广东省县域农业生产效率分析——基于2015-2019年揭阳市5县域DEA模型为例

农业生产效率提升是实现农业现代化的重要手段。本文以《揭阳市统计年鉴(2015-2019)》的农业相关数据,从县域的视角研究揭阳市农业生产效率,运用DEA模型对揭阳市5个县域的3个投入指标和1个产出指标进行实证分析。结果显示,2015-2019年揭阳市农业生产效率均属于DEA无效,总体效率提升并不明显,且各县域呈现发展不平衡的状态,仅惠来县位于生产前沿面上,普宁市的农业生产效率最低,规模报酬属于递减态势。因此,恰逢“十四五”谋划之时,对揭阳市各县域农业生产效率做出分析研究,为现阶段提升揭阳市农业生产效率提出有参考价值的建议,为广东省县域农业生产效率分析提供范本。     

Error analysis of finite difference and Markov chain approximations for option pricing

Mijatovi? and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.     

The aesthetic fidelity effect

Product aesthetics is a powerful means for achieving competitive advantage. Yet most studies to date have focused on the role of aesthetics in shaping pre-purchase preferences and have failed to consider how product aesthetics affects post-purchase processes and consumers' usage behavior. This research focuses on the relationship between aesthetics and usage behavior in the context of durable products. Studies 1A to 1C provide evidence of a positive effect of product aesthetics on usage intensity using market data from the car and the fashion industries. Study 2 corroborates these findings and shows that the more intensive use of highly aesthetic products may lead to the acquisition of product-specific usage skills that form the basis for a cognitive lock-in. Hence, consumers are less likely to switch away from products with appealing designs, an effect that is labeled as the ‘aesthetic fidelity’ effect. Study 3 addresses an alternative explanation for the ‘aesthetic fidelity effect’ based on mood and motivation but finds that the ‘aesthetic fidelity’ effect is indeed determined by usage intensity. Finally, Study 4 identifies a boundary condition of the positive effect of product aesthetics on product usage, showing that it is limited to durable products. In sum, this research demonstrates that the effects of product aesthetics extend beyond the pre-consumption stage and have an enduring impact on people's consumption experiences.     

Unemployment insurance benefits and income smoothing

Labor unemployment insurance reduces unemployment concerns. We argue that these benefits moderate incentives to smooth earnings to reduce employees’ concerns about unemployment risk. Using exogenous variations in unemployment insurance benefits, we find evidence consistent with this argument. We also find that the link between unemployment insurance benefits and income smoothing is stronger when there is higher unemployment risk and when the firm is likely to employ more low-wage workers, who find unemployment insurance benefits especially useful. Our paper contributes to the literature by showing that public policy decisions such as unemployment insurance have significant, albeit probably unintended, externalities on corporate financial reporting.     

中国家庭股市资产价值变动对居民消费的影响——来自CHFS的微观证据

近年来针对股市资产价值变动与消费关系的研究多采用宏观数据，难以揭示股市资产价值变动对居民消费影响的细节。为克服以上缺陷，文章利用中国家庭金融调查（CHFS）数据分析股市资产价值变动对中国居民消费的影响。实证结果表明：（1）股市资产价值变动对居民消费的影响总体较弱，其中市值变动的财富效应主要体现在改善性消费上，而对饮食等日常必须消费和奢侈品消费影响较小，这可能与我国居民的收入结构和投资方式有关；（2）随着年龄增长，居民的收入分布和资产配置倾向发生改变，股市资产价值变动对不同年龄居民消费的影响呈现先减小后增大的U型分布。研究结论揭示了股市资产价值变动对居民消费影响的分布特征，为今后股市改革方向提供了建议。     

Forecasting GDP growth with NIPA aggregates: In search of core GDP

In addition to GDP, which is measured using expenditure data, the U.S. national income and product accounts (NIPAs) provide a variety of measures of economic activity, including gross domestic income and other aggregates that exclude one or more of the components that make up GDP. Similarly to the way in which economists have attempted to use core inflation—which excludes volatile energy and food prices—to predict headline inflation, the omission of GDP components may be useful in extracting a signal as to where GDP is going. We investigate the extent to which these NIPA aggregates constitute “core GDP.” In an out-of-sample forecasting exercise using a novel real-time dataset of NIPA aggregates, we find that consumption growth and the growth of GDP excluding inventories and trade have historically outperformed a canonical univariate benchmark for forecasting GDP growth, suggesting that these are promising measures of core GDP growth.     

Consumption,welfare, and stochastic population dynamics when technology shocks are (Un)tied

The impact of uncertainty on consumption and welfare seems obvious; because of the precautionary saving motive, higher uncertainty reduces consumption, and subsequently, deteriorates welfare. Recent several studies, however, find that this intuitive narrative is not necessarily true. This paper provides the analytical underpinnings for this. In the absence of technological progress, I find that the larger demographic shocks always reduce consumption, but improve the welfare of households. Moreover, when demographic shocks are negatively tied to technology shocks, there emerges an inverted-U relationship between the size of two shocks and consumption, and a U-shaped relationship between the size of two shocks and household welfare. These results are all characterized analytically in the framework of the stochastic two-sector growth model featuring the correlated Brownian motion process. The findings suggest that demographic policies should not be implemented with no reference to the state of technology.     

Monetary policy and food inflation in South Africa: A quantile regression analysis

Although optimal monetary policy stabilizes food inflation theoretically, empirical studies remain limited not only in the context of volumes and the estimation approaches, but are focused on selected advanced and emerging countries to the neglect of Africa where poverty and dominance of food in the consumption basket are more pronounced. We provide empirical evidence in the context of South Africa using quantile regressions. Rising food prices are destabilized even further by restrictive monetary policy; a finding that has ramifications for inflation targeting, especially given that a quarter of the country’s population is food poor.     

新冠肺炎疫情对居民消费的影响及对策

2020年春节期间,湖北省武汉市爆发的由新型冠状病毒感染引起的肺炎疫情正在对中国经济和消费带来负向冲击。从逻辑上看,除了直接限制消费外,疫情还会通过收入效应、财富效应、实际购买力效应对消费形成不利影响。从历史上看,十七年前的"非典"疫情对经济和消费的影响是短期的,但此次疫情影响更大,持续期存在不确定性。稳定消费的关键是稳定居民收入,要稳定居民收入就需要稳定非农产业就业。基于分析,本文提出了一揽子政策建议。     

Comparative performances of measures of consumer and economic sentiment in forecasting consumption: a multi-country analysis

ABSTRACT

This paper seeks to compare the capabilities of assorted measures of consumer and economic sentiment in predicting the growth of household expenditure. An analysis of quarterly data on five European countries shows that for none of these can the model which incorporates the EU’s headline consumer confidence indicator be deemed to be significantly inferior to any of its seven rivals. However, the rankings of the sentiment variables are seen to be influenced by: the proportion of total spending by households that is devoted to durable goods; and the nature of the behaviour of consumption over the forecast interval.