants’ stated preference predicted metaphor dominance on the Internet, and that apt topic–vehicles occurred more often as metaphors. The explanations collected, however, occurred 82% of the time after similes, and familiar expressions were the most explained. Finally, comparing the properties expressed in these explanations to normed property lists, we found that simile explanations typically expressed a novel conception of the topic–vehicle relationship. Therefore, we found that Internet posters use metaphors to convey an apt relationship, as found in previous laboratory studies, but prefer using a simile frame when they want to express a relationship that readers will find novel. (shrink)

While Classical Logic (CL) used to be the gold standard for evaluating the rationality of human reasoning, certain non-theorems of CL—like Aristotle’s and Boethius’ theses—appear intuitively rational and plausible. Connexive logics have been developed to capture the underlying intuition that conditionals whose antecedents contradict their consequents, should be false. We present results of two experiments (total n = 72), the first to investigate connexive principles and related formulae systematically. Our data suggest that connexive logics provide more plausible rationality frameworks for (...) human reasoning compared to CL. Moreover, we experimentally investigate two approaches for validating connexive principles within the framework of coherence-based probability logic (Pfeifer & Sanfilippo, 2021). Overall, we observed good agreement between our predictions and the data, but especially for Approach 2. (shrink)

This paper provides new tools for philosophical argument analysis and fresh empirical foundations for ‘critical’ ordinary language philosophy. Language comprehension routinely involves stereotypical inferences with contextual defeaters. J.L. Austin’s Sense and Sensibilia first mooted the idea that contextually inappropriate stereotypical inferences from verbal case-descriptions drive some philosophical paradoxes; these engender philosophical problems that can be resolved by exposing the underlying fallacies. We build on psycholinguistic research on salience effects to explain when and why even perfectly competent speakers cannot help making (...) stereotypical inferences which are contextually inappropriate. We analyse a classical paradox about perception, suggest it relies on contextually inappropriate stereotypical inferences from appearance-verbs, and show that the conditions we identified as leading to contextually inappropriate stereotypical inferences are met in formulations of the paradox. Three experiments use a forced-choice plausibility-ranking task to document the predicted inappropriate inferences, in English, German, and Japanese. The cross-linguistic study allows us to assess the wider relevance of the proposed analysis. Our findings open up new perspectives for ‘evidential’ experimental philosophy. (shrink)

This study puts the usage-based assumption that our linguistic knowledge is based on usage to the test. To do so, we explore individual variation in speakers’ language use as established based on corpus data – both in terms of frequency of use and productivity of use – and link this variation to the same participants’ responses in an experimental judgment task. The empirical focus is on transfer by native German speakers living in the Netherlands, who oftentimes experience transfer from (...) their second language Dutch to their native language German regarding the placement of prepositional phrases. The analyses show a large amount of variation in both the corpus and experimental data with a strong link across data types: individual speakers’ usage – but not the usage by other speakers – is a significant predictor for the speakers’ judgments. These results strongly suggest that, in line with a usage-based approach, variation between speakers in experimental tasks is linked to their variation in usage. At the same time, such usage-based predictions do not explain all of the variation, suggesting that other individual factors are also at play in such experimental tasks. (shrink)

In this paper, we analyse higher-order risky choices by the representative cumulative prospect theory (CPT) decision maker from three alternative reference points. These are the status quo, average payout and maxmin. The choice tasks we consider in our analysis include binary risks, and are the ones employed in the experimental literature on higher order risk preferences. We demonstrate that the choices made by the representative subject depend on the reference point. If the reference point is the status quo and (...) the lottery choices exhibit symmetric risk, we demonstrate that there is no third order reflection effect of lottery choices but there is a fourth order reflection effect. When the average payout is the reference point, we demonstrate that any third or fourth order lottery choice is possible dependent upon the lottery payoffs. However, under the assumption of maxmin reference point, the risky choices are prudent and temperate. In addition to these results, our analysis reveals that the representative CPT subject can choose combinations of second with third and fourth order risky options that differ from those in other major models of decision under risk. We contrast our theoretical predictions with the empirical results reported in the literature on higher order risk preferences and are able to reconcile some conflicting experimental evidence. (shrink)

