Miracle-dz/UniFAR-FTUs huggingface dataset:
Reproducible Bernoulli Cluster Sampling for Analytics Applications at the Petabyte Scale

We describe a sampling application that supports thirteen analytics data-marts by providing database samples and has been in daily operational use for over two years at one of the world’s top web portals. The main requirement for the application is the need to support ad-hoc aggregate queries against data that spans several years and which cannot be stored in its entirety at the low level needed by data-mining applications. Furthermore, since the query load is highly variable, we cannot choose a stratification of the data so we are led to use uniform sampling. Since the source data cannot be stored at the 100% level, we have materialized our samples as substitutes for the source data. Another driving requirement is that the sampling process preserve the entire record of web activity for chosen users if a chosen user appears in multiple populations (tables) she should appear in all the samples derived from those tables. This reduces variance of aggregate metrics based on joining samples and allows us to do longitudinal studies of the chosen users over long time periods. We use Bernoulli (“coin-flip”) sampling because it uses O(1) space whereas reservoir methods require holding a large in-memory array. However, Bernoulli sampling produces variable-sized samples and slightly wider confidence intervals than Simple Random Sampling. We also use Cluster Sampling since in our data, a user corresponds to a cluster of records, one record per web activity event. Our samples are sub-samples from a larger super-sample, therefore confidence intervals for aggregate metrics based on this scheme requires slight extensions to the theory of HorvitzThompson estimators, usually used for confidence intervals for count and sum statistics. We develop this new theory and provide some validation. This new theory complements the application which is used daily by business users to make important business decisions.
The Intractability of Computing the Hamming Distance Universitt at Zu L Ubeck the Intractability of Computing the Hamming Distance

Given a language L, the Hamming distance of a string x to L is the minimum Hamming distance of x to any string in L. The edit distance of a string to a given language is deened similarly. First, we prove that the Hamming distance to languages in AC 0 is hard to approximate; it cannot be approximated within a factor O ? n 1 3 ? , for any > 0, unless P = NP (n denotes the length of the input string). Second, we show the parameterised intractability of computing the Ham-ming distance. We prove that for every t 2 N there exists a language in AC 0 such that the problem of computing the Hamming distance is W t-hard. Moreover , there is a language in P such that computing the Hamming distance to it is W P-hard. Furthermore, we show that the problems of computing the Hamming distance and of computing the edit distance are in some sense equivalent by presenting reductions from the former to the latter problem and vice versa.
The island model as a Markov dynamic system

Parallel multi-deme genetic algorithms are especially advantageous because they allow reducing the time of computations and can perform a much broader search than single-population ones. However, their formal analysis does not seem to have been studied exhaustively enough. In this paper we propose a mathematical framework describing a wide class of island-like strategies as a stationary Markov chain. Our approach uses extensively the modeling principles introduced by Vose, Rudolph and their collaborators. An original and crucial feature of the framework we propose is the mechanism of inter-deme agent operation synchronization. It is important from both a practical and a theoretical point of view. We show that under a mild assumption the resulting Markov chain is ergodic and the sequence of the related sampling measures converges to some invariant measure. The asymptotic guarantee of success is also obtained as a simple issue of ergodicity. Moreover, if the cardinality of each island population grows to infinity, then the sequence of the limit invariant measures contains a weakly convergent subsequence. The formal description of the island model obtained for the case of solving a single-objective problem can also be extended to the multi-objective case
Integrity of the Anterior Visual Pathway and Its Association with Ambulatory Performance in Multiple Sclerosis

