scholarly journals The reward-complexity trade-off in schizophrenia

2020 ◽  
Author(s):  
Samuel J. Gershman ◽  
Lucy Lai
Keyword(s):  
State Dependence ◽  
Cognitive Effort ◽  
Healthy Controls ◽  
Trade Off ◽  
Capacity Limit ◽  
The World ◽  
Empirical Trade ◽  
Lower Complexity ◽  
Optimal Reward ◽  
Theoretical Results

AbstractAction selection requires a policy that maps states of the world to a distribution over actions. The amount of memory needed to specify the policy (the policy complexity) increases with the state-dependence of the policy. If there is a capacity limit for policy complexity, then there will also be a trade-off between reward and complexity, since some reward will need to be sacrificed in order to satisfy the capacity constraint. This paper empirically characterizes the trade-off between reward and complexity for both schizophrenia patients and healthy controls. Schizophrenia patients adopt lower complexity policies on average, and these policies are more strongly biased away from the optimal reward-complexity trade-off curve compared to healthy controls. How-ever, healthy controls are also biased away from the optimal trade-off curve, and both groups appear to lie on the same empirical trade-off curve. We explain these findings using a cost-sensitive actor-critic model. Our empirical and theoretical results shed new light on cognitive effort abnormalities in schizophrenia.

Comparative docking of SARS-CoV-2 receptors antagonists from repurposing drugs

2020 ◽  
Author(s):  
Micael Davi Lima de Oliveira ◽  
Kelson Mota Teixeira de Oliveira
Keyword(s):  
World Health Organisation ◽  
World Health ◽  
Lung Cells ◽  
The Novel ◽  
High Modulation ◽  
Main Protease ◽  
The World ◽  
Novel Coronavirus ◽  
Viral Receptors ◽  
Theoretical Results

According to the World Health Organisation, until 16 June, 2020, the number of confirmed and notified cases of COVID-19 has already exceeded 7.9 million with approximately 434 thousand deaths worldwide. This research aimed to find repurposing antagonists, that may inhibit the activity of the main protease (Mpro) of the SARS-CoV-2 virus, as well as partially modulate the ACE2 receptors largely found in lung cells, and reduce viral replication by inhibiting Nsp12 RNA polymerase. Docking molecular simulations were performed among a total of 60 structures, most of all, published in the literature against the novel coronavirus. The theoretical results indicated that, in comparative terms, paritaprevir, ivermectin, ledipasvir, and simeprevir, are among the most theoretical promising drugs in remission of symptoms from the disease. Furthermore, also corroborate indinavir to the high modulation in viral receptors. The second group of promising drugs includes remdesivir and azithromycin. The repurposing drugs HCQ and chloroquine were not effective in comparative terms to other drugs, as monotherapies, against SARS-CoV-2 infection.

scholarly journals Weighted voting procedure having a unique blocker

2021 ◽  
Author(s):  
Sanjay Bhattacherjee ◽  
Palash Sarkar
Keyword(s):  
Weighted Voting ◽  
Trade Off ◽  
Voting Weights ◽  
Goods And Services ◽  
Voting Games ◽  
Formal Study ◽  
Theoretical Results

AbstractThe Goods and Services Tax (GST) Council of India has a non-conventional weighted voting procedure having a primary player who is a blocker and a set of secondary players. The voting weights are not fixed and are determined based on the subset of players which participate in the voting. We introduce the notion of voting schema to formally model such a voting procedure. Individual voting games arise from a voting schema depending on the subset of secondary players who participate in the voting. We make a detailed formal study of the trade-off between the minimal sizes of winning and blocking coalitions in the voting games that can arise from a voting schema. Finally, the GST voting procedure is assessed using the theoretical results leading to suggestions for improvement.

scholarly journals The aerodynamic puzzle of nasalized fricatives: Aerodynamic and perceptual evidence from Scottish Gaelic

2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Natasha Warner ◽  
Daniel Brenner ◽  
Jessamyn Schertz ◽  
Andrew Carnie ◽  
Muriel Fisher ◽  
...  
Keyword(s):  
Scottish Gaelic ◽  
Trade Off ◽  
Instrumental Data ◽  
The World ◽  
Perceptual Evidence ◽  
Better Than ◽  
Do So

AbstractScottish Gaelic is sometimes described as having nasalized fricatives (/ṽ/ distinctively, and [f̃, x̃, h̃], etc. through assimilation). However, there are claims that it is not aerodynamically possible to open the velum for nasalization while maintaining frication noise. We present aerodynamic data from 14 native Scottish Gaelic speakers to determine how the posited nasalized fricatives in this language are realized. Most tokens demonstrate loss of nasalization, but nasalization does occur in some contexts without aerodynamic conflict, e.g., nasalization with the consonant realized as an approximant, nasalization of [h̃], nasalization on the preceding vowel, or sequential frication and nasalization. Furthermore, a very few tokens do contain simultaneous nasalization and frication with a trade-off in airflow. We also present perceptual evidence showing that Gaelic listeners can hear this distinction slightly better than chance. Thus, instrumental data from one of the few languages in the world described as having nasalized fricatives confirms that the claimed sounds are not made by producing strong nasalization concurrently with clear frication noise. Furthermore, although speakers most often neutralize the nasalization, when they maintain it, they do so through a variety of phonetic mechanisms, even within a single language.

