ABSTRACT It has been found that the way high-performance coaches lead influences both athletes’ performance and mental health. However, limited research exists on the Social Identity Approach to leadership in elite sports, despite growing interest in coaching science regarding interpersonal behaviours and leadership. This study investigates the empirical links between coaches’ leadership, sport performance and mental health from a social identity approach. One hundred and forty-five elite athletes (M age = 20.6 years; SD = 4.1; 62% women, 38% men) answered questionnaires measuring coaches’ social identity leadership, sport performance satisfaction and mental health. The overall structural equation model (SEM) accounted for 36% and 19% of the variances in athletes’ mental health and mental illness dimensions, respectively. There was a positive association between perceived coaches’ social identity leadership and sport performance satisfaction, explaining 10% of its variance. Coaches’ social identity leadership predicted athletes’ mental health but not mental illness. Sport performance satisfaction positively influenced mental health and negatively impacted mental illness. Fostering a sense of “we” and “us” within elite sport training groups is instrumental in promoting sport performance satisfaction and, consequently, enhancing the mental health of athletes. Coaching educational courses may benefit from social identity leadership in interpersonal behaviours.

ABSTRACT This study examines the influence of dual ownership on managerial efficiency using panel data from a dataset of U.S. firms spanning 1996 to 2017. Our findings indicate that dual ownership negatively affects managerial efficiency, demonstrating diminishing productivity in resource utilization when dual ownership is present or increases. Cross-sectional analyses suggest that the adverse effect of dual holders on managerial efficiency is more pronounced in dual-held firms with weaker corporate governance and greater financial constraints. Additional analyses, including propensity score matching, change specifications, Lewbel’s instrumental variable approach, and alternative measures of managerial efficiency, corroborate our findings.

ABSTRACT This study aims to identify distinct small-scale temporary patterns between the river discharge and suspended sediment load for the main tropical rivers using continuous wavelet transform. The strong annual, and irregular semiannual with few quarterly and interdecadal variabilities are observed in river discharge and sediment load. The wavelet coherence discloses that the strongest in-phase coherence relationships exist between total suspended sediment and streamflow. The methodology for identifying the primary climate factors that integrate the Partial wavelet coherence (PWC), Multiple wavelet coherence (MWC), and Quadruple wavelet coherence (QMWC) techniques is presented. The results show that the ENSO is the major regulator of streamflow followed by IOD and PDO. The chosen rivers show a statistically significant ( p ≤ 0.05 ) descending trend in sediment load but no significant positive or negative trend in river discharge. This could be due to regional sediment storage and large-scale stream events affecting the sediment transport dynamics.

ABSTRACT This study examines the reliability of the Environmental Impact Statements (EISs) in Peru, focusing on projects predicted to have high negative impacts. It highlights the discrepancy between the expected and the estimated impacts in EISs, revealing a general trend of underestimating the environmental significance of projects, particularly in areas free from industrial activities. The study critiques the application of the Gomez Orea Method, originally successful under Spanish regulations but problematic in its Peruvian applications, as evidenced by inconsistencies in the methodologies and a lack of bibliographic and regulatory support for the indicators used. The analysis covers seven EISs involving hydroelectric and mineral exploitation projects. It identifies a recurrent pattern where despite the significant potential impacts of these projects on water quality, ecosystems, and biodiversity, the impacts are predominantly classified as ‘Compatible’ or low. This underestimation results in 97.37% of impacts being categorized as low, contradicting the projects’ initial high-risk classification. Moreover, the study compares the Gomez Orea Method with the Conesa Method, a more conservative approach, finding significant methodological differences affecting impact significance estimations. The study advocates for enhanced Environmental Impact Assessment practices in Peru, suggesting the adoption of more conservative assessment methods to accurately gauge and mitigate environmental impacts.

ABSTRACT We consider how to facilitate a dynamically-priced premium service option that enables customer parties to shorten their wait in a queue. Offering such a service requires that some of a business’s capacity be reserved continuously and kept ready for premium customers. In tandem with capacity reservation, pricing must be coordinated. Hence, a joint dynamic pricing and capacity allocation problem lies at the heart of this service. We propose a conceptual solution architecture and employ Proximal Policy Optimization (PPO) for dynamic pricing and capacity allocation to maximize total revenue. Simulation experiments over multiple scenarios compared PPO against a human-engineered policy and a baseline policy having no premium option. The human-engineered policy led to significantly greater revenues than the baseline policy in each scenario, illustrating the potential increase in revenues afforded by this concept. The PPO agent substantially improved upon the human-engineered policy advantage, with improvements ranging from 28% to 161%.