Co-dependency and myth

Timmen Cernak’s use of Ovid’s mythological account of Narcissus and Echo as a classic case of co-dependence is critically analyzed against other interpretations. Simultaneous consideration is given to whether and to what extent the clinical concept of co-dependency has been confounded with the psychology of women in a male-oriented society. The complex and ambiguous symbolism of myth demands separation of myth from reality in describing the symptoms, etiology, and treatment of clinical co-dependence.     

Firm age dynamics and causes of corporate bankruptcy: age dependent explanations for business failure

Review of Managerial Science - Theories of organizational failure predict that reasons for corporate demise may differ by firm age and life cycle stage. However, large-scale empirical studies that...     

SKILL‐BIASED TECHNOLOGICAL CHANGE,UNEMPLOYMENT, AND BRAIN DRAIN

We develop a model of directed technology adoption, frictional unemployment, and migration to examine the effects of a change in skill endowments on the wages, employment rates, and emigration rates of skilled and unskilled workers. We find that, depending on the elasticity of substitution between skilled and unskilled workers and the elasticity of the matching function, an increase in the skill ratio can reduce both the relative unemployment rate and the relative emigration rate (brain drain) of skilled workers. We provide numerical simulations to support our findings and show that the effects are empirically relevant and potentially sizable.     

Transformational Leadership and Volunteer Firefighter Engagement

This study explores the relationship between transformational leadership and volunteer firefighter engagement. Using responses from 213 volunteer firefighters, structural equation modeling reveals a positive relationship between transformational leadership and volunteer engagement, which is mediated by both group identification and perceived social impact. In addition, higher volunteer engagement is positively related to a firefighter's intention to continue volunteering and to recruit others. Taken together, the results indicate that transformational leaders achieve positive volunteer outcomes by strengthening the organizational ties of volunteers and by connecting volunteers with the prosocial impact of their work. Theoretical implications for transformational leadership research in volunteer settings as well as practical recommendations for a sustainable volunteer management are provided.     

Gradient boosting for distributional regression: faster tuning and improved variable selection via noncyclical updates

We present a new algorithm for boosting generalized additive models for location, scale and shape (GAMLSS) that allows to incorporate stability selection, an increasingly popular way to obtain stable sets of covariates while controlling the per-family error rate. The model is fitted repeatedly to subsampled data, and variables with high selection frequencies are extracted. To apply stability selection to boosted GAMLSS, we develop a new “noncyclical” fitting algorithm that incorporates an additional selection step of the best-fitting distribution parameter in each iteration. This new algorithm has the additional advantage that optimizing the tuning parameters of boosting is reduced from a multi-dimensional to a one-dimensional problem with vastly decreased complexity. The performance of the novel algorithm is evaluated in an extensive simulation study. We apply this new algorithm to a study to estimate abundance of common eider in Massachusetts, USA, featuring excess zeros, overdispersion, nonlinearity and spatiotemporal structures. Eider abundance is estimated via boosted GAMLSS, allowing both mean and overdispersion to be regressed on covariates. Stability selection is used to obtain a sparse set of stable predictors.