Optimal savings with taxable and tax-deferred accounts

We solve and estimate a life-cycle model with earnings risk and liquidity constraints in the presence of tax-deferred retirement accounts (TDAs). We explicitly consider two very different types of households (with TDAs): direct and indirect stockholders. The latter hold stocks only through TDAs and, consistent with the data, save considerably less than the former, who hold stocks both inside and outside these accounts. We find that TDAs promote higher wealth accumulation but only marginally higher net savings. Consumption increases mostly during retirement, as desired, but the effect is largest for those households with higher savings rates already.     

No Arbitrage in Discrete Time Under Portfolio Constraints

In frictionless securities markets, the characterization of the no-arbitrage condition by the existence of equivalent martingale measures in discrete time is known as the fundamental theorem of asset pricing. In the presence of convex constraints on the trading strategies, we extend this theorem under a closedness condition and a nondegeneracy assumption. We then provide connections with the superreplication problem solved in Föllmer and Kramkov (1997).     

State prices,liquidity, and default

We show, in a monetary exchange economy, that asset prices in a complete markets general equilibrium are a function of the supply of liquidity by the Central Bank, through its effect on default and interest rates. Two agents trade goods and nominal assets to smooth consumption across periods and future states, in the presence of cash-in-advance financing costs that have effects on real allocations. We show that higher spot interest rates reduce trade and as a result increase state prices. Hence, states of nature with higher interest rates are also states of nature with higher risk-neutral probabilities. This result, which cannot be found in a Lucas-type representative agent model, implies that the yield curve is upward sloping in equilibrium, even when short-term interest rates are fairly stable and the variance of the (macroeconomic) stochastic discount factor is 0. The risk-premium in the term structure is, therefore, a monetary-cost risk premium.     

Form of Ownership and Financial Constraints:Panel Data Evidence From Flow of Funds and Investment Equations

This paper analyzes the effects of the form of ownership on the substitutability between internal and external sources of finance in Italy. In particular, we test whether financial constraints are more severe for independent firms compared to members of large national business groups and subsidiaries of foreign multinational corporations. The results obtained from flow of funds and investment equations estimated for a panel of Italian companies imply that independent firms face more severe financial constraints. In fact, not only members of national groups and subsidiaries of multinational corporations find it easier to substitute cash flow with external finance when the former falls but they do not display excess sensitivity to cash flow and debt in their investment decisions.     

Local martingales, arbitrage, and viability Free snacks and cheap thrills

Summary. We revisit a standard model of security prices as Ito processes, and provide some new economic insights about the role of arbitrage and credit limits within such a model. We show that the standard assumptions of a positive state prices and existence of an equivalent martingale measure exclude prices that are viable models of competitive equilibrium and that are potentially useful for modeling actual financial markets. These models have been dismissed in the past as allowing arbitrage, but in fact an agent who prefers more to less and who has limited access to credit may have an optimum. Received: June 9, 1999; revised version: October 4, 1999     

内部控制影响国有企业竞争优势的中介效应研究

本文以2012—2019年国有上市公司为研究对象,基于公平竞争的市场环境持续改善的背景,实证研究内部控制对国有企业竞争优势的影响及作用机理。本文通过构建多元回归模型检验内部控制对国有企业竞争优势的提升效应,运用中介效应模型验证企业家精神、创新活动、融资约束在内部控制与国有企业竞争优势之间的中介作用。研究发现：内部控制质量与国有企业竞争优势显著正相关;企业家精神、创新活动与融资约束在内部控制对国有企业竞争优势的影响中存在部分中介效应。因此,可以从政府监管层面、制度层面和企业层面通过健全内部控制、激发企业家精神、促进创新活动以及降低融资约束等方式提升国有企业竞争优势。     

融资约束抑或过度投资——中国上市企业投资一现金流敏感度的经验证据

本文以中国上市企业为分析样本，通过检验现金持有量对投资一现金流敏感度的影响，考察企业中的融资约束和代理）中突。结果显示，融资约束与过度投资导致企业投资支出与内部现金流密切相关。民营企业、大规模地方国有企业中存在过度投资，所持有的现金具有明显的壕沟效应、进一步提高投资一现金流敏感度。而中、小规模国有企业面临的融资约束比较突出，为了抵御外部融资约束，持有现金充当对）中工具、降低投资一现金流敏感度。     

金融科技与企业创新——新三板上市公司的证据

金融科技催生出新的金融服务模式,这能否解决实体经济的融资难题从而促进企业创新呢?通过“金融科技”关键词百度新闻高级检索,本文创新性地构建了地区金融科技发展水平指标,并利用2011—2016年新三板上市公司数据,考察了金融科技发展对企业创新的影响及其机制。实证结果表明,金融科技发展显著促进了企业创新。就经济意义而言,城市的金融科技发展水平每提高1%,当地企业专利申请数量平均会增加约0.17项。作为一个宏观变量,地区金融科技发展水平受单个企业创新行为的影响较小,但是依然会存在测量误差和遗漏变量等内生性问题。本文运用接壤城市金融科技发展水平的均值作为工具变量,得到了一致的估计结果。本文的结果在替换企业创新指标、使用不同回归模型等一系列稳健性检验后仍然成立。机制分析表明,金融科技通过两个渠道促进企业创新,一是缓解企业的融资约束,二是提高税收返还的创新效应。异质性分析表明,金融科技促进企业创新的作用在东部地区和高科技行业表现得更为明显。在中国经济高质量发展背景下,持续推进金融科技发展、重塑金融行业生态格局,才能为实体经济提供源源不断的创新活力,从而推动创新型国家建设。     

The Influence of a Credit Rating Change on Dividend and Investment Policy Interactions

We examine firms’ alterations in dividend and investment activities following credit rating changes. We find that downgraded firms reduce both dividends and investments more than no‐rating‐change firms. However, a silver lining of this doubly negative impact for shareholders is an increase in investment efficiency in firms that are most likely to overinvest. For upgraded firms, investments increase, but dividend outlays do not, compared to firms without rating changes. Our findings of asymmetric dividend stickiness and symmetric investment changes on a credit shock suggest that dividends and investments should not always be considered competing uses of funds.     

基于双重约束的区域耕地整理适宜性评价研究

[目的]科学合理的适宜性评价是确保耕地整理能够有效开展的前提条件,同时对于我国的耕地保护与粮食安全保障也具有极为重要的意义。[方法]该研究首先选取可以反映区域耕地整理适宜性的指标因子,然后参考胡学东提出的约束条件评价模型,引入区域生态安全和社会经济双重约束,对研究区域在双重约束下的耕地整理适宜性进行评价,并通过K-Means聚类法将研究区域的耕地整理适宜性分区进行合理划分。[结果]生态安全约束和社会经济约束对区域耕地整理适宜性水平具有重大影响,高生态安全约束与高社会经济约束会降低耕地整理的适宜性,低生态安全约束与低社会经济约束会提高耕地整理的适宜性。[结论]引入生态安全约束和社会经济约束后,可以在一定程度上反映山地区域在社会经济与生态安全双重约束状态下的耕地整理适宜性情况,耕地整理适宜性评价结果更加符合当地实际情况,约束条件评价模型可以更加合理准确地对处于约束条件下的耕地整理适宜性进行评价,是对耕地整理适宜性评价方法的丰富与完善。