Background. Retinal nerve fiber layer thickness (RNFLT) and total macular volume (TMV) represent markers of neuroaxonal degeneration within the anterior visual pathway that might correlate with ambulation in persons with multiple sclerosis (MS). Objective. This study examined the associations between RNFLT and TMV with ambulatory parameters in MS. Methods. Fifty-eight MS patients underwent a neurological examination for generation of an expanded disability status scale (EDSS) score and measurement of RNFLT and TMV using optical coherence tomography (OCT). Participants completed the 6-minute walk (6MW) and the timed 25-foot walk (T25FW). The associations were examined using generalized estimating equation models that accounted for within-patient, inter-eye correlations, and controlled for disease duration, EDSS score, and age. Results. RNFLT was not significantly associated with 6MW (P = 0.99) or T25FW (P = 0.57). TMV was significantly associated with 6MW (P = 0.023) and T25FW (P = 0.005). The coefficients indicated that unit differences in 6MW (100 feet) and T25FW (1 second) were associated with 0.040 and −0.048 unit differences in TMV (mm3), respectively. Conclusion. Integrity of the anterior visual pathway, particularly TMV, might represent a noninvasive measure of neuroaxonal degeneration that is correlated with ambulatory function in MS.
Quote Revisions and The Quoted Size: An Empirical Analysis

We examine the importance of the size quoted by the specialist in the adjustment of prices. The quoted size is the maximum trade size for which the posted quotes are guaranteed. We find that the impact of trades on subsequent quote revisions depends significantly on whether the trade size exceeds the quoted size. Although larger trades are followed by larger quote revisions, most of the variation in quote revisions is explained by whether the trade size exceeds the quoted size. Once it does, further increases in the trade size have no effect. Our results also indicate that only a fraction of trades move the quotes.
On the Distributions of the Lengths of the Longest Increasing and Decreasing Subsequences in Random Words

We consider the distributions of the lengths of the longest weakly increasing and strongly decreasing subsequences in words of length N from an alphabet of k letters. (In the limit as k → ∞ these become the corresponding distributions for permutations on N letters.) We find Toeplitz determinant representations for the exponential generating functions (on N) of these distribution functions and show that they are expressible in terms of solutions of Painlevé V equations. We show further that in the weakly increasing case the generating function gives the distribution of the smallest eigenvalue in the k × k Laguerre random matrix ensemble and that the distribution itself has, after centering and normalizing, an N → ∞ limit which is equal to the distribution function for the largest eigenvalue in the k × k Gaussian Unitary Ensemble.
Neuron-Specific Prolyl-4-Hydroxylase Domain 2 Knockout Reduces Brain Injury After Transient Cerebral Ischemia

Background and Purpose— Numerous factors involved in the adaptive response to hypoxia, including erythropoietin and vascular endothelial growth factor are transcriptionally regulated by hypoxia-inducible factors (HIFs). During normoxia, prolyl-4-hydroxylase domain (PHD) proteins hydroxylate HIF-&agr; subunits, resulting in their degradation. We investigated the effect of neuronal deletion of PHD2, the most abundant isoform in brain, for stroke outcome. Methods— We generated neuron-specific Phd2 knockout mice and subjected animals to systemic hypoxia or transient middle cerebral artery occlusion. Infarct volume and cell death were determined by histology. HIF-1&agr;, HIF-2&agr;, and HIF target genes were analyzed by immunoblotting and real-time polymerase chain reaction, respectively. Results— Neuron-specific ablation of Phd2 significantly increased protein stability of HIF-1&agr; and HIF-2&agr; in the forebrain and enhanced expression of the neuroprotective HIF target genes erythropoietin and vascular endothelial growth factor as well as glucose transporter and glycolysis-related enzymes under hypoxic and ischemic conditions. Mice with Phd2-deficient neurons subjected to transient cerebral ischemia exhibited a strong reduction in infarct size, and cell death of hippocampal CA1 neurons located in the peri-infarct region was dramatically reduced in these mice. Vessel density in forebrain subregions, except for caudate–putamen, was not altered in Phd2-deficient animals. Conclusions— Our findings denote that the endogenous adaptive response on hypoxic–ischemic insults in the brain is at least partly dependent on the activity of HIFs and identify PHD2 as the key regulator for the protective hypoxia response. The results suggest that specific inhibition of PHD2 may provide a useful therapeutic strategy to protect brain tissue from ischemic injury.
Trends, problems and solutions of recommender system

