Clear Intuition Research Articles

Optimal estimation of pure states with displaced-null measurements

We revisit the problem of estimating an unknown parameter of a pure quantum state, and investigate ‘null-measurement’ strategies in which the experimenter aims to measure in a basis that contains a vector close to the true system state. Such strategies are known to approach the quantum Fisher information for models where the quantum Cramér-Rao bound (QCRB) is achievable but a detailed adaptive strategy for achieving the bound in the multi-copy setting has been lacking. We first show that the following naive null-measurement implementation fails to attain even the standard estimation scaling: estimate the parameter on a small sub-sample, and apply the null-measurement corresponding to the estimated value on the rest of the systems. This is due to non-identifiability issues specific to null-measurements, which arise when the true and reference parameters are close to each other. To avoid this, we propose the alternative displaced-null measurement strategy in which the reference parameter is altered by a small amount which is sufficient to ensure parameter identifiability. We use this strategy to devise asymptotically optimal measurements for models where the QCRB is achievable. More generally, we extend the method to arbitrary multi-parameter models and prove the asymptotic achievability of the the Holevo bound. An important tool in our analysis is the theory of quantum local asymptotic normality which provides a clear intuition about the design of the proposed estimators, and shows that they have asymptotically normal distributions.

Formula omitted]R loss: A weighted loss by multiplicative factors using sigmoidal functions

In neural networks, the loss function represents the core of the learning process that leads the optimizer to an approximation of the optimal convergence error. Convolutional neural networks (CNN) use the loss function as a supervisory signal to train a deep model and contribute significantly to achieving the state of the art in some fields of artificial vision. Cross-entropy (CE) and Center loss (CL) functions are commonly used to increase the discriminating power of learned functions and increase the generalization performance of the model. Center loss minimizes the class intra-class variance and at the same time penalizes the long distance between the deep features inside each class. However, the total error of the center loss will be heavily influenced by the majority of the instances and can lead to a freezing state in terms of intra-class variance. To address this, we introduce a new loss function called sigma squared reduction loss (σ2R loss), which is regulated by a sigmoid function to inflate/deflate the error per instance and then continue to reduce the intra-class variance. Our loss has clear intuition and geometric interpretation, furthermore, we demonstrate by experiments the effectiveness of our proposal on several benchmark datasets showing the intra-class variance reduction and overcoming the results obtained with center loss and soft nearest neighbour functions.

The dynamics and elasticities on the U.S. natural gas market. A Bayesian Structural VAR analysis

Natural gas is an important source of energy in the global economy, hence understanding the drivers of its prices is of significant interest for economic agents. This paper investigates the role of structural shocks for the dynamics of the U.S. natural gas market within the Bayesian Structural Vector Autoregression framework applied by Baumeister and Hamilton (2019a, AER), to the crude oil market. This approach provides clear intuition for the identification strategy and allows us to correctly estimate the short-term price elasticity of natural gas supply and demand. Our results indicate that the former is low, whereas the latter is higher than the average estimate in the literature. We also show that market specific demand shocks explain a dominant fraction of natural gas prices variability, while the contribution of supply, aggregate economic activity and inventory shocks is important only during specific market events such as the recent outbreak of the COVID-19 pandemic. Finally, we illustrate how changes in supply in the era of shale gas revolution contributed to the dynamics of natural gas prices.

Anti-crossings and spectral gap during quantum adiabatic evolution

We aim to give more insights on adiabatic evolution concerning the occurrence of anti-crossings and their link to the spectral minimum gap $\Delta_{min}$. We study in detail adiabatic quantum computation applied to a specific combinatorial problem called weighted max $k$-clique. A clear intuition of the parametrization introduced by V. Choi is given which explains why the characterization isn't general enough. We show that the instantaneous vectors involved in the anti-crossing vary brutally through it making the instantaneous ground-state hard to follow during the evolution. This result leads to a relaxation of the parametrization to be more general.

