Spatiotemporal Associations between Local Safety Level Index and COVID-19 Infection Risks across Capital Regions in South Korea

This study aims provide understanding of the local-level spatiotemporal evolution of COVID-19 spread across capital regions of South Korea during the second and third waves of the pandemic (August 2020~June 2021). To explain transmission, we rely upon the local safety level indices along with latent influences from the spatial alignment of municipalities and their serial (temporal) correlation. Utilizing a flexible hierarchical Bayesian model as an analytic operational framework, we exploit the modified BYM (BYM2) model with the Penalized Complexity (PC) priors to account for latent effects (unobserved heterogeneity). The outcome reveals that a municipality with higher population density is likely to have an elevated infection risk, whereas one with good preparedness for infectious disease tends to have a reduction in risk. Furthermore, we identify that including spatial and temporal correlations into the modeling framework significantly improves the performance and explanatory power, justifying our adoption of latent effects. Based on these findings, we present the dynamic evolution of COVID-19 across the Seoul Capital Area (SCA), which helps us verify unique patterns of disease spread as well as regions of elevated risk for further policy intervention and for supporting informed decision making for responding to infectious diseases.

Exploring Unobserved Heterogeneity in Cyclists’ Occupying Motorized Vehicle Lane Behaviors at Different Bike Facility Configurations

Cyclists occupying motorized vehicle lanes disrupt road traffic order and increase collisions. Exploring the contributing factors could help develop countermeasures to regulate such behaviors. The purpose of this study is to explore the intrinsic features influencing the behavior of cyclists in occupying motorized vehicle lanes at different bicycle facilities. We investigated a total of 34,631 cycling behavior samples in the urban area of Pingdingshan, China. A Bayesian random parameter logit model was used to account for the unobserved heterogeneous effects. The experimental results of all bike facilities demonstrate that the bike type, dividing strip type, bike lane width, temporary on-street parking, and whether it is a working day significantly affect cyclists’ occupying motorized vehicle lane behaviors. Factors associated with unobserved heterogeneity are age, barriers dividing strip, vehicle lane numbers, bike volume, vehicle volume, and daily recording time intervals. Comparing the estimated model of five type bike lane facilities across different dividing strips, we find that cyclists have a significantly different occupying probability and the heterogeneity factors of the various bike facilities also have their focus. When the non-motorized road conditions become more open, the cyclist behavior becomes more random and the heterogeneity factors become broader.

On directors’ compensation: a multilevel analysis of Spanish listed companies

This study analyzes the determinants of the annual compensation of directors belonging to the boards of the Spanish companies that constitute the IBEX 35 stock index. We investigate the importance of observed and unobserved heterogeneity in explaining director compensation. Based on a three-level mixed effect model, our analysis includes time-invariant random effects at company and manager level as determinants of director pay. We find that company effects explain 30% of the variation in director pay, while company and director effects taken together explain 77% of that variation. Our findings suggest that the characteristics of the company, in terms of activity sector, size and financial performance, and the professional attributes of the director (especially the role within the board), influence the compensation received. In addition, some directors and companies show random effects (either positive or negative) that significantly separate them from the expected compensation estimated from the fixed part of the model.

Childhood hearing impairment and fertility in Norway

There is a lack of studies assessing how hearing impairment relates to reproductive outcomes. We examined whether childhood hearing impairment (HI) affects reproductive patterns based on longitudinal Norwegian population level data for birth cohorts 1940–1980. We used Poisson regression to estimate the association between the number of children ever born and HI. The association with childlessness is estimated by a logit model. As a robustness check, we also estimated family fixed effects Poisson and logit models. Hearing was assessed at ages 7, 10 and 13, and reproduction was observed at adult ages until 2014. Air conduction hearing threshold levels were obtained by pure-tone audiometry at eight frequencies from 0.25 to 8 kHz. Fertility data were collected from Norwegian administrative registers. The combined dataset size was N = 50,022. Our analyses reveal that HI in childhood is associated with lower fertility in adulthood, especially for men. The proportion of childless individuals among those with childhood HI was almost twice as large as that of individuals with normal childhood hearing (20.8% vs. 10.7%). The negative association is robust to the inclusion of family fixed effects in the model that allow to control for the unobserved heterogeneity that are shared between siblings, including factors related to the upbringing and parent characteristics. Less family support in later life could add to the health challenges faced by those with HI. More attention should be given to how fertility relates to HI.

Como a Estratégia como Prática pode Habilitar a Inovação sob Influência do Dinamismo Ambiental?

ABSTRACT Purpose: the objective of this study was to analyze innovation in Brazilian organizations when enabled through SIS, in the strategy-as-practice approach, on the influence of moderating environmental dynamism. Methods: we performed structural equation modeling using the statistical technique of partial least squares path modeling (PLS-PM) and post hoc analysis to identify unobserved heterogeneity, with a sample of 256 Brazilian companies from different sectors. Results: the results revealed that the SIS had a strong and significant influence on the innovation of exploitation and exploration. The environmental uncertainty of dynamism moderation was not present in the relationship between SIS and the innovation of exploitation. However, SIS showed a strong and significant influence on innovation of exploration in high levels of dynamism. The existence of unobserved heterogeneity was identified for two segments of the sample, demonstrating a strong path effect between SIS and innovation of exploration and exploitation on the high presence of dynamism in service companies with a size greater than 500 employees. Conclusions: the study contributed to the extension of the strategy-as-practice and innovation literature, by identifying SIS as an alternative in the planning process to enable innovation in the organization, in environments with a high rate of change and unpredictability.

How Do Financial Constraints and Financial Crises Matter in Cash Management?

This chapter investigates how financial constraints and financial crises affect the cash policy of firms. Using a sample of 157,505 firm-years from 26 developing Asian economies from 1991 to 2016, firm fixed effects are employed to mitigate unobserved heterogeneity. Empirical findings show that financially constrained firms have higher cash than financially unconstrained firms, which is in line with the precautionary motive and transaction motive of cash. The picture changes with the rise of financial crises. While financially constrained firms have lower cash before the 1997-1998 Asian financial crisis, they increase their cash level more after the 2008-2009 global financial crisis. Overall, managers need to consider the exogenous shocks to enhance their liquidity management. Also, investors should consider the financial crises, firm size, firm constraint, and dividend payment status when determining when and where to invest.

How can Strategy-as-Practice Enable Innovation under the Influence of Environmental Dynamism?

ABSTRACT Purpose: the objective of this study was to analyze innovation in Brazilian organizations when enabled through SIS, in the strategy-as-practice approach, on the influence of moderating environmental dynamism. Methods: we performed structural equation modeling using the statistical technique of partial least squares path modeling (PLS-PM) and post hoc analysis to identify unobserved heterogeneity, with a sample of 256 Brazilian companies from different sectors. Results: the results revealed that the SIS had a strong and significant influence on the innovation of exploitation and exploration. The environmental uncertainty of dynamism moderation was not present in the relationship between SIS and the innovation of exploitation. However, SIS showed a strong and significant influence on innovation of exploration in high levels of dynamism. The existence of unobserved heterogeneity was identified for two segments of the sample, demonstrating a strong path effect between SIS and innovation of exploration and exploitation on the high presence of dynamism in service companies with a size greater than 500 employees. Conclusions: the study contributed to the extension of the strategy-as-practice and innovation literature, by identifying SIS as an alternative in the planning process to enable innovation in the organization, in environments with a high rate of change and unpredictability.