Shedding light on the aim of stock options: a literature review

Stock options (hereafter SOs) have been extensively investigated by the literature. The debate has been mainly grounded in the agency theory that has interpreted these tools as mechanisms to align the conflicting interests of managers and owners towards the shareholder value maximization. However, the latest empirical evidence suggests that SOs are often used by opportunistic managers to extract rents to the detriment of shareholders. In addition, literature identifies the perceived cost as a further theoretical lens to interpret the use of SOs. Despite the growing interest around the topic, the research is still fragmented and fails to present a comprehensive picture on the factors that affect the aim of SOs. Our literature review attempts to fill this gap by providing a systematization of the studies on the topic. The paper concludes by presenting the theoretical and practical implications of the study and suggesting directions for future research.     

BMS: An improved Dunn index for Document Clustering validation

Abstract

Document Clustering aims at organizing a large quantity of unlabeled documents into a smaller number of meaningful and coherent clusters. One of the main unsolved problems in the literature is the lack of a reliable methodology to evaluate the results, although a wide variety of validation measures has been proposed. Validation measures are often unsatisfactory with numerical data, and even underperforming with textual data. Our attention focuses on the use of cosine similarity into the clustering process. A new measure based on the same criterion is here proposed. The effectiveness of the proposal is shown by an extensive comparative study.     

On the impact of contaminations in graphical Gaussian models

This paper analyzes the impact of some kinds of contaminant on model selection in graphical Gaussian models. We investigate four different kinds of contaminants, in order to consider the effect of gross errors, model deviations, and model misspecification. The aim of the work is to assess against which kinds of contaminant a model selection procedure for graphical Gaussian models has a more robust behavior. The analysis is based on simulated data. The simulation study shows that relatively few contaminated observations in even just one of the variables can have a significant impact on correct model selection, especially when the contaminated variable is a node in a separating set of the graph.     

Does speaking or writing Italian make differences?

Although researchers acknowledge the key role of language in immigrant integration, empirical analyses on how proficiency in Italian differently shape the social outcomes of immigrants living in Italy are limited. Using the Italian Survey on Social Condition and Integration of Foreign Citizens, we model individual demographic and linguistic patterns, setting apart communication ability from other linguistic skills. Clustering immigrants by mother tongue linguistic group, we leverage the age at arrival and knowledge of Italian during childhood to address endogeneity. Findings reveal how deficiencies in Italian affect integration outcomes of immigrants: the magnitude of effects due to poor proficiency in communication (understanding and speaking) is larger when compared to more formal linguistic skills (reading and writing). Women suffer from higher linguistic barriers in the employment outcomes than men do. Results give empirical argumentations to support immigrant integration through the development of language-training programmes in destination languages tailored on immigrants' demographic and linguistic profiles.     

Refugee protection in the region: A survey and evaluation of current trends

Protection in the region has rapidly become a favoured durable solution to refugee situations and the hallmark of all current policies. These initiatives reflect changes in humanitarian approaches that have taken place over the past decades as the focus has shifted towards the resilience of crisis-affected communities and the need to enable their self-reliance. Despite the strong logic that this change will bring about more dignified solutions, the approach is easily instrumentalized. This instrumentalization is particularly evident where resilience humanitarianism meets security-migration politics. This paper focuses on the efforts of the European Union and a number of its member states to advance so-called protection in the region. The paper reviews the characteristics of these policies, highlights a number of risks and defines some known and lesser known implications of this approach.     

Schooling choices and parental migration. Evidence from Mexico

Review of Economics of the Household - This paper investigates the role of parental absence due to migration on education and labor market outcomes of children left behind in Mexico. I look at the...     

Comparing COVID-19 fatality across countries: a synthetic demographic indicator

Journal of Population Research - The case fatality rate (CFR) is one of the most important measures for monitoring disease progression and evaluating appropriate policy health measures over the...