Young Children’s Judgments of Counter-Intuitive Information and Its Relation with Executive Function

Objectives: This study examined young children’s judgments of counter-intuitive information, and whether their judgments relate to the executive function and theory of mind.Methods: Ninety-two children aged 3 to 6 years were provided with counter-intuitive information that the smallest doll was the heaviest among five Russian dolls in a one-on-one interview with a researcher. Subsequently, how children judged the weights of the dolls, whether they did an experiment to check the weights during the researcher’s absence, how they judged the weights upon the researcher’s suggestion, and whether their judgments were related to the executive function and theory of mind were examined.Results: Following the researcher’s counter-intuitive information, the 3-year-olds were more likely to judge that the smallest one might be the heaviest. Further, spontaneous experiments during the researcher’s absence were conducted only among a small number of children aged 4-years and up. There were no more differences in judgments of weight among age groups of children when it came to checking the actual weights of the dolls upon the researcher’s suggestion. Additionally, children with better inhibitory and shifting ability tended to judge the heaviest doll based on their own intuition. A multiple regression analysis, controlling for relevant variables showed that only shifting ability predicted the children’s judgments based on their intuition before the suggested experiment.Conclusion: With age, young children may come to judge a physical situation based on their own clear intuition, rather than merely following another’s counter-intuitive information. This tendency appears to be related to the executive function, especially shifting ability.

Spire: A Cooperative, Phase-Symmetric Solution to Distributed Consensus

All existing solutions to distributed consensus are organised around a Paxos-like structure wherein processes contend for exclusive leadership in one phase, and then either use their dominant position to propose a value in the next phase or elect an alternate leader. This approach may be characterised as adversarial and phase-asymmetric, requiring distinct message schemas and process behaviours for each phase. In over three decades of research, no algorithm has diverged from this basic model, alluding to it perhaps being the only viable solution to consensus. This paper presents a new consensus algorithm named Spire, characterised by a phase-symmetric, cooperative structure. Processes do not contend for leadership; instead, they collude to iteratively establish a dominant value and may do so concurrently without conflicting. Each successive iteration is structured identically to the previous, employing the same messages and invoking the same behaviour. By these characteristics, Spire buckles the trend in protocol design, proving that at least two disjoint cardinal solutions to consensus exist. The resulting phase symmetry halves the number of distinct messages and behaviours, offering a clear intuition and an approachable foundation for learning consensus and building practical systems.

Extensions of Brownian motion to a family of Grushin-type singularities

We consider a one-parameter family of Grushin-type singularities on surfaces, and discuss the possible diffusions that extend Brownian motion to the singularity. This gives a quick proof and clear intuition for the fact that heat can only cross the singularity for an intermediate range of the parameter. When crossing is possible and the singularity consists of one point, we give a complete description of these diffusions, and we describe a “best” extension, which respects the isometry group of the surface and also realizes the unique symmetric one-point extension of the Brownian motion, in the sense of Chen-Fukushima. This extension, however, does not correspond to the bridging extension, which was introduced by Boscain-Prandi, when they previously considered self-adjoint extensions of the Laplace-Beltrami operator on the Riemannian part for these surfaces. We clarify that several of the extensions they considered induce diffusions that are carried by the Martin compactification at the singularity, which is much larger than the (one-point) metric completion. In the case when the singularity is more than one-point, a complete classification of diffusions extending Brownian motion would be unwieldy. Nonetheless, we again describe a “best” extension which respects the isometry group, and in this case, this diffusion corresponds to the bridging extension. A prominent role is played by Bessel processes (of every real dimension) and the classical theory of one-dimensional diffusions and their boundary conditions.

Licensing of a Korean Honorific si and Its Scalarity

In the standard Korean subject honorification, an honorific si honors a human surface subject. However, the existence of si, which is now being interpreted to honor a nonhuman subject, has been causing controversy in recent years. Quite a few Korean linguists analyze this as a strategic usage and call it the hearer honorification, which is to honor the hearer, not the subject, whereas the National Institute of Korean Language and the media define it as a serious misuse. In this situation, based on the results of a survey on the nonhuman surface subject honorification (NSSH), we have proposed that a clear intuition on the contrast between proper and improper uses of NSSH is maintained (Yoon 2017). Given this, one purpose of this paper is to investigate various ways of proper indirect licensing of si in NSSH based on experimental results that confirm the validity of the proposed rules of indirect licensing of si by both older and younger generations. More importantly, another purpose is to demonstrate the scalarity of indirect licensing of si, which will be proposed to be the main cause of the current and slightly confusing situation regarding the use of si.

