Using experiments and expert judgment to model catchability of Pacific rockfishes in trawl surveys, with application to bocaccio (Sebastes paucispinis) off British Columbia

The time series of abundance indices for many groundfish populations, as determined from trawl surveys, are often imprecise and short, causing stock assessment estimates of abundance to be imprecise. To improve precision, prior probability distributions (priors) have been developed for parameters in stock assessment models by using meta-analysis, expert judgment on catchability, and empirically based modeling. This article presents a synthetic approach for formulating priors for rockfish trawl survey catchability (qgross). A multivariate prior for qgross for different surveys is formulated by using 1) a correction factor for bias in estimating fish density between trawlable and untrawlable areas, 2) expert judgment on trawl net catchability, 3) observations from trawl survey experiments, and 4) data on the fraction of population biomass in each of the areas surveyed. The method is illustrated by using bocaccio (Sebastes paucipinis) in British Columbia. Results indicate that expert judgment can be updated markedly by observing the catch-rate ratio from different trawl gears in the same areas. The marginal priors for qgross are consistent with empirical estimates obtained by fitting a stock assessment model to the survey data under a noninformative prior for qgross. Despite high prior uncertainty (prior coefficients of variation ≥0.8) and high prior correlation between qgross, the prior for qgross still enhances the precision of key stock assessment quantities

The Impact of Leader's Humor on Employees' Creativity: The Moderating Role of Trust in Leader

The purpose of this study is to examine how leaders humor styles influence employee creativity, and the moderating effects of trust in leader on the relationships between leaders humor styles and employees creativity. The results using 316 valid leader-subordinates pairs (71 leaders and 316 subordinates) from five telecommunication companies in South Korea showed that leaderself-enhancing humor was positively associated with subordinates individual creativity, and leaders aggressive humor was negatively associated with subordinates individual creativity. In addition, trust in leader significantly moderated the relationship between self-enhancing humor and employee creativity. Specifically, the relationship between self-enhancing humor and employee creativity became stronger as trust in leader increased

Social tie, social capital, and social behavior: Toward an integrative model of informal exchange

What is the unique nature of social capital that differentiates itself from other forms of capital? How should we conceptualize and operationalize social capital? What are the major drivers and outcomes of social capital? To address the three questions, I apply the duality lens—the perspective of regarding each entity as a paradox consisting of two contrasting yet interdependent components—to social capital for an integrative model of informal exchange. The focus of this paper is on the duality relationship between the content variables (social tie, social capital, social behavior along two basic dimensions: trust for tie strength and option for network structure) and the process variables (antecedent, content, process, and consequence) toward a geocentric framework of formal–informal exchange. I intend to make two contributions. First, the conceptualization and operationalization of social capital is developed from the duality lens of formal–informal exchange so as to identify the unique nature of social capital as an informal entity. Second, a holistic, dynamic, and dialectic model of social capital is provided to explore the causal links between various elements related to social capital. Copyright Springer Science+Business Media, LLC 2007Social capital, Trust, Option, Tie strength, Network structure, Informal exchange,

Ezetimibe added to statin therapy after acute coronary syndromes

BACKGROUND: Statin therapy reduces low-density lipoprotein (LDL) cholesterol levels and the risk of cardiovascular events, but whether the addition of ezetimibe, a nonstatin drug that reduces intestinal cholesterol absorption, can reduce the rate of cardiovascular events further is not known. METHODS: We conducted a double-blind, randomized trial involving 18,144 patients who had been hospitalized for an acute coronary syndrome within the preceding 10 days and had LDL cholesterol levels of 50 to 100 mg per deciliter (1.3 to 2.6 mmol per liter) if they were receiving lipid-lowering therapy or 50 to 125 mg per deciliter (1.3 to 3.2 mmol per liter) if they were not receiving lipid-lowering therapy. The combination of simvastatin (40 mg) and ezetimibe (10 mg) (simvastatin-ezetimibe) was compared with simvastatin (40 mg) and placebo (simvastatin monotherapy). The primary end point was a composite of cardiovascular death, nonfatal myocardial infarction, unstable angina requiring rehospitalization, coronary revascularization ( 6530 days after randomization), or nonfatal stroke. The median follow-up was 6 years. RESULTS: The median time-weighted average LDL cholesterol level during the study was 53.7 mg per deciliter (1.4 mmol per liter) in the simvastatin-ezetimibe group, as compared with 69.5 mg per deciliter (1.8 mmol per liter) in the simvastatin-monotherapy group (P<0.001). The Kaplan-Meier event rate for the primary end point at 7 years was 32.7% in the simvastatin-ezetimibe group, as compared with 34.7% in the simvastatin-monotherapy group (absolute risk difference, 2.0 percentage points; hazard ratio, 0.936; 95% confidence interval, 0.89 to 0.99; P = 0.016). Rates of pre-specified muscle, gallbladder, and hepatic adverse effects and cancer were similar in the two groups. CONCLUSIONS: When added to statin therapy, ezetimibe resulted in incremental lowering of LDL cholesterol levels and improved cardiovascular outcomes. Moreover, lowering LDL cholesterol to levels below previous targets provided additional benefit