Twitter is a virtual social network where people share their posts and opinions about the current situation, such as the coronavirus pandemic. It is considered the most significant streaming data source for machine learning research in terms of analysis, prediction, knowledge extraction, and opinions. Sentiment analysis is a text analysis method that has gained further significance due to social networks’ emergence. Therefore, this paper introduces a real-time system for sentiment prediction on Twitter streaming data for tweets about the coronavirus pandemic. (...) The proposed system aims to find the optimal machine learning model that obtains the best performance for coronavirus sentiment analysis prediction and then uses it in real-time. The proposed system has been developed into two components: developing an offline sentiment analysis and modeling an online prediction pipeline. The system has two components: the offline and the online components. For the offline component of the system, the historical tweets’ dataset was collected in duration 23/01/2020 and 01/06/2020 and filtered by #COVID-19 and #Coronavirus hashtags. Two feature extraction methods of textual data analysis were used, n-gram and TF-ID, to extract the dataset’s essential features, collected using coronavirus hashtags. Then, five regular machine learning algorithms were performed and compared: decision tree, logistic regression, k-nearest neighbors, random forest, and support vector machine to select the best model for the online prediction component. The online prediction pipeline was developed using Twitter Streaming API, Apache Kafka, and Apache Spark. The experimental results indicate that the RF model using the unigram feature extraction method has achieved the best performance, and it is used for sentiment prediction on Twitter streaming data for coronavirus. (shrink)

The use of machine learning, or “artificial intelligence” (AI) in medicine is widespread and growing. In this paper, I focus on a specific proposed clinical application of AI: using models to predict incapacitated patients’ treatment preferences. Drawing on results from machine learning, I argue this proposal faces a special moral problem. Machine learning researchers owe us assurance on this front before experimental research can proceed. In my conclusion I connect this concern to broader issues in AI safety.

A thought experiment is reviewed which shows two things. First, in a region of a rotating frame that is not simply connected, the inertial forces can be canceled without completely canceling the inertial vector potential (whose curl determines the Coriolis force); second, the presence of this uncanceled potential can be detected in a quantum interference experiment. It is then argued that the thought experiment was realized in an earlier experiment involving a rotating superconductor, and that the experimental results confirm (...) the theoretical prediction. In this way, the first experimental verification of a physical effect due to a nonelectromagnetic potential in a force-free region is established. An analogous experiment for the gravitational vector potential is also discussed. Finally, it is pointed out that the close connection between electromagnetic and inertial vector potentials provides an intuitive way to make predictions about rotating superconductors. (shrink)

We investigate experimentally the relationship between risk and incentives in a principal–agent setting. In contrast to the existing empirical literature that describes such relationship as ‘tenuous’ or inconclusive, we find a clear negative relationship—supporting the prediction of the standard theoretical model. Specifically, we find that principals reduce the size of the offered piece rates with an increase in risk and instead provide positive fixed wages. Furthermore, we find no relationship between the variance in the performance and the effort choice of (...) the agent, and a strong positive relationship between the effort choice of the agents and the offered piece rates as well as fixed wage, suggesting positive reciprocity. Finally, we find evidence of social projection by the principals regarding the agents’ degree of risk aversion. (shrink)

In earlier work ( Cleland [2001] , [2002]), I sketched an account of the structure and justification of ‘prototypical’ historical natural science that distinguishes it from ‘classical’ experimental science. This article expands upon this work, focusing upon the close connection between explanation and justification in the historical natural sciences. I argue that confirmation and disconfirmation in these fields depends primarily upon the explanatory (versus predictive or retrodictive) success or failure of hypotheses vis-à-vis empirical evidence. The account of historical explanation (...) that I develop is a version of common cause explanation. Common cause explanation has long been vindicated by appealing to the principle of the common cause. Many philosophers of science (e.g., Sober and Tucker) find this principle problematic, however, because they believe that it is either purely methodological or strictly metaphysical. I defend a third possibility: the principle of the common cause derives its justification from a physically pervasive time asymmetry of causation (a.k.a. the asymmetry of overdetermination). I argue that explicating the principle of the common cause in terms of the asymmetry of overdetermination illuminates some otherwise puzzling features of the practices of historical natural scientists. (shrink)

Dans le cadre de leur démarche permanente d’innovation, les équipes de la protection juridique du groupe Covéa ont expérimenté les nouveaux outils dits « prédictifs » à l’appui des conseils qu’elles donnent au titre des litiges dont elles ont la gestion. Parmi les objectifs, mesurer leurs apports dans la perception par nos assurés de leurs chances de succès et risques de condamnation, afin de faciliter leur prise de décision sur les suites à donner à leur dossier, et bien sûr, préparer (...) de nouveaux services à leur attention. (shrink)

