57,334 research outputs found
Pseudo-Deterministic Streaming
A pseudo-deterministic algorithm is a (randomized) algorithm which, when run multiple times on the same input, with high probability outputs the same result on all executions. Classic streaming algorithms, such as those for finding heavy hitters, approximate counting, ?_2 approximation, finding a nonzero entry in a vector (for turnstile algorithms) are not pseudo-deterministic. For example, in the instance of finding a nonzero entry in a vector, for any known low-space algorithm A, there exists a stream x so that running A twice on x (using different randomness) would with high probability result in two different entries as the output.
In this work, we study whether it is inherent that these algorithms output different values on different executions. That is, we ask whether these problems have low-memory pseudo-deterministic algorithms. For instance, we show that there is no low-memory pseudo-deterministic algorithm for finding a nonzero entry in a vector (given in a turnstile fashion), and also that there is no low-dimensional pseudo-deterministic sketching algorithm for ?_2 norm estimation. We also exhibit problems which do have low memory pseudo-deterministic algorithms but no low memory deterministic algorithm, such as outputting a nonzero row of a matrix, or outputting a basis for the row-span of a matrix.
We also investigate multi-pseudo-deterministic algorithms: algorithms which with high probability output one of a few options. We show the first lower bounds for such algorithms. This implies that there are streaming problems such that every low space algorithm for the problem must have inputs where there are many valid outputs, all with a significant probability of being outputted
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Autonomic nervous system functioning assessed during the Still-Face Paradigm: A meta-analysis and systematic review of methods, approach and findings.
Animal and human research suggests that the development of the autonomic nervous system (ANS) is particularly sensitive to early parenting experiences. The Still-Face Paradigm (SFP), one of the most widely used measures to assess infant reactivity and emotional competence, evokes infant self-regulatory responses to parental interaction and disengagement. This systematic review of 33 peer-reviewed studies identifies patterns of parasympathetic (PNS) and sympathetic (SNS) nervous system activity demonstrated by infants under one year of age during the SFP and describes findings within the context of sample demographic characteristics, study methodologies, and analyses conducted. A meta-analysis of a subset of 14 studies with sufficient available respiratory sinus arrhythmia (RSA) data examined whether the SFP reliably elicited PNS withdrawal (RSA decrease) during parental disengagement or PNS recovery (RSA increase) during reunion, and whether results differed by socioeconomic status (SES). Across SES, the meta-analysis confirmed that RSA decreased during the still-face episode and increased during reunion. When studies were stratified by SES, low-SES or high-risk groups also showed RSA decreases during the still face episode but failed to show an increase in RSA during reunion. Few studies have examined SNS activity during the SFP to date, preventing conclusions in that domain. The review also identified multiple qualifications to patterns of SFP ANS findings, including those that differed by ethnicity, infant sex, parental sensitivity, and genetics. Strengths and weaknesses in the extant research that may explain some of the variation in findings across the literature are also discussed, and suggestions for strengthening future research are provided
The Number of Firms and the Politics of Export Subsidy
The purpose of this paper is to present a framework to understand that the government's implementation of export subsidy is influenced by the political pressure from the home firms which can bear the costs of forming and maintaining a lobby in order to overcome a free-rider problem associated with lobbying. When the number of the foreign firms is large in comparison with that of the home firms, the home firms can organize a lobby group more easily and lobby for higher export subsidy. The implementation of politically optimal export subsidy can make the domestic social welfare far worse than when the free trade is maintained by a multilateral agreement which prohibit export subsidies.Lobby formation, Political contribution, Export subsidy, Multilateral agreements
Firm Heterogeneity, Contract Enforcement, and the Industry Dynamics of Offshoring
We develop an endogenous growth model to study the long run consequences of offshoring with firm heterogeneity and incomplete contracts. In so doing, we model offshoring as the geographical fragmentation of a firm’s production chain between a home upstream division and a foreign downstream one. On the positive side, we show that, when contracts are incomplete, the possibility of offshoring has favorable implications for economic growth. Yet, offshoring induced by a higher bargaining power of the upstream division can hamper growth: while there is always a positive correlation between upstream bargaining weight and offshoring activities, there is a non-monotonic relationship between these and growth. Whether offshoring with incomplete contracts also increases consumption depends on firm heterogeneity. On the normative side, we show that, whereas with complete contract efficiency is restored through a subsidy to R&D only, with incomplete contracts a production subsidy to offshored upstream divisions is needed too.Offshoring, Heterogeneous Firms, Incomplete Contracts, Growth, Industry Dynamics
Neutrino Parameters, Abelian Flavor Symmetries, and Charged Lepton Flavor Violation
Neutrino masses and mixings have important implications for models of fermion
masses, and, most directly, for the charged lepton sector. We consider
supersymmetric Abelian flavor models, where neutrino mass parameters are
related to those of charged leptons and sleptons. We show that processes such
as \tau to \mu\gamma, \mu to e\gamma and \mu-e conversion provide interesting
probes. In particular, some existing models are excluded by current bounds,
while many others predict rates within reach of proposed near future
experiments. We also construct models in which the predicted rates for charged
lepton flavor violation are below even the proposed experimental sensitivities,
but argue that such models necessarily involve loss of predictive power.Comment: 27 pages, refs added, published versio
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Medication Abortion: A Sample Protocol for Increasing Access During a Pandemic and Beyond
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Trade Barriers As Bargaining Outcomes
Whether bilateral trade barrier data conform with the Grossman-Helpman (1995) model’s predictions about “trade talks” is examined in this article. A simple form of the prediction from the model is tested. Bilateral US-Japan and US-EU data from the 1990s are employed. The results are the first in the literature.Trade talks equilibrium; Nontariff barriers;
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The use of drug calendars for the diagnosis of cutaneous drug eruptions in the age of electronic medical records
A morbilliform drug eruption is the most common condition leading to a dermatology consultation for a patient in the hospital. Timing is an important diagnostic tool since the onset of a skin rash usually takes place within days-to-weeks of the start of the implicated drug. A comprehensive, thorough, and reliable drug history by the clinician is essential. Therefore, to assist in the task of determining the causative medication of a new skin rash in a hospitalized patient, the creation of a drug calendar is recommended. The development of an electronic version of the drug calendar offers several benefits over the manual version. As the use of electronic medical records continues to become the standard in medicine, the electronic drug calendar will serve as an invaluable tool for the diagnosis of drug hypersensitivity
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