Back to Bargaining Basics: A Simple 50-50 Model for Splitting a Pie

Nash (1950) and Rubinstein (1982) give two different justifications for a 50-50 split of surplus to be the outcome of bargaining with two players. Nash's axioms extend to n players, but the search for a satisfactory n-player non-cooperative game theory model of bargaining has been fruitless. I offer a simple static model that reaches a 50-50 split (or 1/n) as the unique equilibrium. Each player chooses a level simultaneously, but greater toughness always generates a risk of breakdown. Introducing asymmetry, a player who is more risk averse gets a smaller share in equilibrium. Bargaining strength can also be parameterized to yield an asymmetric split. The model can be expanded to resemble Rubinstein (1982) by making breakdown mere delay, but with an exact 50-50 split if the player's discount rates are equal. The model only needs minimal assumptions on breakdown probability and pie division as functions of toughness and has a clear intuition: whoever has a bigger share loses more from breakdown and hence has less incentive to be tough.

A Novel Interpretation for Opinion Consensus in Social Networks With Antagonisms

We take a new perspective for the consensus in DeGroot-type social networks with antagonistic interactions between some pairs of agents. We observe the analogies between social networks and electrical networks. A line with positive (or negative) conductance in the electrical network well corresponds to the cooperative (or antagonistic) interaction in the social network. Then, we introduce a refined definition of effective conductance (EC), which comes from electrical networks, into social networks as a characterization of the overall relationship between a pair of agents. The EC considers the effects of both direct and indirect interactions between the agents. Some EC-based consensus criteria are established by analytical and statistical approaches, showing that the sign of EC is a useful indicator of consensus. The opinion consensus can be generally interpreted as every pair of agents being overall cooperative despite antagonistic interactions, i.e., the corresponding EC being positive. The obtained results provide new insights into the consensus mechanism with clear intuition. Case study of a 15-agent network is provided as an illustration.

Bayesian Model Averaging With Exponentiated Least Squares Loss

The model averaging problem is to average multiple models to achieve a prediction accuracy not much worse than that of the best single model in terms of mean-squared error. It is known that if the models are misspecified, model averaging is superior to model selection. Specifically, let $n$ be the sample size, then the worst case regret of the former decays at a rate of $O(1/n)$ , whereas the worst case regret of the latter decays at a rate of $O(1/\sqrt {n})$ . The recently proposed $Q$ -aggregation algorithm solves the model averaging problem with the optimal regret of $O(1/n)$ both in expectation and in deviation; however, it suffers from two limitations: 1) for continuous dictionary, the proposed greedy algorithm for solving $Q$ -aggregation is not applicable and 2) the formulation of $Q$ -aggregation appears ad hoc without clear intuition. This paper examines a different approach to model averaging by considering a Bayes estimator for deviation optimal model averaging by using exponentiated least squares loss. We establish a primal-dual relationship of this estimator and that of $Q$ -aggregation and propose new algorithms that satisfactorily resolve the above-mentioned limitations of $Q$ -aggregation.

Physical approach to quantum networks with massive particles

This paper treats a quantum network from a physical approach, explicitly finds the physical eigenstates and compares them to the quantum-graph description. The basic building block of a quantum network is an X-shaped potential well made by crossing two quantum wires, and we consider a massive particle in such an X well. The system is analyzed using a variational method based on an expansion into modes with fast convergence and it provides a very clear intuition for the physics of the problem. The particle is found to have a ground state that is exponentially localized to the center of the X well, and the other symmetric solutions are formed so to be orthogonal to the ground state. This is in contrast to the predictions of the conventionally used so-called Kirchoff boundary conditions in quantum graph theory that predict a different sequence of symmetric solutions that cannot be physically realized. Numerical methods have previously been the only source of information on the ground-state wave function and our results provide a different perspective with strong analytical insights. The ground-state wave function has the shape of a solitonic solution to the non-linear Schr{\"o}dinger equation, enabling an analytical prediction of the wave number. When combining multiple X wells into a network or grid, each site supports a solitonic localized state. The solitons only couple to each other and are able to jump from one site to another as if they were trapped in a discrete lattice.