This paper offers an experimental test of a version of Rubinstein’s bargaining model in which the players’ discount factors are unequal. We find that learning, rationality, and fairness are all significant in determining the outcome. In particular, we find that a model of myopic optimization over time predicts the sign of deviations in the opening proposal from the final undiscounted agreement in the previous period rather well. To explain the amplitude of the deviations, we then successfully fit a perturbed (...) version of the model of myopic adjustment to the data that allows for a bias toward refusing inequitable offers. (shrink)

In order to solve the problem of unsmooth and inefficient human-computer interaction process in the information age, a method for human-computer interaction intention prediction based on electroencephalograph signals and eye movement signals is proposed. This approach is different from previous methods where researchers predict using data from human-computer interaction and a single physiological signal. This method uses the eye movements and EEG signals that clearly characterized the interaction intention as the prediction basis. In addition, this approach is not only tested (...) with multiple human-computer interaction intentions, but also takes into account the operator in different cognitive states. The experimental results show that this method has some advantages over the methods proposed by other researchers. In Experiment 1, using the eye movement signal fixation point abscissa Position X, fixation point ordinate Position Y, and saccade amplitude to judge the interaction intention, the accuracy reached 92%, In experiment 2, only relying on the pupil diameter, pupil size and fixed time, fixed time of eye movement signals can not achieve higher accuracy of the operator’s cognitive state, so EEG signals are added. The cognitive state was identified separately by combining the screened EEG parameters Rα/β with the eye movement signal pupil diameter and fixation time, with an accuracy of 91.67%. The experimental combination of eye movement and EEG signal features can be used to predict the operator’s interaction intention and cognitive state. (shrink)

Studies of group selection have been done with both natural and manipulated populations using plants, insects and birds. Group selection occurred in all studies and often the strength of group selection was equal to that of individual selection. Laboratory selection experiments resulted in the opposite response to individual selection than that predicted. Selection with plants for high leaf area resulted in plants with smaller leaf area and selection for high emigration rate in beetles produced lines with lower rates. The selected (...) traits included interactions among individuals. Theoretical studies have shown that genetically based interactions among individuals can interfere with individual selection. Evolution can be partitioned into selection and the response to selection. A response to selection requires genetic variation. Properties of group genetic structure for the natural populations are discussed. The experimental populations had controlled group structure and demonstrate that populations can respond to group selection under some genetic structures. (shrink)

Do free will beliefs influence moral judgments? Answers to this question from theoretical and empirical perspectives are controversial. This study attempted to replicate past research and offer theoretical insights by analyzing World Values Survey data from residents of 46 countries (n = 65,111 persons). Corroborating experimental findings, free will beliefs predicted intolerance of unethical behaviors and support for severe criminal punishment. Further, the link between free will beliefs and intolerance of unethical behavior was moderated by variations in countries’ institutional (...) integrity, defined as the degree to which countries had accountable, corruption-free public sectors. Free will beliefs predicted intolerance of unethical behaviors for residents of countries with high and moderate institutional integrity, but this correlation was not seen for countries with low institutional integrity. Free will beliefs predicted support for criminal punishment regardless of countries’ institutional integrity. Results were robust across different operationalizations of institutional integrity and with or without statistical control variables. (shrink)

The accommodation of evidence has been argued to be associated with several methodological problems that should prompt evaluators to lower their confidence in the accommodative theory. Accommodators may overfit their model to data (Hitchcock and Sober, Br J Philos Sci 55(1):1–34, 2004. https://doi.org/10.1093/bjps/55.1.1), hunt for (spurious) associations between variables (Mayo, Error and the growth of experimental knowledge. University of Chicago Press, Chicago, 1996, pp 294–318), or ‘fudge’ their theory in the effort to accommodate a particular datum (Lipton, Inference to (...) the best explanation. Routledge, London, 2004, pp. 164–183). The converse of accommodation, novel prediction, has been offered as a solution. If theorists novelly predict empirical results rather than accommodate those results, the potential risks of accommodation are avoided, and the theory warrants greater confidence. This paper evaluates if the problems of accommodation justify a preference for novel prediction over accommodation for evaluators of a scientific theory. I argue that there is currently insufficient evidence to conclude that the problems of accommodation result in a predictivist advantage in theory confirmation. Taking into consideration the disadvantages of novel prediction and the advantages of accommodation, the impact of further evidential factors, and recent scientific evidence about the consequences of novel prediction and accommodation, novel prediction and accommodation appear roughly on a par, or accommodation is even superior in the current context. (shrink)

