Explaining the diversification discount

Diversified firms trade at a discount relative to similar single-segment firms. We argue in this paper that this observed discount is not per se evidence that diversification destroys value. Firms choose to diversify. Firm characteristics, which make firms diversify might also cause them to be discounted. Not taking into account these firm characteristics might wrongly attribute the observed discount to diversification. Data from the Compustat Industry Segment File from 1978 to 1996 are used to select a sample of single segment and diversifying firms. We use three alternative econometric techniques to control for the endogeneity of the diversification decision. All three methods suggest the presence of self-selection in the decision to diversify and a negative correlation between firm's choice to diversify and firm value. The diversification discount always drops, and sometimes turns into a premium, when we control for the endogeneity of the diversification decision. We do a similar analysis in a sample of refocusing firms. Again, some evidence of self-selection by firms exists and we now find a positive correlation between firm's choice to refocus and firm value. These results consistently suggest the importance of taking the endogeneity of the diversification status into account, in analyzing its effects on firm value.Diversification discount;

Percolation-induced exponential scaling in the large current tails of random resistor networks

There is a renewed surge in percolation-induced transport properties of diverse nano-particle composites (cf. RSC Nanoscience & Nanotechnology Series, Paul O'Brien Editor-in-Chief). We note in particular a broad interest in nano-composites exhibiting sharp electrical property gains at and above percolation threshold, which motivated us to revisit the classical setting of percolation in random resistor networks but from a multiscale perspective. For each realization of random resistor networks above threshold, we use network graph representations and associated algorithms to identify and restrict to the percolating component, thereby preconditioning the network both in size and accuracy by filtering {\it a priori} zero current-carrying bonds. We then simulate many realizations per bond density and analyze scaling behavior of the complete current distribution supported on the percolating component. We first confirm the celebrated power-law distribution of small currents at the percolation threshold, and second we confirm results on scaling of the maximum current in the network that is associated with the backbone of the percolating cluster. These properties are then placed in context with global features of the current distribution, and in particular the dominant role of the large current tail that is most relevant for material science applications. We identify a robust, exponential large current tail that: 1. persists above threshold; 2. expands broadly over and dominates the current distribution at the expense of the vanishing power law scaling in the small current tail; and 3. by taking second moments, reproduces the experimentally observed power law scaling of bulk conductivity above threshold

Functional adaptivity for digital library services in e-infrastructures: the gCube approach

We consider the problem of e-Infrastructures that wish to reconcile the generality of their services with the bespoke requirements of diverse user communities. We motivate the requirement of functional adaptivity in the context of gCube, a service-based system that integrates Grid and Digital Library technologies to deploy, operate, and monitor Virtual Research Environments defined over infrastructural resources. We argue that adaptivity requires mapping service interfaces onto multiple implementations, truly alternative interpretations of the same functionality. We then analyse two design solutions in which the alternative implementations are, respectively, full-fledged services and local components of a single service. We associate the latter with lower development costs and increased binding flexibility, and outline a strategy to deploy them dynamically as the payload of service plugins. The result is an infrastructure in which services exhibit multiple behaviours, know how to select the most appropriate behaviour, and can seamlessly learn new behaviours

A Quantitative Study on Indigenous Medicinal Plants used by Tribes of Kerala

A quantitative study of indigenous medicinal plants with detailed documentationamong tribal people was carried out in Idukki Wildlife Sanctuary, Idukki District, Kerala State. Nine tribal settlements were selected for the study based on the area and availability of information. Accordingly 120 informants were selected purposively. Direct observation, semi structured interview and group discussion were used to collect the data from the informants. The collected data was analysed using Micro-soft Excel spreadsheet 2010 and summarized using descriptive statistical methods. Five different quantitative statistical tools such as Relative Frequency of Citation (RFC), Use value (UV), Relative Importance Index (RI), Relative Importance Index (RI), Fidelity Level (FL) and Informants’ Consensus Factor (ICF) were analysed with score. Acacia caesia (L.) Wild had the highest RFC with rank I,; Adhatoda beddomei C.B. Clarke gave the highest use value with the maximum number of medicinal purposes (four).  A majority of species were found to be most used among the community. The highest level of ICF was obtained for urological ailments (UA) followed by gynaecological ailments (GAA) and Dermatological ailments (DA) in that order

