1,721,307 research outputs found
Imprese innovative, asimmetrie informative e informal venture capital in Italia: alcune evidenze empiriche, Quaderno di ricerca del Dipartimento di Strategie Aziendali della Seconda Università di Napoli
No full textEfecto de las prácticas zootécnicas en lechones lactantes y su impacto en variables productivas, niveles de glucosa y leucograma
Full text linkPósterEl objetivo del trabajo fue determinar el efecto de la edad en la que se realizan las prácticas de manejo del lechón, sobre variables productivas ganancia media diaria (gmd)) y niveles sanguíneos de glucosa, linfocitos y leucocitos.EEA Las BreñasFil: Gonzalez, Maria De Los Angeles. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Las Breñas; ArgentinaFil: Maggioni, M. Actividad privada; Argentin
LOCALIZZAZIONE E AGGLOMERAZIONE PRODUTTIVA: L'ANALISI TERRITORIALE DEI MERCATI DEL LAVORO
No full text
Multiscale regression on unknown manifolds
No full textWe consider the regression problem of estimating functions on RD but supported on a d-dimensional manifold M ⊂ RD with d D. Drawing ideas from multi-resolution analysis and nonlinear approximation, we construct low-dimensional coordinates on M at multiple scales, and perform multiscale regression by local polynomial fitting. We propose a data-driven wavelet thresholding scheme that automatically adapts to the unknown regularity of the function, allowing for efficient estimation of functions exhibiting nonuniform regularity at different locations and scales. We analyze the generalization error of our method by proving finite sample bounds in high probability on rich classes of priors. Our estimator attains optimal learning rates (up to logarithmic factors) as if the function was defined on a known Euclidean domain of dimension d, instead of an unknown manifold embedded in RD. The implemented algorithm has quasilinear complexity in the sample size, with constants linear in D and exponential in d. Our work therefore establishes a new framework for regression on low-dimensional sets embedded in high dimensions, with fast implementation and strong theoretical guarantees
Learning adaptive multiscale approximations to data and functions near low-dimensional sets
No full textIn the setting where a data set in D consists of samples from a probability measure ρ concentrated on or near an unknown d-dimensional set M, with D large but d ≪ D, we consider two sets of problems: geometric approximation of M and regression of a function on M. In the first case we construct multiscale low-dimensional empirical approximations ofM, which are adaptive whenMhas geometric regularity that may vary at different locations and scales, and give performance guarantees. In the second case we exploit these empirical geometric approximations to construct multiscale approximations to on M, which adapt to the unknown regularity of even when this varies at different scales and locations. We prove guarantees showing that we attain the same learning rates as if was defined on a Euclidean domain of dimension d, instead of an unknown manifold M. All algorithms have complexity O(n log n), with constants scaling linearly in D and exponentially in d
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