Korean Honorific si and Its Licensing

Korean is known to have a well-developed honorification system, which is observed to be composed of strategic as well as normative honorification rules. Given this, how to treat the so-called hearer honorific si, which is to honor the hearer, not to honor the subject NP predicated with the verb with si, has been a quite controversial issue in recent years. National Institute of Korean Language and the media are labeling this usage, which is mostly observed in the service context, as a serious language misuse. In contrast, quite a few Korean linguists analyze it as a strategic usage extended from the Korean honorification system. In this context, the purpose of this paper is to reinvestigate whether it is a legitimate usage or an overuse of honorifics. The results of a survey that has been conducted to provide an answer to the issue shows that this is a quite complicated phenomenon, but that Korean language users seem to maintain a quite clear intuition on the distinction between appropriate and inappropriate uses of honorification. It will be proposed that the licensing of si is scalar, which should be accounted for by the direct link between the predication with si and a human NP.

Tribute to Omri Ben-Shahar

Previous articleNext article FreeTribute to Omri Ben-ShaharWilliam H. J. Hubbard and Edward R. MorrisonWilliam H. J. Hubbard Search for more articles by this author and Edward R. Morrison Search for more articles by this author PDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreAs of this issue, and after 8 years of service, Omri Ben-Shahar is stepping down as an editor of the Journal of Legal Studies. During our 3 years as his fellow editors, Omri was our wise and indefatigable colleague. He brought to the journal his penetrating insight, always able to identify core insights in submissions and working tirelessly with authors (and his fellow editors) to unearth, clarify, and sharpen the insights. He set an editorial standard to which we aspire.Omri shepherded the JLS through a period of growth. Submissions have steadily risen: during his tenure as editor, the JLS published 165 articles from well over 1,000 individual submissions plus five conferences. And we have witnessed greater methodological diversity and sophistication in submissions. For the JLS, these welcome developments have presented a particular challenge: the increasing sophistication of theoretical and empirical methodologies in social science tends to make interdisciplinary work in law less accessible to broad audiences. In meeting this challenge, Omri firmly maintained an editorial vision that theoretical frameworks and empirical strategies can and should be described with clear intuition and plain language (even if also articulated with formal rigor, of course). Omri brought to the JLS the same emphasis on big ideas, theory-driven insights, and an embrace of empiricism that characterizes his own innovative and influential scholarship.It has been a joy and privilege for us to serve as editors of the JLS with Omri Ben-Shahar. We miss him. Previous articleNext article DetailsFiguresReferencesCited by The Journal of Legal Studies Volume 46, Number 1January 2017 Sponsored by The University of Chicago Law School Article DOIhttps://doi.org/10.1086/692334 © 2017 by The University of Chicago. All rights reservedPDF download Crossref reports no articles citing this article.

‹Der graphematische Satz.›

Abstract The starting point of this paper is the question how the graphematic sentence, i. e. the written sentence, can be defined. The answer seems to be clear: a graphematic sentence begins with a sentence-initial capital letter and is concluded by a sentence-final punctuation mark such as the full stop or the question mark. However, this definition is problematic since it requires an underlying (syntactic) definition of the sentence in general. Yet within linguistics there is no commonly accepted definition of the sentence (cf. section 1). Language users (linguists among them), however, seem to have a clear idea of what a sentence is. In the paper I argue that this seemingly contradictory situation could be explained on the following two assumptions. (a) The widespread clear intuition about the existence of a linguistic category called ‘sentence’ mainly derives from the influence of the written language on concepts of language in general. (b) Yet this influence has never really been taken into consideration for sentence definitions within modern linguistics due to the fact that written language has for long time been neglected as an object of linguistic research (cf. section 2). The main part of the paper (section 3) is concerned with a definition of the graphematic sentence without recourse to syntactic structures. It reveals that in German the graphematic sentence is a clearly recognizable unit within the writing system and therefore seems to be predestined for being the conceptional model for the idea of what a sentence is. Based on the punctuation theory of Bredel (2008, 2011) I argue that punctuation marks do not indicate sentences but rather constitute them. Finally I discuss how the graphematic analysis presented here can constitute the basis for empirical approaches towards a linguistic reconstruction of the widespread idea of what a sentence is (cf. section 4).

