森林资源资产组合随机控制模型及决策

在界定了森林生态资产与森林资源资产组合概念的基础上,构建和模拟了基于随机控制理论的森林资源资产组合模型,为森林经营管理者提出了相应的结论和建议:森林经营管理者可以根据最优采伐量与木材价格、补偿价格、成本系数、税率、贴现率、生长率等参数之间的关系,获得在市场经济变动条件下的最优森林资产组合,以保证森林资产净收益的稳定增长。     

Learning,large deviations and rare events

We examine the role of generalized stochastic gradient constant gain (SGCG) learning in generating large deviations of an endogenous variable from its rational expectations value. We show analytically that these large deviations can occur with a frequency associated with a fat-tailed distribution even though the model is driven by thin-tailed exogenous stochastic processes. We characterize these large deviations, driven by sequences of consistently low or consistently high shocks and then apply our model to the canonical asset pricing framework. We demonstrate that the tails of the stationary distribution of the price–dividend ratio will follow a power law.     

Soft drink prices,sales, body mass index and diabetes: Evidence from a panel of low-, middle- and high-income countries

We take advantage of four different cross-country datasets containing data on 78 countries for the period 1999–2014, in order to assess the relationship of carbonated soft drinks’ sales, as well as their prices, with body mass index (BMI), overweight, obesity and diabetes. Using an ecological study design and multivariate regression longitudinal estimation approaches, we find that carbonated soft drink sales were significantly positively related to BMI, overweight and obesity – but only in the low and lower-middle income countries. This finding was robust to a number of sensitivity and falsification checks. In this sub-sample, an increase in per capita soft drink sales by 1 litre per year was related to an increase of BMI by about 0.009 kg/m² (p < 0.1).. This is a small effect, implying that halving annual consumption per capita in this group of countries would result in a drop of BMI by only about 0.03 kg/m². Although soft drink prices were negatively related to weight-related outcomes in the sample of higher middle income and high income countries, this finding was not robust to falsification checks. The results thus suggest that sales restrictions to steer consumers away from soft drinks could indeed have a beneficial health effects in poorer countries, although the effect magnitude appears to be very small. However, given potential limitations of using ecological research design, results from individual level studies would be required to further ascertain the role of soft drink sales and prices in obesity and diabetes.     

A new assessment of economic integration in East Asia: Application of an industry-specific G-PPP model

It is well known that intra-industry trade and cross-border production networks have promoted economic growth and regional integration in East Asia. However, regional supply and production chains may have been formed differently across industries, reflecting different degrees and a different scope of regional economic linkages at an industry level. This paper makes a threefold contribution. First, to assess industry-level differences, this study adopts the generalized purchasing power parity (G-PPP) model using industry-specific producer prices. Second, the momentum threshold autoregressive (M-TAR) model is employed to allow for possible nonlinearity arising from the dynamic nature of regional economic growth and development. Third, the Granger causality test is also conducted to assess whether regional economies have autonomously integrated. The empirical results reveal that economic integration has progressed more autonomously in the electrical industry, as well as in the transportation equipment industry, as China and the ASEAN countries have become the final destination markets for finished products in these two industries.     

Fractional integration and cointegration in merger and acquisitions in the US petroleum industry

This article employs methodologies based on fractional integration and cointegration to analyse the time-series properties of merger and acquisitions (M&A) activity and crude oil prices in the US from 1980 to 2012. Our results indicate that an increase in the crude oil price produces a significant increase in the M&A data between 2 and 3 months after the initial shock.     

How can investors build a better portfolio in small open economies? Evidence from Asia’s Four Little Dragons

This study investigates the role of hedging and portfolio design among stocks, exchange rates, and gold in small open economies (SOEs) from 4 January 2000 to 31 March 2020. We adopt the trivariate dynamic conditional correlation-fractionally integrated asymmetric power ARCH model and unconditional quantile regression model, and our findings show that the hedging role of the U.S. dollar (USD) and gold against stocks differs under regular and extreme market conditions. The USD can act as a powerful hedge asset for stocks in regular market periods. Moreover, during the global financial crisis and COVID-19 outbreak, the safe-haven effect of gold becomes stronger for almost all stocks, whereas the USD can serve as a strong safe haven against stock markets of Korea, Taiwan, and Singapore when stock returns are extremely low. In terms of portfolio designing, we find that adding the USD and gold to portfolios improves their hedging effectiveness, and the optimally weighted stock-USD-gold portfolio is the best portfolio strategy, irrespective of referring to return or risk.     

Seemingly inconsistent analyst revisions

In about 20%–30% of cases where an analyst revises two outputs (namely, earnings estimates, target prices, or stock recommendations) simultaneously, the two estimates are revised in opposite directions. Existing literature notes that these inconsistent outputs are widespread, and concludes that they are lower-quality, driven by strategic bias, and are viewed as less valid by investors. We find that these characterizations are generally inaccurate. Apparent inconsistency is largely driven by accounting and economic factors, with only limited evidence that investment banking-related conflicts play a role. Moreover, inconsistent outputs are neither less accurate than consistent outputs nor do they resolve less investor uncertainty upon their release. Overall, our results suggest that researchers should be cautious in interpreting the correlation between analyst outputs as a measure of bias or quality, and in using a single analyst output as a proxy for an analyst's overall views.     

Asset price targeting in an open economy with cognitive limitations: The best for macroeconomic and financial stability?

The choices of policy targets and the formation of agent expectations have been critical issues addressed by monetary policy management since the financial crisis of 2008. This paper evaluates macroeconomic stability in a new Keynesian open economy in which agents experience both cognitive limitations and asset market volatility. The (im)perfect credibility of various monetary policies (e.g., a Taylor-type rule with- or without asset price targeting, strict domestic inflation targeting, strict CPI inflation targeting, and exchange rate peg) may lead agents to react according to their expectation rules, and thus create various degrees of booms and busts in output and inflation. Simulations confirm that a Taylor-type CPI inflation targeting including an asset price target is the best choice. In contrast, the business cycles induced by Keynesian “animal spirits” are enhanced by strict inflation targeting. Furthermore, a credible exchange rate pegging system with an international reserve pooling arrangement can improve social welfare and stability in an open economy, even though its absolute value of the loss function is slightly lower than a Taylor-type CPI inflation targeting including an asset price target.     

房价、房产税、土地财政困境的研究综述与思考

本文回顾了近年来有关房产税在立法基础、对于房价的影响、公平性等问题上的一些讨论成果。首先,房产税立法确有瑕疵,需进一步完善法制体系;其次,沪渝试点房产税设计对于房价的抑制作用有限。