11,603 research outputs found
Statistical Analysis of fMRI Time-Series: A Critical Review of the GLM Approach.
Functional magnetic resonance imaging (fMRI) is one of the most widely used tools to study the neural underpinnings of human cognition. Standard analysis of fMRI data relies on a general linear model (GLM) approach to separate stimulus induced signals from noise. Crucially, this approach relies on a number of assumptions about the data which, for inferences to be valid, must be met. The current paper reviews the GLM approach to analysis of fMRI time-series, focusing in particular on the degree to which such data abides by the assumptions of the GLM framework, and on the methods that have been developed to correct for any violation of those assumptions. Rather than biasing estimates of effect size, the major consequence of non-conformity to the assumptions is to introduce bias into estimates of the variance, thus affecting test statistics, power, and false positive rates. Furthermore, this bias can have pervasive effects on both individual subject and group-level statistics, potentially yielding qualitatively different results across replications, especially after the thresholding procedures commonly used for inference-making
Openness and Income Dispaities: Does Trade Explain the 'Mezzogiorno' Effect?
Many theoretical models show that trade openness has positive welfare implications. Yet, openness might affect different social groups and regions asymmetrically, even within a given country. We use Italian regional data to answer the question whether trade openness affects within-country income differentials. In Italy, the more affluent regions are internationally more open than poorer ones not only with respect to trade in goods, but also with respect to FDI and international migration. Prima facie, there is a positive correlation between openness and per capita income. Studying this relationship empirically requires taking into account the endogenous component of openness. We apply panel cointegration and instrumental variables techniques to account for the endogeneity of trade. Our results show a positive link between trade openness and the level of income per capita.Openness, growth, regional income disparities, Italian regions
Cell Migration - Methods and Protocols
As the title suggests, this book presents several techniques to study cells migration in vivo, in vitro, ex vivo and with different model systems to dissect many of the biochemical and biophysical properties (at both molecular and cellular levels) involved in the dynamics of migration and cell-to-cell communication..
Trade's Impact on the Labor Share: Evidence from German and Italian Regions
Has the labor share declined? And what is the impact of international trade? These questions are not only relevant in an international context they also matter for understanding the regional distribution of incomes in a given country. In this paper, we study two regions with trade exposures that differ from the rest of the country, and which display distinct changes in the labor share. East German and Southern Italian regions have a degree of international openness which is below the countriesâ averages. At the same time, there has been a more pronounced decline in the labor share in East Germany than in West Germany. In Southern Italy, the labor share has increased in recent years. We show that increased trade openness is not the main culprit behind changing labor shares.labor share, trade, regions
CayleyNets: Graph Convolutional Neural Networks with Complex Rational Spectral Filters
The rise of graph-structured data such as social networks, regulatory
networks, citation graphs, and functional brain networks, in combination with
resounding success of deep learning in various applications, has brought the
interest in generalizing deep learning models to non-Euclidean domains. In this
paper, we introduce a new spectral domain convolutional architecture for deep
learning on graphs. The core ingredient of our model is a new class of
parametric rational complex functions (Cayley polynomials) allowing to
efficiently compute spectral filters on graphs that specialize on frequency
bands of interest. Our model generates rich spectral filters that are localized
in space, scales linearly with the size of the input data for
sparsely-connected graphs, and can handle different constructions of Laplacian
operators. Extensive experimental results show the superior performance of our
approach, in comparison to other spectral domain convolutional architectures,
on spectral image classification, community detection, vertex classification
and matrix completion tasks
Making simple proofs simpler
An open partition \pi{} [Cod09a, Cod09b] of a tree T is a partition of the
vertices of T with the property that, for each block B of \pi, the upset of B
is a union of blocks of \pi. This paper deals with the number, NP(n), of open
partitions of the tree, V_n, made of two chains with n points each, that share
the root
S10-01 Is empathy always good?
Empathy is a complex phenomenon. First of all empathy means the capacity to understand someone else's state of mind or to identify with his emotional state. From this point of view, empathy plays a fundamental role in psychotherapy and has been studied as a fundamental therapeutic factor. It is true that an emphatic attitude can help other people and lead to a better understanding of their feelings. But empathy can also be used as a horrible instrument to manipulate and abuse the other. We can see this kind of malign empathy in perverted narcissistic relationships, in sadism or in torture, where the torturer can use empathy in order to figure out the most effective ways to make each of his victims suffer
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