In this era of web, we have a huge amount of information overloaded over Internet. It becomes a herculean task for the user to get the relevant information. To some extent, the problem is being solved by the search engines, but they do not provide the personalization of data. So, to further filter the information, we need a recommendation engine. In this paper, we have described the various web recommender systems in use by some popular web sites on the internet like Amazon.com, LinkedIn.com, and YouTube.com etc. Further, we have described the various approaches used in the various recommender systems such as Content based, Collaborative and Hybrid recommender system. At the end of this paper, we focus on some of the main challenges faced by the web recommender systems and analyze some techniques to overcome them.
Inkomst och ojämlikhet i Sverige 1951-2002

This report reports result about income distribution and mean income for the adult population (aged 20 and over) in Sweden during the period 1951-2002. All results refer to individual income before tax. It also explains how the dataset was produced. In the adult population, income distribution becomes slightly more equal during the 1950’s and the 1960’s. Income inequality fell dramatically in the 1970’s, but changed very little during the 1980’s. In the 1990’s income dispersion increased. Dividing the population by gender, the data shows that while income inequality was relatively stable for men during the 1950’s and 1960’s, it was reduced among women. During the 1970’s, income inequality decreased for both women and men, but more for women than for men. In the 1990’s income inequality increased, more for men than for women. Average income increased steadily until the mid 1970’s, when mean income began to oscillate, increasing in times of economic upturn and decreasing in recessions.
Provably Learning Mixtures of Gaussians and More

Given a random sample, how can one accurately estimate the parameters of the probabilistic model that generated the data? This is a fundamental question in statistical inference and, more recently, in machine learning. One of the most widely studied instances of this problem is estimating the parameters of a mixture of Gaussians, since doing so is of fundamental importance in a wide range of subjects, from physics to social science. The classic, and most popular approach, for learning Gaussian mixture models (GMMs) is the EM algorithm [Dempster et al., 1977]. The EM algorithm is a search heuristic over the parameters that finds a local maximum of the likelihood function, and therefore makes no guarantees that it will converge to an estimate that is close to the true parameters. Furthermore, in practice it has been found to converge very slowly.
A Short-run Demand Flexibility System for U.S. Agricultural Commodities

Using five monthly revisions to USDA crop forecasts (Jul, Aug, Sep, Oct, & Nov), we estimate own‐ and cross‐commodity short‐run demand flexibilities for six domestic agricultural commodities. Our findings indicate that the corn supply influences the expected harvest‐time price of virtually every other major field crop. Moreover, as the share of the corn crop devoted to ethanol production grows, corn and soybean prices become more flexible, while the reverse it true for wheat and oats.
A Genome Wide Association Study for Longevity in Cattle

Longevity is regarded as the most important functional trait in cattle breeding with high economic value yet low heritability. In order to identify genomic regions associated with longevity, a genome wise association study was performed using data from 4887 Fleckvieh bulls and 33,556 SNPs after quality control. Single SNP regression was used for identification of important SNPs including eigenvectors as a means of correction for population structure. SNPs selected with a false discovery rate threshold of 0.05 and with local false discovery rate identified genomic regions associated with longevity which were subsequently cross checked with the National Center for Biotechnology Information (NCBI) database. This, to identify interesting genes in cattle and their homologue forms in other species. The most notable genes were SYT10 located on chromosome 5, ADAMTS3 on chromosome 6, NTRK2 on chromosome 8 and SNTG1 on chromosome 14 of the cattle genome. Several of the genes found have previously been associated with cattle fertility. Poor fertility is an important culling reason and thereby affects longevity in cattle. Several signals were located in regions sparse with described genes, which suggest that there might be several other non-identified genetic pathways for this important trait.
Enhanced Methods for Local Ancestry Assignment in Sequenced Admixed Individuals

