短期生产决策理论下学生党支部最优规模分析

高校学生党支部是高校最重要的基层党组织团队之一。本文利用微观经济学短期生产决策理论,设置支部产出,构建数学模型,利用调查数据进行分析,对高校学生党支部这一特殊团队的规模最优进行了研究。     

Exploiting commodity momentum along the futures curves

This study examines novel momentum strategies in commodities futures markets that incorporate term-structure information. We show that momentum strategies that invest in contracts on the futures curve with the largest expected roll-yield or the strongest momentum earn significantly higher risk-adjusted returns than a traditional momentum strategy, which only invests in the nearest contracts. Moreover, when incorporating conservative transaction costs we observe that our low-turnover momentum strategy more than doubles the net return compared to a traditional momentum strategy.     

Assessing effects of federal crop insurance supply on acreage and yield of specialty crops

Crop insurance may affect harvested acreage and yield by influencing producers’ behavior such as land allocation and input use. Although specialty crops are a major source of farm income, especially on the U.S. west coast, they have not received as much attention as field crops in previous empirical studies. This paper assesses the effect of moral hazard and adverse selection associated with the federal crop insurance program (FCIP) on the acreage and yield of major specialty crops in California. An econometric method that expands the switching regression model is developed to assess the effect. Results suggest that federal crop insurance can change specialty crop growers’ production responses to climate and soil conditions. The moral hazard effect tends to increase the acreage and yield of the specialty crops, whereas the adverse selection effect tends to have the opposite effect. The overall effect of the FCIP on acreage and yield of specialty crops is found to be moderate.     

四川省水稻产投特征变迁及技术进步对单产的影响

[目的]了解四川水稻产投特征和技术进步对单产的影响,促进水稻可持续生产。[方法]分析了改革开放以来四川省水稻产投特征和技术特征变动,并基于索洛余值法测算了1980~2015年四川省科技进步对水稻单产的贡献情况。[结果](1)全省水稻单产水平及物质与服务费用投入均呈现波动增长趋势,人工投入逐年递减,但人工成本在生产成本中的比重较大;(2)四川省水稻品种选育、栽培管理技术、推广技术、稻作经营方式和农业政策不断变迁,更适应当前以普通家庭生产和新型经营主体共同发展的局面对技术的需求;(3)整体来看,近36年技术进步对四川省水稻单产水平提高的贡献率较低,生产经营较为粗放;(4)分时期看,2005年前,技术进步对全省水稻单产水平提高的贡献率较高,但之后尤其是近5年,技术进步并未对水稻单产水平提高产生影响,要素投入是水稻单产水平提升的主要因素。[结论]提出了加强科技研发及投入水平、"一主多元"联合推广、生产管理技术培训和丘区节本增效生产的政策建议。     

Money,Asset Prices,and the Liquidity Premium

This paper examines the effect of monetary policy on the market value of the liquidity services that financial assets provide, known as the liquidity premium. The theory predicts that money supply and nominal interest rates have positive effects on the liquidity premium, but asset supply has a negative effect. The empirical analysis with U.S. data confirms the theoretical predictions. The theory also proposes that the liquidity properties of assets can cause negative nominal yields when the money holding cost is low and liquid assets are scarce. The suggestive empirical findings in Switzerland to support this theoretical result are presented.     

Determinants of yield spread dynamics: Euro versus US dollar corporate bonds

This paper presents a systematic comparison between the determinants of euro and US dollar yield spread dynamics. The results show that US dollar yield spreads are significantly more affected by changes in the level and the slope of the default-free term structure and the stock market return and volatility. Surprisingly, euro yield spreads are strongly affected by the US (and not the euro) level and slope. This confirms the dominance of US interest rates in the corporate bond markets. Interestingly, I find that liquidity risk is higher for US dollar corporate bonds than euro corporate bonds. For both regions, the effect of changes in the bid-ask spread is mainly significant during periods of high liquidity risk. Finally, the results indicate that the credit cycle as measured by the region-specific default probability significantly increases US yield spreads. This is not the case for euro yield spreads.     

Does the bond‐stock earnings yield differential model predict equity market corrections better than high P/E models?

We extend the literature on crash prediction models in three main ways. First, we explicitly relate crash prediction measures and asset pricing models. Second, we present a statistical significance test for crash prediction models. Finally, we propose a definition and a measure of robustness for these models. We apply our statistical test and measure the robustness of selected model specifications of the Price‐Earnings (P/E) ratio and Bond Stock Earning Yield Differential (BSEYD) measures. This analysis shows that the BSEYD and P/E ratios, were statistically significant robust predictors of corrections on the US equity market over the period 1964 to 2014.     

Factor pricing in commodity futures and the role of liquidity

This paper empirically investigates the pricing factors and their associated risk premiums of commodity futures. Existing pricing factors in equity and bond markets, including market premium and term structure, are tested in commodity futures markets. Hedging pressure in commodity futures markets and momentum effects is also considered. This study combines these factors to discuss their importance in explaining commodity future returns, while the literature has studied these factors separately. One of the important pricing factors in equity and bond markets is liquidity, but its role as a pricing factor in commodity futures markets has not yet been studied. To our knowledge, this research is the first to study liquidity as a pricing factor in commodity futures. The risk premiums of two momentum factors and speculators’ hedging pressure range from 2% to 3% per month and are greater than the risk premiums of roll yield (0.8%) and liquidity (0.5%). The result of a significant liquidity premium suggests that liquidity is priced in commodity futures.     

The Politics of Sovereign Credit Spreads

Using a large sample of 35 developing countries for the period 1993–2009, we provide strong and robust evidence that the political institutions in place play a significant role in explaining sovereign spreads. In particular, we find that unconstrained presidential systems increase spreads, while political stability and higher competition for political contest decrease spreads. In addition, political cohesion (political fragmentation) depresses (increases) spreads. Instead, the latter are insignificantly related to political orientation.