Scientific hypotheses may either predict particular unknown facts or accommodate previously-known data. Although affirmed predictions are intuitively more rewarding than accommodations of established facts, opinions divide whether predictive hypotheses are also epistemically superior to accommodation hypotheses. This paper examines the contribution of predictive hypotheses to discoveries of several bio-molecular systems. Having all the necessary elements of the system known beforehand, an abstract predictive hypothesis of semiconservative mode of DNA replication was successfully affirmed. However, in defining the genetic code whose (...) biochemical basis was unclear, hypotheses were only partially effective and supplementary experimentation was required for its conclusive definition. Markedly, hypotheses were entirely inept in predicting workings of complex systems that included unknown elements. Thus, hypotheses did not predict the existence and function of mRNA, the multiple unidentified components of the protein biosynthesis machinery, or the manifold unknown constituents of the ubiquitin–proteasome system of protein breakdown. Consequently, because of their inability to envision unknown entities, predictive hypotheses did not contribute to the elucidation of cation theories remained the sole instrument to explain complex bio-molecular systems, the philosophical question of alleged advantage of predictive over accommodative hypotheses became inconsequential. (shrink)

Evidence that led to the hypothesis of a backwards referral of conscious sensory experiences in time, and the experimental tests of its predictions, is summarized. Criticisms of the data and the conclusion by Churchland that this hypothesis is untenable are analysed and found to be based upon misconceptions and faulty evaluations of facts and theory. Subjective referral in time violates no neurophysiological principles or data and is compatible with the theory of "mental" and "physical" correspondence.

According to evolutionary theory, emotions are psychological mechanisms that have evolved to enhance fitness in specific situations by motivating appropriate (adaptive) behavior. Taking this perspective, a previous study examined the relationship between mood and preference for natural environments. It reported that participants’ anxiety level was associated with a preference for landscapes offering what Appleton called "refuge," while participants’ anger and cheerfulness were both associated with a preference for landscapes offering what Appleton called "prospect." We attempted to replicate these results and (...) to improve on the study by experimentally manipulating mood. Using a between-subjects design, 80 participants were instructed to self-induce one of four moods: anger, sadness, anxiety, or joy. After the mood induction, they viewed fourteen landscape photographs and recorded the seven most preferred. It was hypothesized that subjects experiencing anger or joy would prefer landscapes rich in "prospect" features, whereas participants experiencing sadness or anxiety would prefer landscapes rich in "refuge" features. In contrast to the previous study, the predictions were not supported: artificially induced moods may not provide ecological validity as a test of the "mood as motivator" model; alternatively, the first study may have reported an alpha error. To see whether the model has practical value, we recommend a study of landscape preference using participants with clinically significant levels of mood dysphoria. (shrink)

It is shown that unavoidable uncertainties arising from the experimental conditions in which systems are prepared for Einstein-Podolsky-Rosen experiments severely limit the possibilities for prediction. In the example originally proposed by EPR, time measurements are necessary for precise position predictions. If the preparation is designed to make the timing errors negligible, the parameters chosen for the preparation fix minimum uncertainties in the predictions leaving the observer no choice in the matter. In the case of correlated spin measurements, (...) the preparation leaves the observer no control over the effect of the detector on the particles; the uncertainty of the previous condition of any one particle is so large that no (classical) prediction of the response of another detector is possible. Thus, there are as yet no proposed experiments which satisfy the conditions required by EPR—i.e., precise predictions which violate the uncertainty principle. (shrink)

Kinetic demixing in quaternary mixed oxides has not been investigated previously, either theoretically or experimentally. In this theoretical study, we derive simple and exact analytical expressions that describe the steady-state cation concentration profiles resulting from kinetic demixing in mixed oxides of the O type. The concentration profiles are expressed in terms of cation-vacancy exchange frequency ratios. We assume a random distribution of cations and make use of the Moleko-Allnatt exact sum-rule expression relating the phenomenological coefficients in the ternary random alloy (...) to the vacancy mechanism operative. We employ Monte Carlo simulation of kinetic demixing to verify the result of the analysis. We discuss how kinetic demixing profiles can be processed to obtain atom-vacancy exchange frequency ratios. We also discuss how atom-vacancy exchange frequencies themselves might be obtained from available diffusivities in the quaternary oxide. (shrink)