Inferring the ancestry at each locus in the genome of recently admixed individuals (e.g., Latino Americans) plays a major role in medical and population genetic inferences, ranging from finding disease-risk loci, to inferring recombination rates, to mapping missing contigs in the human genome. Although many methods for local ancestry inference have been proposed, most are designed for use with genotyping arrays and fail to make use of the full spectrum of data available from sequencing. In addition, current haplotype-based approaches are very computationally demanding, requiring large computational time for moderately large sample sizes. Here we present new methods for local ancestry inference that leverage continent-specific variants (CSVs) to attain increased performance over existing approaches in sequenced admixed genomes. A key feature of our approach is that it incorporates the admixed genomes themselves jointly with public datasets, such as 1000 Genomes, to improve the accuracy of CSV calling. We use simulations to show that our approach attains accuracy similar to widely used computationally intensive haplotype-based approaches with large decreases in runtime. Most importantly, we show that our method recovers comparable local ancestries, as the 1000 Genomes consensus local ancestry calls in the real admixed individuals from the 1000 Genomes Project. We extend our approach to account for low-coverage sequencing and show that accurate local ancestry inference can be attained at low sequencing coverage. Finally, we generalize CSVs to sub-continental population-specific variants (sCSVs) and show that in some cases it is possible to determine the sub-continental ancestry for short chromosomal segments on the basis of sCSVs.
Study of an instability of the PEP-II positron beam (Ohmi effect and multipactoring)

The paper is organized in the following way. First, Ohmi effect induced by direct flow of primary photoelectrons is studied for the PEP-II parameters. The production rate and kinematics take into account the antechamber of the LER. We discuss the effect of the secondary emission of electrons in the AL chamber, where the yield is larger than one. Resonance multipactoring is considered, and then the average density of the secondary electrons is estimated taking into account the space-charge effect and the interaction with the beam. We show that in the extreme case there is a self-consistent regime similar to the regime of the space-charge dominated cathode. Finally, the rate of ion production by accumulated electrons and the possibility of the ion induced pressure instability is discussed.
Speech Intelligibility Prediction Based on Mutual Information

This paper deals with the problem of predicting the average intelligibility of noisy and potentially processed speech signals, as observed by a group of normal hearing listeners. We propose a model which performs this prediction based on the hypothesis that intelligibility is monotonically related to the mutual information between critical-band amplitude envelopes of the clean signal and the corresponding noisy/processed signal. The resulting intelligibility predictor turns out to be a simple function of the mean-square error (mse) that arises when estimating a clean critical-band amplitude using a minimum mean-square error (mmse) estimator based on the noisy/processed amplitude. The proposed model predicts that speech intelligibility cannot be improved by any processing of noisy critical-band amplitudes. Furthermore, the proposed intelligibility predictor performs well ( ρ > 0.95) in predicting the intelligibility of speech signals contaminated by additive noise and potentially non-linearly processed using time-frequency weighting.
Homeownership and ill-being

Social policy aims to relieve the ill-being of low income groups, and housing policies in many European countries promote homeownership for low-income households. Previous economic research on subjective well-being seems to indicate that homeownership increases subjective well-being, but little research is done on the relations between homeownership and ill-being. The present study tries to fill some of this gap by use of panel data from three Danish surveys on living conditions in the years 1976, 1986 and 2000.
Improvising Musical Structure with Hierarchical Neural Nets

Neural networks and recurrent neural networks have been employed to learn, generalize, and generate musical examples and pieces. Yet, these models typically suffer from an inability to characterize and reproduce the long-term dependencies of musical structure, resulting in products that seem to wander aimlessly. We describe and examine three novel hierarchical models that explicitly operate on multiple structural levels. A three layer model is presented, then a weighting policy is added with two different methods of control attempting to maximize global network learning. While the results do not have sufficient structure beyond the phrase or section level, they do evince autonomous generation of recognizable medium-level structures.
Platelet-derived Growth Factor-induced Alterations Vinculin and Actin Distribution in Balb/c-3t3 Cells

