Search results for " Max"
showing 10 items of 878 documents
Are Farmers in Alternative Food Networks Social Entrepreneurs? Evidence from a Behavioral Approach
2015
Social entrepreneurship, individual activities with a social objective, is used in this study as a conceptual tool for empirically examining farmers’ participation in alternative food networks (AFNs). This study verifies whether their participation is driven by the social entrepreneurship dimension to satisfy social and environmental needs. We develop a more inclusive view of how social entrepreneurship is present among farmers participating in AFNs by using a behavioural approach based on three main psychological constructs: attitude, objective, and behaviour. The empirical results show that two types of farmers participate in AFNs. One type is closer to commercial entrepreneurs; the main …
Is there sustainable entrepreneurship in the wine industry? Exploring Sicilian wineries participating in the SOStain program
2016
Abstract Global climate change and the accelerating depletion of natural resources have contributed to increase discussions about the role of private enterprises in reversing negative environmental trends. Rather than focusing on profit maximization, policy makers and consumers pressure groups expect firms to meet a triple-bottom line of economic, environmental and social value creation. Hence sustainable entrepreneurship has received recently increasing interest as a phenomenon and a research topic. More recently, the concept of sustainability has been taken seriously in the Italian wine industry. The organizational challenge for entrepreneurship is to better integrate social and environme…
Performance assessment of individual and ensemble data-mining techniques for gully erosion modeling
2017
Gully erosion is identified as an important sediment source in a range of environments and plays a conclusive role in redistribution of eroded soils on a slope. Hence, addressing spatial occurrence pattern of this phenomenon is very important. Different ensemble models and their single counterparts, mostly data mining methods, have been used for gully erosion susceptibility mapping; however, their calibration and validation procedures need to be thoroughly addressed. The current study presents a series of individual and ensemble data mining methods including artificial neural network (ANN), support vector machine (SVM), maximum entropy (ME), ANN-SVM, ANN-ME, and SVM-ME to map gully erosion …
Comparative Analysis of Cell Proliferation Ratio in Oral Lichen Planus, Epithelial Dysplasia and Oral Squamous Cell Carcinoma
2009
Made available in DSpace on 2013-08-12T18:47:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-01 Made available in DSpace on 2013-09-30T18:34:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T14:04:33Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T14:04:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-11-01 Background: Although oral lichen planus has been classified by the World Health Organization (WHO) as a potentially malignant disorder, such classification is still the target of much controversy. Aim: To evaluate the cell proliferation rate in oral lic…
Dysplasia in oral lichen planus: relevance, controversies and challenges. A position paper
2021
Background: Patients with oral lichen planus (OLP) have an increased risk of oral cancer. For this reason, OLP is classified as an oral potentially malignant disorder. However, the precise personal (or individual) risk is unknown. Recent meta-analytical studies have reported that dysplastic OLP may transform to cancer in around 6% of cases, while the rate of transformation is lower (<1.5%) in non-dysplastic cases. The presence of epithelial dysplasia has emerged as the most powerful indicator for assessing cancer risk in oral potentially malignant disorders in routine practice. However, the general acceptance of epithelial dysplasia as an accompanying histologic feature in OLP is subject to…
Estimation of ordered response models with sample selection
2011
We introduce two new Stata commands for the estimation of an ordered response model with sample selection. The opsel command uses a standard maximum-likelihood approach to fit a parametric specification of the model where errors are assumed to follow a bivariate Gaussian distribution. The snpopsel command uses the semi-nonparametric approach of Gallant and Nychka (1987, Econometrica 55: 363–390) to fit a semiparametric specification of the model where the bivariate density function of the errors is approximated by a Hermite polynomial expansion. The snpopsel command extends the set of Stata routines for semi-nonparametric estimation of discrete response models. Compared to the other semi-n…
Right-jumps and pattern avoiding permutations
2015
We study the iteration of the process "a particle jumps to the right" in permutations. We prove that the set of permutations obtained in this model after a given number of iterations from the identity is a class of pattern avoiding permutations. We characterize the elements of the basis of this class and we enumerate these "forbidden minimal patterns" by giving their bivariate exponential generating function: we achieve this via a catalytic variable, the number of left-to-right maxima. We show that this generating function is a D-finite function satisfying a nice differential equation of order~2. We give some congruence properties for the coefficients of this generating function, and we sho…
Whom to befriend to influence people
2020
Alice wants to join a new social network, and influence its members to adopt a new product or idea. Each person $v$ in the network has a certain threshold $t(v)$ for {\em activation}, i.e adoption of the product or idea. If $v$ has at least $t(v)$ activated neighbors, then $v$ will also become activated. If Alice wants to activate the entire social network, whom should she befriend? More generally, we study the problem of finding the minimum number of links that a set of external influencers should form to people in the network, in order to activate the entire social network. This {\em Minimum Links} Problem has applications in viral marketing and the study of epidemics. Its solution can be…
Bayesian inference for the extremal dependence
2016
A simple approach for modeling multivariate extremes is to consider the vector of component-wise maxima and their max-stable distributions. The extremal dependence can be inferred by estimating the angular measure or, alternatively, the Pickands dependence function. We propose a nonparametric Bayesian model that allows, in the bivariate case, the simultaneous estimation of both functional representations through the use of polynomials in the Bernstein form. The constraints required to provide a valid extremal dependence are addressed in a straightforward manner, by placing a prior on the coefficients of the Bernstein polynomials which gives probability one to the set of valid functions. The…
Bootstrap validation of links of a minimum spanning tree
2018
We describe two different bootstrap methods applied to the detection of a minimum spanning tree obtained from a set of multivariate variables. We show that two different bootstrap procedures provide partly distinct information that can be highly informative about the investigated complex system. Our case study, based on the investigation of daily returns of a portfolio of stocks traded in the US equity markets, shows the degree of robustness and completeness of the information extracted with popular information filtering methods such as the minimum spanning tree and the planar maximally filtered graph. The first method performs a "row bootstrap" whereas the second method performs a "pair bo…