Unlike the physical sciences, sociology is frequently described as an interpretative non-experimental science. Comparative epistemology sheds new light on this claim. 1. Experimentation is not a constant character of the physical sciences; 2. Experimental hypothetical-deductive reasoning, including the test of predictions, is also practicable in sociology. The argument is developed by a detailed step-wise comparison of the prediction of light ray deviation within the Sun’s gravitational field made in 1919 (physics) and the prediction of 8% cosmopolitanism of (...) Cambridge University between 1250 and 1350 (sociology). Extensive analysis of regent masters’ prosopographic notes yields the result of 9.5 percent cosmopolitanism, which is close to the theoretical prediction. Au contraire des sciences physiques, la sociologie est souvent décrite comme une science interprétative et non-expérimentale. L’épistémologie apporte un éclairage nouveau sur cette position : 1) L’expérimentation n’est pas un trait constant des sciences physiques ; 2) Le raisonnement expérimental est également applicable en sociologie. L’argument est développé en comparant en détail le test de la prédiction d’une déviation des rayons lumineux dans un champ de gravitation effectué en 1919 et le test de la prédiction d’un taux de cosmopolitisme de 8 % de l’université de Cambridge dans la période 1250-1350. Le dépouillement des notices prosopographiques des maîtres régents donne un résultat de 9,5 % proche de la prédiction théorique initiale. (shrink)

BackgroundAlthough gait patterns disturbances are known to be related to cognitive decline, there is no consensus on the possibility of predicting one from the other. It is necessary to find the optimal gait features, experimental protocols, and computational algorithms to achieve this purpose.PurposesTo assess the efficacy of the Stable Sparse Classifiers procedure for discriminating young and healthy older adults, as well as healthy and cognitively impaired elderly groups from their gait patterns. To identify the walking tasks or combinations of (...) tasks and specific spatio-temporal gait features that allow the best prediction with SSC.MethodsA sample of 125 participants was studied. They underwent assessment with five neuropsychological tests that explore different cognitive domains. A summarized cognitive index, based on the Mahalanobis distance from normative data, was calculated. The sample was divided into three groups using k-means clustering of MDCog in addition to Age. The participants executed four walking tasks and their gait patterns, measured with a body-fixed Inertial Measurement Unit, were used to calculate 16 STGF and dual-task costs. SSC was then employed to predict which group the participants belonged to. The classification's performance was assessed using the area under the receiver operating curves and the stable biomarkers were identified.ResultsThe discrimination HE vs. MCI-E revealed that the combination of the easy dual-task and the fast walking task had the best prediction performance. The features related to gait variability and to the amplitude of vertical acceleration had the largest predictive power. SSC prediction accuracy was better than the accuracies obtained with linear discriminant analysis and support vector machine classifiers.ConclusionsThe study corroborated that the changes in gait patterns can be used to discriminate between young and healthy older adults and more importantly between healthy and cognitively impaired adults. A subset of gait tasks and STGF optimal for achieving this goal with SSC were identified, with the latter method superior to other classification techniques. (shrink)

While a simple information market lets one trade on the probability of each value of a single variable, a full combinatorial information market lets one trade on any combination of values of a set of variables, including any conditional or joint probability. In laboratory experiments, we compare the accuracy of simple markets, two kinds of combinatorial markets, a call market and a market maker, isolated individuals who report to a scoring rule, and two ways to combine those individual reports into (...) a group prediction. We consider two environments with asymmetric information on sparsely correlated binary variables, one with three subjects and three variables, and the other with six subjects and eight variables (and so 256 states). (shrink)

User location prediction in location-based social networks can predict the density of people flow well in terms of intelligent transportation, which can make corresponding adjustments in time to make traffic smooth, reduce fuel consumption, reduce greenhouse gas emissions, and help build a green cycle low-carbon transportation green system. This paper proposes a Markov chain position prediction model based on multidimensional correction. Firstly, extract corresponding information from the user’s historical check-in position sequence as a position-position conversion map. Secondly, the influence of (...) check-in period, space distance, and other factors on the position prediction is linearly weighted and merged with the position prediction of the n-order Markov chain to construct MDC-MCM. Finally, we conduct a comprehensive performance evaluation of MDC-MCM using the dataset collected from Brightkite. Experimental results show that compared with other advanced location prediction technologies, MDC-MCM achieves better location prediction results. (shrink)