Exposure of BALB/c-3T3 cells (clone A31) to platelet-derived growth factor (PDGF) results in a rapid time-and dose-dependent alteration in the distribution of vinculin and actin. PDGF treatment (6-50 ng/ml) causes vinculin to disappear from adhesion plaques (within 2.5 min after PDGF exposure) and is followed by an accumulation of vinculin in punctate spots in the perinuclear region of the cell. This alteration in vinculin distribution is followed by a disruption of actin-containing stress fibers (within 5 to 10 min after PDGF exposure). Vinculin reappears in adhesion plaques by 60 min after PDGF addition while stress fiber staining is nondetectable at this time. PDGF treatment had no effect on talin, vimentin, or microtubule distribution in BALB/c-3T3 cells; in addition, exposure of cells to 5% platelet-poor plasma (PPP), 0.1% PPP, 30 ng/ml epidermal growth factor (EGF), 30 ng/ml somatomedin C, or 10 ~tM insulin also had no effect on vinculin or actin distribution. Other competence-inducing factors (fibroblast growth factor, calcium phosphate, and choleragen) and tumor growth factor produced similar alterations in vinculin and actin distribution as did PDGF, though not to the same extent. PDGF treatment of cells for 60 min followed by exposure to EGF (0.1-30 ng/ml for as long as 8 h after PDGF removal), or 5% PPP resulted in the nontransient disappearance of vinculin staining within 10 min after EGF or PPP additions; PDGF followed by 0.1% PPP or 10/zM insulin had no effect. Treatment of cells with low doses of PDGF (3.25 ng/ml), which did not affect vinculin or actin organization in cells, followed by EGF (10 ng/ml), resulted in the disappearance of vinculin staining in adhesion plaques, thus demonstrating the synergistic nature of PDGF and EGF. These data suggest that PDGF-induced competence and stimulation of cell growth in quiescent fibroblasts are associated with specific rapid alterations in the cellular organization of vinculin and actin. Platelet-derived growth factor (PDGF) ~ is the major mitogenic growth factor in serum for cells of mesenchymal origin (2, 44), in addition to being a major chemoattractant for human neutrophils and monocytes (13), fibroblasts (45, 49), and smooth muscle cell~ (50), thereby potentially playing an important role in wound healing, atherogenesis, and cell growth. The biochemical mechanisms by which PDGF regulates the growth of cells is not known. Recent work has shown that PDGF and growth factors in platelet-poor plasma (PPP) func-Abbreviations used in this paper. tion in a synergistic manner to control …
Conflict and consensus in social policy development

Abstract. In the study of welfare state development, we find divergent approaches which assign differing weights to consensus and conflict as well as to various causal factors behind changes in social policy. This paper moves beyond the traditional concentration on social expenditures and tests the role of different causal factors by focussing instead on the development of social rights in the areas of workplace accidents, sickness, and unemployment insurance. Hypotheses derived from competing approaches are tested in relation to the relative development of social rights in these three policy areas and in relation to variation in social rights in accident insurance.
A correlation based face verification scheme designed for mobile device access control: From algorithm to Java ME implementation

In this paper, we investigate face recognition based access control approaches dedicatedly designed for camera-equipped mobile devices. We developed a Hierarchical Correlation based Face Verification (HCFV) scheme which is deployable for the most resource constrained mobile devices such as low-end mobile phones with available memory size less than 1MB. The novelty of HCFV is to perform the Partial Correlation Output Peak Analysis (analyze the relations among multiple cross-correlation peaks which are generated from selected sub-regions of a face). The experimental results on the public domain database Yale Face Database demonstrate that the proposed scheme has achieved better performance than using conventional correlation based schemes directly on either full-size or downsized images. Furthermore, in order to investigate the applicability and implementability issues, we have also implemented HCFV on the Nokia S60 CLDC emulator using Java ME programming technology. The experiment shows that HFVC consumes approximately 1/10 memory, 1/6 storage space, and 3.5% processing time in comparison with the result using the conventional correlation methods.