Antipodally symmetric distributions for orientation statistics

The conventional antipodally symmetric Bingham matrix distribution on the Stiefel manifold is generalized. Large sample maximum likelihood estimation and uniformity tests are discussed, and a parametric model for axial orientations (X-shapes) is suggested. A generalization of the Khatri-Mardia matrix distribution is developed to provide a model suitable for hybrids (T-shapes).     

COMMON COMPONENTS OF RISK AND UNCERTAINTY ATTITUDES ACROSS CONTEXTS AND DOMAINS: EVIDENCE FROM 30 COUNTRIES

Attitudes towards risk and uncertainty have been indicated to be highly context‐dependent, and to be sensitive to the measurement technique employed. We present data collected in controlled experiments with 2,939 subjects in 30 countries measuring risk and uncertainty attitudes through incentivized measures as well as survey questions. Our data show clearly that measures correlate not only within decision contexts or measurement methods, but also across contexts and methods. This points to the existence of one underlying “risk preference”, which influences attitudes independently of the measurement method or choice domain. We furthermore find that answers to a general and a financial survey question correlate with incentivized lottery choices in most countries. Incentivized and survey measures also correlate significantly between countries. This opens the possibility to conduct cultural comparisons on risk attitudes using survey instruments.     

关于(口厌)哒族源问题的新探索

本文从历史学、考古学、比较语言学、种族人类学、民俗学等多方面进行研究 ,肯定哒的族源为阿尔泰山周围的呼得和东部天山以北的车师后部。     

Sex selection and fertility in a dynamic model of conception and abortion

This paper investigates the effect of prenatal sex selection on fertility through a stochastic dynamic model with uncertainty in conception as well as in gender, where a woman makes decisions on conception and abortion with or without gender detection tests (i.e. sex-selective or sex-unselective abortion). The paper shows that, when the cost of gender detection test falls, the sex ratio at birth rises due to more selective abortions, but fertility can rise or fall with rising sex ratio. Fertility may rise (fall) if there are more (less) women giving up unselective abortions for selective abortions than women giving up childbirths without test for selective abortions. Similarly the paper shows that the sex ratio can rise or fall, when fertility decreases as the cost of children increases. I test these propositions as well as their implications against micro survey data on the pregnancy history of Korean women.Responsible editor: Junsen Zhang.     

The value of a firm’s engagement in ESG practices: Are we looking at the right side?

Firms allocate many resources to environmental, social, and governance (ESG) issues and to growth options as if they were independent sources of value. Challenging this view, this paper explores the interplay of a firm's engagement in ESG practices and growth options in determining its total value. We draw upon real options reasoning to explain how ESG practices can carry two opposite (trust-enhancing and risk-reducing) forces, driving an inverted U-form relationship between ESG performance and growth options value. Moreover, we argue that ESG performance and growth options are likely to build substitutive insurance mechanisms which might exert a negative moderating effect of growth options on the relationship between ESG performance and a firm's total value. Empirical analyses of ESG scores and growth options values on a panel of U.S. firms from 2009 to 2018 provide substantial support for our hypotheses. Our results show that the inverted U-form relationship between ESG performance and growth options value becomes stronger for the environmental and social pillars. Our evidence on the moderating effect of growth option values also provides valuable insights for interpreting prior conflicting empirical evidence on the association between ESG performance and a firm's total value.     

Exchange rates and the Swiss economy

Safe haven capital inflows and other factors have caused the Swiss franc to appreciate and posed challenges for policymakers. We find that these exchange rate changes do not affect the volume of exports from Switzerland’s most advanced sectors, pharmaceuticals and watches, but do matter for exports of medium-high-technology products such as capital goods and machinery. We also report that appreciations do not affect stock prices and goods prices for the pharmaceutical and watch industries but cause both stock and goods prices to tumble for the capital goods and machinery sectors. We draw many policy lessons from these findings for Switzerland and for the rest of the world.     

Bayesian temporal density estimation with autoregressive species sampling models

We propose a novel Bayesian nonparametric (BNP) model, which is built on a class of species sampling models, for estimating density functions of temporal data. In particular, we introduce species sampling mixture models with temporal dependence. To accommodate temporal dependence, we define dependent species sampling models by modeling random support points and weights through an autoregressive model, and then we construct the mixture models based on the collection of these dependent species sampling models. We propose an algorithm to generate posterior samples and present simulation studies to compare the performance of the proposed models with competitors that are based on Dirichlet process mixture models. We apply our method to the estimation of densities for the price of apartment in Seoul, the closing price in Korea Composite Stock Price Index (KOSPI), and climate variables (daily maximum temperature and precipitation) of around the Korean peninsula.     

Minimum projection uniformity for computer experiment with quantitative factors

Computer experiments involving quantitative factors at high levels are becoming more and more important in the study of complex experiments arising in the area of science and engineering. Uniform designs are found to be widely applicable in computer experiments in the form of space-filling designs. In this paper, the projection uniformity for quantitative designs is studied under wrap-around $L_2$-discrepancy. A lower bound of uniformity pattern for general asymmetric designs is provided, which can be used to serve as a benchmark for both comparing different designs and also to determine the optimal design. As a byproduct, a lower bound of wrap-around $L_2$-discrepancy measure for the asymmetric design is also obtained. Some illustrative examples and numerical comparisons are also provided for supporting our theoretical results.     

CRITICAL PERIODS DURING CHILDHOOD AND ADOLESCENCE

We identify the ages that constitute sensitive (or critical) periods in children's development towards their adult health status, skills, and human capital. For this, we use data on families migrating into Sweden from countries that are poorer, with less healthy conditions. Late‐life health is proxied by adult height and other adult outcomes. The relation between siblings’ ages at migration and their adult outcomes allows us to estimate the causal effect of conditions at specific childhood ages. We effectively exploit that, for siblings, the migration occurs simultaneously in calendar time but at different developmental stages (ages). We find evidence that the period just before the puberty growth spurt constitutes a critical period for adult height and we find related critical periods for adult cognition, mental health, and education.