General no-go condition for stochastic pumping

The control of chemical dynamics requires understanding the effect of time-dependent transition rates between states of chemo-mechanical molecular configurations. Pumping refers to generating a net current, e.g. per period in the time-dependence, through a cycle of consecutive states. The working of artificial machines or synthesized molecular motors depends on it. In this paper we give short and simple proofs of no-go theorems, some of which appeared before but here with essential extensions to non-Markovian dynamics, including the study of the diffusion limit. It allows to exclude certain protocols in the working of chemical motors where only the depth of the energy well is changed in time and not the barrier height between pairs of states. We also show how pre-existing steady state currents are in general modified with a multiplicative factor when this time-dependence is turned on.Comment: 8 pages; v2: minor changes, 1 reference adde

The Italian dependency annotated corpus developed for the CoNLL-2007 Shared Task

This document illustrates the Italian dependency annotated corpus developed for the CoNLL-X Shared Task (henceforth referred to as ISST-CoNLL). In particular, it provides information on the background resource, the way the CoNLL Italian resource has been designed and developed, and finally documents the adopted annotation scheme

In vitro Cortical Network Firing is Homeostatically Regulated: A Model for Sleep Regulation.

Prolonged wakefulness leads to a homeostatic response manifested in increased amplitude and number of electroencephalogram (EEG) slow waves during recovery sleep. Cortical networks show a slow oscillation when the excitatory inputs are reduced (during slow wave sleep, anesthesia), or absent (in vitro preparations). It was recently shown that a homeostatic response to electrical stimulation can be induced in cortical cultures. Here we used cortical cultures grown on microelectrode arrays and stimulated them with a cocktail of waking neuromodulators. We found that recovery from stimulation resulted in a dose-dependent homeostatic response. Specifically, the inter-burst intervals decreased, the burst duration increased, the network showed higher cross-correlation and strong phasic synchronized burst activity. Spectral power below <1.75 Hz significantly increased and the increase was related to steeper slopes of bursts. Computer simulation suggested that a small number of clustered neurons could potently drive the behavior of the network both at baseline and during recovery. Thus, this in vitro model appears valuable for dissecting network mechanisms of sleep homeostasis

Breaking down the language of racism:a computerised linguistic analysis of racist groups’ self-defining online statements

The Internet represents a powerful tool for racist groups to build a sense of group consciousness and promote their cause. In the current study, we examined the language used by racist (n = 87), anti-racist (n = 50), and nonactivist (n = 1379) groups when describing their self-defining beliefs online. We used computerized linguistic analysis software to measure psychological indicators and antecedents of group consciousness and to examine the persuasive techniques used in online group communication. Racist and anti-racist groups were similar on some linguistic indicators of group consciousness (e.g., use of words reflecting perceived injustice), but differed on others (e.g., use of words reflecting group identification). Linguistic indicators of antecedents of group consciousness (moral foundations and focus on religion) differed across groups, with racist groups focused more on purity, respect for authority, and religion, and less on fairness than anti-racist groups. Racist groups also used less cognitively complex language than nonactivist groups (but similar levels to anti-racist groups). Our results contribute to understanding how racist groups promote their self-defining beliefs online, and identify several key factors that should be considered when designing policies to reduce racist groups' growth and impact

Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This Letter of Intent presents the MeV-GeV DM discovery potential for a 1 m$^3$ segmented plastic scintillator detector placed downstream of the beam-dump at one of the high intensity JLab experimental Halls, receiving up to 10$^{22}$ electrons-on-target (EOT) in a one-year period. This experiment (Beam-Dump eXperiment or BDX) is sensitive to DM-nucleon elastic scattering at the level of a thousand counts per year, with very low threshold recoil energies ($\sim$1 MeV), and limited only by reducible cosmogenic backgrounds. Sensitivity to DM-electron elastic scattering and/or inelastic DM would be below 10 counts per year after requiring all electromagnetic showers in the detector to exceed a few-hundred MeV, which dramatically reduces or altogether eliminates all backgrounds. Detailed Monte Carlo simulations are in progress to finalize the detector design and experimental set up. An existing 0.036 m$^3$ prototype based on the same technology will be used to validate simulations with background rate estimates, driving the necessary R$\&$D towards an optimized detector. The final detector design and experimental set up will be presented in a full proposal to be submitted to the next JLab PAC. A fully realized experiment would be sensitive to large regions of DM parameter space, exceeding the discovery potential of existing and planned experiments by two orders of magnitude in the MeV-GeV DM mass range.Comment: 28 pages, 17 figures, submitted to JLab PAC 4