Water charging and water saving in agriculture. Insights from a Revealed Preference Model in a Mediterranean basin

The large irrigation expansion of the last 50 years has increased pressure on water resources in EU Mediterranean basins. Water charging has been encouraged, since within the EU policy context it is believed that higher charges reduce water use. This paper presents a Revealed Preference Model that provides a clear intuition of the logic behind farmers' choices using standard economic analysis and implementing a multi-attribute utility function. The model is calibrated for the profitable Agricultural Districts (ADs) in the overexploited Segura River Basin (SRB) in southeastern Spain. Results show that water use is highly inelastic for charge increases below 0.5 €/m3 (i.e. a water charge increase of 600%), and only starts showing a significant reduction for water charges above this threshold. However, water charging can still be used to promote the swap of overused and inexpensive conventional resources by underused and more expensive desalinated water.

Taxation and Saving – A Retrospective

Atkinson and Sandmo (1980) evaluated the taxation of saving by embedding the static optimal-tax framework within the two-period overlapping-generations model. Using this model, they collected a series of important results for optimal taxes on labour and capital income under a variety of assumptions regarding the instruments and objectives of the government, in particular the availability of national debt to spread burdens among different generations of individuals. With clear intuition and presentation, the study remains an important source for understanding the welfare implications of the taxation of saving.

A Dynamic Neighborhood Selection Approach for Locally Linear Embedding

Locally linear embedding is based on the assumption that the whole data manifolds are evenly distributed so that they determine the neighborhood for all points with the same neighborhood size. Accordingly, they fail to nicely deal with most real problems that are unevenly distributed. This paper presents a new approach that takes the general conceptual framework of Hessian locally linear embedding so as to guarantee its correctness in the setting of local isometry to an open connected subset but dynamically determines the local neighborhood size for each point. This approach estimates the approximate geodesic distance between any two points by the shortest path in the local neighborhood graph, and then determines the neighborhood size for each point by using the relationship between its local estimated geodesic distance matrix and local Euclidean distance matrix. This approach has clear geometry intuition as well as the better performance and stability to deal with the sparsely sampled or noise contaminated data sets that are often unevenly distributed. The conducted experiments on benchmark data sets validate the proposed approach.

The Argument from Nominal–Notable Comparisons, ‘Ought All Things Considered’, and Normative Pluralism

The idea that morality and prudence are incommensurable normative domains—a central idea in normative pluralism—tends to be rejected because of the argument from nominal–notable comparisons. The argument relies on a premise that there are situations of moral–prudential conflict where we have a clear intuition that there are things we ought to do “all things considered”. It is usually concluded that this shows that morality and prudence must be comparable. I argue that normative pluralists, who defend this type of incommensurability, can account for these intuitions by (1) arguing that an “ought all things considered” need not presuppose inter-type comparability among the reasons it covers, and (2) by endorsing more sophisticated theories of prudence; theories for which there are good, independent reasons to endorse, in any case. By following these steps, normative pluralism does not need to have the counterintuitive implications it is often thought to have.

Distributed energy-efficient estimation in spatially correlated wireless sensor networks

We study the problem of maximizing lifetime in sensor networks that are deployed for estimating an unknown parameter or process. Sensors take measurements and transport them in multi-hop fashion to a fusion center (FC) for Maximum Likelihood (ML) estimation of this process. A prime distinguishing feature of wireless sensor networks is the spatial correlation among measurements of nearby sensors. We investigate the way spatial correlation shapes the tradeoff between estimation quality and energy efficiency, according to which more measurement data improve estimation quality, but they are more energy-costly to transport. If the effect of spatial correlation is understood, then a given estimation quality can be achieved with minimum data redundancy and energy consumption. We study the dynamic control of the sensor sampling rates and the routes to the FC. Sensor attributes such as spatial correlation, measurement accuracy and energy reserve as well as the quality of wireless links, collectively affect the sampling rates and routes to the FC. Further, due to spatial correlation, sensor sampling rates alter the joint probability density functions (p.d.f’s) for sensor readings and thus they affect the average estimation error. We show that the optimization problem can be decomposed into smaller ones, where each sensor autonomously takes its sampling rate and next-hop forwarding decisions, and we propose an iterative, low-overhead primal–dual algorithm. Our work yields interesting insights on the fundamental tradeoff between network lifetime and estimation quality, it provides a clear intuition on when spatial correlation is beneficial for the tradeoff above, and it provides a solution with distributed sensor coordination.