Sub-Saharan emerging countries experience electrical shortages resulting in power rationing, which ends up hampering economic activities. This paper proposes an approach for very short-term blackout forecast in grid-tied PV systems operating in low reliability weak electric grids of emerging countries. A pilot project was implemented in Arusha-Tanzania; it mainly comprised of a PV-inverter and a lead-acid battery bank connected to the local electricity utility company, Tanzania Electric Supply Company Limited. A very short-term power outage prediction model framework based on a (...) hybrid random forest algorithm was developed using open-source Python machine learning libraries and using a dataset generated from the pilot project’s experimental microgrid. Input data sampled at a 15-minute interval included day of the month, weekday, hour, supply voltage, utility line frequency, and previous days’ blackout profiles. The model was composed of an adaptive similar day module that predicts 15 minutes ahead from a sliding window lookup table spanning 2 weeks prior to the prediction target day, after which ASD prediction was fused with RF prediction, giving a final optimised RF-ASD blackout prediction model. Furthermore, the efficacy analysis of the short-term blackout prediction of the formulated RF, ASD, and RF-ASD regression and classification algorithms was compared. Considering the stochastic nature of blackouts, their performance was found to be fair in short-term blackout predictions of the test site’s weak grid using limited input data from the point of coupling of the user. The models developed were only able to predict blackouts if they occurred frequently and contiguously, but they performed poorly if they were sparse or dispersed. (shrink)

The distinction between explanation and prediction has received much attention in recent literature, but the equally important distinction between explanation and description (or between prediction and description) remains blurred. This latter distinction is particularly important in the social sciences, where probabilistic models (or theories) often play dual roles as explanatory and descriptive devices. The distinction between explanation (or prediction) and description is explicated in the present paper in terms of information theory. The explanatory (or predictive) power of a probabilistic model (...) is identified with information taken from (or transmitted by) the environment (e.g., the independent, experimentally manipulated variables), while the descriptive power of a model reflects additional information taken from (or transmitted by) the data. Although information is usually transmitted by the data in the process of estimating parameters, it turns out that the number of free parameters is not a reliable index of transmitted information. Thus, the common practice of treating parameters as degrees-of-freedom in testing probabilistic models is questionable. Finally, this information-theoretic analysis of explanation, prediction, and description suggests ways of resolving some recent controversies surrounding the pragmatic aspects of explanation and the so-called structural identity thesis. (shrink)

The empirical basis for self-control in Dohsa-hou as it relates to effects on cognitive processes has been explored in a few studies of the Japanese psychotherapy, but not under standardized conditions with a strong predictive theory of control. This study reports on a series of experiments with the Dual Mechanisms of Control framework to clarify the possible regulatory mechanism of Dohsa-hou by focusing on shoulder movement, a key body movement task used by practitioners across applied settings. Cognitive control was operationalized (...) with the AX version of Continuous Performance Test paradigm for proactive control and a modified Stroop task paradigm for reactive control in a 3-arm parallel group trial study design. Healthy Japanese university students were assigned to a Dohsa-hou group that performed a shoulder movement task for few minutes, an active control group that performed a similar task, or a passive control group comprised of a resting condition. A total of 55 participants performed the AX-CPT and 57 participants performed the modified Stroop task before and after the group manipulation. In the AX-CPT, an increase in the error rate of AY trial from pre- to post-test was observed in the passive control group only, and found to be marginally higher in the passive control group relative to Dohsa-hou group at post-test. This indicated that Dohsa-hou moderated the activation of proactive control by repeated AX-CPT performance. The error rate of the Proactive Behavioral Index did not differ from zero at post-test only in the Dohsa-hou group, indicating flexible cognitive control. In the modified Stroop task, there was no difference between congruent and incongruent trials at post-test for the Dohsa-hou group only, indicating the facilitation of reactive control. The evidence for a balancing effect for the Dohsa-hou-based shoulder movement task indicates that clients experience a form of continuous self-monitoring, which might reduce mind-wandering from their focus on movement execution combined with iterative verbal feedback from the therapist. Overall, the results of the present study suggest that the self-regulatory mechanism promoted in clinical Dohsa-hou emphasizes guided shifts in attention to the reactive mode toward a balance of cognitive control. (shrink)