scholarly journals Validation of Discrete and Regression-Based Performance and Cognitive Fatigability Normative Data for the Paced Auditory Serial Addition Test in Multiple Sclerosis

2021 ◽  
Vol 15 ◽  
Author(s):  
Caitlin S. Walker ◽  
Jason A. Berard ◽  
Lisa A. S. Walker
Keyword(s):  
Multiple Sclerosis ◽  
Normative Data ◽  
Cognitive Effort ◽  
Similar Proportion ◽  
Healthy Controls ◽  
Performance Decrement ◽  
Impaired Performance ◽  
Objective Performance ◽  
Serial Addition ◽  
Over Time

Cognitive fatigability is an objective performance decrement that occurs over time during a task requiring sustained cognitive effort. Although cognitive fatigability is a common and debilitating symptom in multiple sclerosis (MS), there is currently no standard for its quantification. The objective of this study was to validate the Paced Auditory Serial Addition Test (PASAT) discrete and regression-based normative data for quantifying performance and cognitive fatigability in an Ontario-based sample of individuals with MS. Healthy controls and individuals with MS completed the 3″ and 2″ versions of the PASAT. PASAT performance was measured with total correct, dyad, and percent dyad scores. Cognitive fatigability scores were calculated by comparing performance on the first half (or third) of the task to the last half (or third). The results revealed that the 3″ PASAT was sufficient to detect impaired performance and cognitive fatigability in individuals with MS given the increased difficulty of the 2″ version. In addition, using halves or thirds for calculating cognitive fatigability scores were equally effective methods for detecting impairment. Finally, both the discrete and regression-based norms classified a similar proportion of individuals with MS as having impaired performance and cognitive fatigability. These newly validated discrete and regression-based PASAT norms provide a new tool for clinicians to document statistically significant cognitive fatigability in their patients.

The Rise, Fall and Rebirth of Foreign Policy Planning in Brazil (1949-2018)

2021 ◽  
pp. 1-19
Author(s):  
Rogério de Souza Farias
Keyword(s):  
Foreign Policy ◽  
Policy Making ◽  
Foreign Affairs ◽  
Policy Planning ◽  
Trade Off ◽  
External Relations ◽  
The World

Summary Policy planning has a long history in the Ministries of Foreign Affairs around the world. This article provides an overview of almost 70 years of this technique in Brazil’s Ministry of External Relations (Itamaraty). I will argue that there has been a clear trade-off between predicting, preaching, disrupting and managing. Despite its failures, planning has been an important tool for coping with uncertainty and has provided coherence in foreign policy-making.

scholarly journals IDENTIFIKASI KEPENTINGAN RELATIF KONSUMEN TERHADAP ROBOT REHABILITASI PASIEN PASCA STROKE DENGAN MENGGUNAKAN CONJOINT ANALYSIS

2017 ◽  
Vol 12 (1) ◽  
pp. 35
Author(s):  
Hasan Mastrisiswadi ◽  
Herianto Herianto
Keyword(s):  
Developing Country ◽  
Conjoint Analysis ◽  
Stroke Rehabilitation ◽  
Rehabilitation Robot ◽  
Relative Importance ◽  
Trade Off ◽  
Post Stroke ◽  
Trade Offs ◽  
The World

Robot rehabilitasi pasien pasca stroke saat ini telah dikembangkan oleh negara-negara maju di dunia, tidak terkecuali Indonesia meskipun sebagai negara berkembang. Salah satu pengembang robot rehabilitasi pasien pasca stroke itu berada di Universitas Gadjah Mada yang telah melakukan penelitian beberapa tahun ini. Penelitian ini bertujuan untuk mengidentifikasi kepentingan relatif konsumen terhadap robot rehabilitasi pasien pasca stroke untuk kemudian digunakan sebagai bahan masukan dalam pengembangan robot selanjutnya. Metode yang digunakan dalam penelitian ini adalah Conjoint Analysis. Metode ini memiliki keunggulan dalam menganalisis trade off antar atribut. Dari hasil pengolahan Conjoint Analysis dengan bantuan program SPSS, dapat diketahui bahwa kebutuhan konsumen paling tinggi terhadap robot rehabilitasi pasien stroke adalah  dapat dipasangkan ke tangan pasien dengan mudah, baru setelah itu kemampuannya untuk dipakai di kedua tangan (kanan dan kiri) dan material yang digunakan dalam pembuatan robot haruslah aman bagi pasien.AbstractPost-stroke rehabilitation robot has been developed in the world, including Indonesia as a developing country. One of this robot developers is Universitas Gadjah Mada who has conducted research for post stroke rehabilitation robot in recent years. This study aims to identify the consumer’s relative importance of the  post-stroke rehabilitation robot that can be used for the next robot development. The method used in this study is Conjoint Analysis. This method has the advantage in analyzing trade-offs between attributes. From this research, we have known that the highest rank of the robot consumer needs are: can be attached to the patient's hand with ease, the ability to be used in both hands (right and left) and the movement of the robot which can be varied according to the needs of the patient.

