GIRA: a general model for incident risk analysis

Most existing risk analysis methods focus on analysing risks that a system might face throughout its life. However, there is no explicit method for risk analysis during incidents. Approaches such as bow-ties and attack trees provide reliable information about triggers and escalation of incidents, but do not cover risk evaluation. Risk matrices include the entire risk analysis process; however, their risk evaluation approach is oversimplified. This paper presents a General Model for Incident Risk Analysis, which formalises the incident risk analysis process through an influence diagram. Our aim is to provide a decision support model that generates reliable risk information and enhances incident risk evaluation.     

High‐involvement HRM,job satisfaction and productivity: A two wave longitudinal study of a Spanish retail company

The strategic human resource management literature lacks longitudinal studies, and the causal associations between human resource management (HRM) and organisational performance (OP) remain underexplored. We tested cross‐lagged relationships between high‐involvement work systems (HIWS), job satisfaction, and store productivity based on a large longitudinal dataset from the retail sector comprising two waves of data. The first wave (2011) included 6,016 employee responses from 104 stores, and the second wave (2015) included 5,842 employee responses from 94 stores. The quantitative study suggested counterintuitive negative associations. A subsequent qualitative study indicated that the association may have been conditioned by the recessionary action taken by the company in response to financial difficulties. The longitudinal research design, the compilation of data during difficult economic situations, and in a relatively unexplored sector such as the retail industry help to shed some light on the universalism of the HRM‐OP relationship and its boundary conditions.     

On VIX futures in the rough Bergomi model

The rough Bergomi model introduced by Bayer et al. [Quant. Finance, 2015, 1–18] has been outperforming conventional Markovian stochastic volatility models by reproducing implied volatility smiles in a very realistic manner, in particular for short maturities. We investigate here the dynamics of the VIX and the forward variance curve generated by this model, and develop efficient pricing algorithms for VIX futures and options. We further analyse the validity of the rough Bergomi model to jointly describe the VIX and the SPX, and present a joint calibration algorithm based on the hybrid scheme by Bennedsen et al. [Finance Stoch., forthcoming].     

Testing the ‘brain gain’ hypothesis: Micro evidence from Cape Verde

Does emigration really drain human capital accumulation in origin countries? This paper explores a unique household survey designed and conducted to answer this research question. We analyze the case of Cape Verde, a country with allegedly the highest ‘brain drain’ in Africa, despite a marked record of income and human capital growth in recent decades. We propose the first explicit test of ‘brain drain’ arguments, according to which the prospects of own future migration can positively impact educational attainment. Our most conservative estimates using individual specific variation in economic conditions at the destination indicate that a 10 pp increase in the probability of own future migration improves the probability of completing intermediate secondary schooling by nearly 4 pp for individuals who do not migrate before age 16. These findings are robust to the choice of instruments and econometric specification. Counterfactual simulations point to significant human capital gains from lowering migration barriers.     

Belbin's Team Role Model: Development,Validity and Applications for Team Building*

abstract This paper brings together research into and using the team role model developed by Belbin (1981, 1993a ) in an attempt to provide an exhaustive assessment of construct validity in light of the conflicting evidence so far produced. Role theory is used to contextualize the origins of the model. The psychometric properties of the Team Role Self‐Perception Inventory used to assess a person's likely behaviour in a team are examined along with 43 empirical studies that have tested theoretical associations between team roles and other cognitive or behavioural traits. While the evidence is mixed, we conclude that, on balance, the model and its accompanying Inventory have adequate convergent validity. However, strong associations between some team roles are observed, indicating weak discriminant validity among some scales in the Inventory. Through its coverage of important areas of teamworking, the paper contributes to the practitioner and research communities by providing fresh insights into aspects of teamworking and by suggesting new research agendas.     

Labour mobility in the EU: Dynamics,patterns and policies

The continued economic crisis has become a major test for the labour markets of individual member states. Labour mobility within the European Union has the potential to help to reduce labour market pressures and ease economic imbalances. However, a long-term loss of working age population can be detrimental to sending countries. This Forum explores mobility patterns within the European Union and analyses the labour market and welfare effects of labour mobility via case studies of the UK, Poland, Germany and Spain. It also examines a number of its aspects that have important political and institutional relevance for the European Union and its future.     

Deep learning volatility: a deep neural network perspective on pricing and calibration in (rough) volatility models

We present a neural network-based calibration method that performs the calibration task within a few milliseconds for the full implied volatility surface. The framework is consistently applicable throughout a range of volatility models—including second-generation stochastic volatility models and the rough volatility family—and a range of derivative contracts. Neural networks in this work are used in an off-line approximation of complex pricing functions, which are difficult to represent or time-consuming to evaluate by other means. The form in which information from available data is extracted and used influences network performance: The grid-based algorithm used for calibration is inspired by representing the implied volatility and option prices as a collection of pixels. We highlight how this perspective opens new horizons for quantitative modelling. The calibration bottleneck posed by a slow pricing of derivative contracts is lifted, and stochastic volatility models (classical and rough) can be handled in great generality as the framework also allows taking the forward variance curve as an input. We demonstrate the calibration performance both on simulated and historical data, on different derivative contracts and on a number of example models of increasing complexity, and also showcase some of the potentials of this approach towards model recognition. The algorithm and examples are provided in the Github repository GitHub: NN-StochVol-Calibrations.     

Assimilation of immigrants in Spain: A longitudinal analysis

In this paper we use a new panel dataset to analyse the earnings assimilation of immigrants in Spain. We show that immigrants reduce the wage gap relative to natives by 15 pp during the first 5–6 years after arrival, but the earnings differential does not disappear completely. Earnings assimilation is not homogeneous across different nationalities, being faster for South-American and European (new accession countries to EU) immigrants compared to Africans. Finally, we show that human capital gains within the firm as opposed to higher mobility contribute the most to their assimilation process.     

OMITTED VARIABLES IN THE MEASUREMENT OF A LABOR QUALITY INDEX: THE CASE OF SPAIN

Traditional measures of labor quality might have the shortcoming of missing some features of the very important increase in labor utilization within European countries. In particular, we explore the case of Spain. Despite showing one of the most important increases in labor quality in the EU according to standard methods, it also presents a negative TFP growth. The paper shows the importance of considering—on top of observed changes in the composition of the labor force by gender, age, education, tenure, and nationality—changes in both average and relative productivities of those abovementioned socio‐demographic groups over time. We first use a time varying weight index in order to capture the decrease in relative productivities across characteristics. Once this issue is considered the estimated growth of labor quality decreases notably and the index becomes flat between 2002 and 2006. We relate this slowdown to the increasing over‐education of the Spanish workforce in the recent past. We then incorporate a selection model into the labor force. We argue that in the recent past there has been a massive entry of workers with below average unobserved abilities, generating a decrease in quality of labor. Indeed labor quality slightly decreased from 1995 onwards (always increasing without the selection model).     

Exploring the black box in Spanish firms: the effect of the actual and perceived system on employees' commitment and organizational performance

Several studies in strategic human resource management have described a relationship between people-management practices and organizational performance. However, the mediating processes that explain such a relationship remain unexplored. This study examines how both the actual people-management system (assessed by managers) and the perceived system (assessed by employees) influence employees' commitment, and how this in turn contributes to employee and organizational outcomes. Multilevel analyses of a sample of 732 employees from 26 Spanish small and medium-sized enterprises (SMEs) supported a model in which employees' commitment mediates between the actual system and unit-level absenteeism, which in turn has an effect on productivity. Results also showed the importance of the perceived system in attempting to understand the true effect of the actual system on employees' commitment to the organization.