Optimal fertility along the life cycle

We explore the optimal fertility timing in a four-period OLG economy with physical capital, whose specificity is to include not one, but two reproduction periods. It is shown that, for a given total fertility rate, the economy exhibits quite different dynamics, depending on the timing of births. If all births take place in the late reproduction period, there exists no stable stationary equilibrium and the economy exhibits cyclical dynamics due to labor growth fluctuations. We characterize the long-run social optimum and show that optimal consumptions and capital depend on the optimal cohort growth factor, so that there is no one-to-one substitutability between early and late fertility. We also extend Samuelson’s Serendipity Theorem to our economy and study the robustness of our results to: (1) endogenizing fertility timing, (2) assuming rational anticipations about factor prices, (3) adding a third reproduction period.     

论城管行政执法体系的构建

我国各地的城管部门虽然有着同一称谓,但是其职责范围却不尽相同。在城管执法人员的编制上,有的是机关编制,有的是事业编制,有的是合同工,在执法的主体资格上也存在很大差异。目前我国还没有统一的相关城管执法立法,城管在执法过程中常常面临职责不清的情况。在执法过程中,执行难的问题时常发生。所以有必要对于城管执法问题进行研究,构建符合我国国情的城管执法体系,厘清城管执法与其他行政部门之间的责任范围,解决好城管执法过程中存在的相关法律问题。     

Intraday data and hedging efficiency in interest spread trading

Three government bond futures contracts and their respective 3-month interest rate futures contracts traded on LIFFE are examined. The data period covers three years of observations, January 1994-December 1996, sampled at half-hourly intervals. Borrowing from the calculation of minimum variance hedge ratios, half-hourly minimum variance spread ratios (the ratio of one contract to another, which provides the minimum variance) are estimated for the above contracts. The hypothesis under examination is whether there is any value-added in estimating minimum spread ratios based on intraday data. Three spread ratios are defined: two ratios calculated from daily data and a third one based on intraday data. Evidence tends to indicate that spread ratios calculated from intraday data exhibit a substantially lower variance than the other two spread ratio speciications. Thus, it is shown that intraday data, in comparison with daily data, allow for lower hedging costs. Moreover, the use of intraday-based spread ratios might be a contributing factor to reducing the maximum cumulative loss potentially incurred while holding a spread position.     

A new look at the forward premium “puzzle”

We decompose the spot and forward rates into (permanent) nonlinear trend components and (transitory) stationary components. We examine the unbiasedness of the permanent (transitory) component of the forward rate in predicting the permanent (transitory) component of its corresponding future spot rate. The transitory component of the future spot rate under reacts to the transitory component of the forward rate. However, the permanent component of the forward rate is an unbiased predictor of the permanent component of the future spot rate. A robust nonlinear cotrending relation is also found between the forward and future spot rates and the hypothesis of the forward‐rate unbiasedness is sustained in the long run. These results suggest that the forward rate better explains the long‐term behavior of the future spot rate. Simulation analysis shows that if the transitory component of the forward rate fully predicts the transitory component of the future spot rate, the forward premium puzzle disappears. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 31:599–628, 2011     

On the Deadweight Cost of Production Requirements for Geographically Differentiated Agricultural Products

This article investigates the welfare effects of alternate producer collusion schemes in a context where collusion is authorized in order to cover fixed costs. Using a linear equilibrium displacement model, we find evidence that, when the producer group is allowed to control quota levels, an input quota policy entails a smaller absolute deadweight loss than an output quota policy. This finding suggests that if producer groups are allowed to resort to production-distorting instruments to limit output, they will make production choices that are less costly for society than if they had been allowed to directly control output levels.     

Fiscal Policy when Individuals Differ with Regard to Altruism and Labor Supply

This paper studies the incidence of tax-transfer policy in a growth model wherein individuals differ according to their level of intergenerational altruism and have an endogenous labor supply. The main result is that public debt is neutral at the macro level but redistributes resources from nonaltruists to altruists. Capital income taxation can hurt the nonaltruists who do not have any wealth more than it hurts the altruists who own all of it. Whether or not the altruists supply a positive amount of labor makes a big difference as to the incidence of alternative tax transfer policies.     

What Can Acreage Allocations Say about Crop Supply Elasticities? A Convex Programming Approach to Supply Response Disaggregation

This article has two goals. The first is to extend previous results regarding calibration of land‐constrained programming models of agricultural supply against supply elasticities to the general case of multiple constraints. The second goal is to demonstrate how the resulting calibration conditions can be used as a source of identification to disaggregate crop supply elasticities down to the level at which static information on acreage allocations is available. We propose an information‐based disaggregation algorithm to systematically generate regionalised elasticities from a single prior, and provide an empirical illustration.