Optimal Number of Mobile Service Providers in India

2009 ◽  
pp. 2306-2322
Author(s):  
Rohit Prasad ◽  
Varadharajan Sridhar
Keyword(s):  
Economies Of Scale ◽  
Service Providers ◽  
Optimal Number ◽  
Policy Implications ◽  
Mobile Service ◽  
Trade Off ◽  
Unit Costs ◽  
Mobile Industry ◽  
The World ◽  
Mobile Subscriber

With 225 million subscribers, India has the world’s third largest mobile subscriber base in the world. The Indian mobile industry is also one of the most competitive in the world with 4-7 operators in each service area. A large number of operators bring competition and its associated benefits such as decrease in price and hence corresponding growth of the market. On the other hand in the presence of economies of scale, too many operators may result in inefficient scales and high unit costs. This article analyses the trade-off between competition and economies of scale by estimating the production function for mobile subscribers and traffic carried. Analysis of panel data reveals the existence of economies of scale in the Indian mobile sector. We then derive an upper bound on the optimal number of operators in each license area and discuss policy implications.

scholarly journals On the Complexity and Typology of Inflectional Morphological Systems

2019 ◽  
Vol 7 ◽  
pp. 327-342 ◽  
Author(s):  
Ryan Cotterell ◽  
Christo Kirov ◽  
Mans Hulden ◽  
Jason Eisner
Keyword(s):  
Predictive Model ◽  
Conditional Entropy ◽  
Linguistic Complexity ◽  
Trade Off ◽  
Empirical Trade ◽  
Word Forms ◽  
Inflectional Paradigms ◽  
Surface Realization

We quantify the linguistic complexity of different languages’ morphological systems. We verify that there is a statistically significant empirical trade-off between paradigm size and irregularity: A language’s inflectional paradigms may be either large in size or highly irregular, but never both. We define a new measure of paradigm irregularity based on the conditional entropy of the surface realization of a paradigm— how hard it is to jointly predict all the word forms in a paradigm from the lemma. We estimate irregularity by training a predictive model. Our measurements are taken on large morphological paradigms from 36 typologically diverse languages.

The Economics of Decentralization: A Review of the Literature and the Case of Education Provision*

2002 ◽  
Vol 20 (2) ◽  
pp. 147-164
Author(s):  
Roberta Gatti
Keyword(s):  
Evaluation Studies ◽  
Institutional Arrangements ◽  
Review Of The Literature ◽  
Incentive Mechanisms ◽  
Trade Off ◽  
Local Taxes ◽  
Economic Rationale ◽  
The World ◽  
Pros And Cons

Abstract This paper reviews the economic rationale for and against decentralization with particular attention to the organization and delivery of education. The paper frames the overview within the standard efficiency-equity trade off and highlights the increasingly important role of incentive mechanisms, accountability, and citizens' participation. The discussion then turns to the issues that are specific to decentralizing education, including the pros and cons of financing schools from local taxes, and a taxonomy and description of institutional arrangements around the world. A brief review of evaluation studies of decentralization reforms in education concludes the paper.

Is human cognition adaptive?

1991 ◽  
Vol 14 (3) ◽  
pp. 471-485 ◽  
Author(s):  
John R. Anderson
Keyword(s):  
Problem Solving ◽  
Memory Performance ◽  
Human Cognition ◽  
Rational Analysis ◽  
Trade Off ◽  
Hypothesis Formation ◽  
Expected Gain ◽  
The World ◽  
The Difference ◽  
The Cost

AbstractCan the output of human cognition be predicted from the assumption that it is an optimal response to the information-processing demands of the environment? A methodology called rational analysis is described for deriving predictions about cognitive phenomena using optimization assumptions. The predictions flow from the statistical structure of the environment and not the assumed structure of the mind. Bayesian inference is used, assuming that people start with a weak prior model of the world which they integrate with experience to develop stronger models of specific aspects of the world. Cognitive performance maximizes the difference between the expected gain and cost of mental effort. (1) Memory performance can be predicted on the assumption that retrieval seeks a maximal trade-off between the probability of finding the relevant memories and the effort required to do so; in (2) categorization performance there is a similar trade-off between accuracy in predicting object features and the cost of hypothesis formation; in (3) casual inference the trade-off is between accuracy in predicting future events and the cost of hypothesis formation; and in (4) problem solving it is between the probability of achieving goals and the cost of both external and mental problem-solving search. The implemention of these rational prescriptions in neurally plausible architecture is also discussed.

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