Product and country substitution in imports: An empirical comparison of theoretical concepts

Product and Country Substitution in Imports: An Empirical Comparison of Theoretical Concepts. — The paper focuses on the shortcomings of current unit-values based measures for estimating product and country substitution in imports. The results of the bilateral index number technique in measuring changes in the country composition or product mix of imports were found to be inadequate, which was shown in an analysis of data on the French import market for chairs. An improved technique is briefly summarized, and its applicability compared with the bilateral index number technique. The new method performed accurately and provided a reliable basis for a refined analysis of changes within import markets.     

220KV线路微机保护器的运行与维护

随着220KV微机线路保护的广泛应用,微机线路保护的一些缺陷也开始逐渐显现出来。本文针对微机线路经常出现的一些故障和缺陷,提出了在220kv微机保护运行管理中要注意的一些问题。     

An extremely simple proof of the K-K-M-S Theorem

Summary.  An extremely simple proof of the K-K-M-S Theorem is given involving only Brouwer’s fixed point theorem and some elementary calculus. A function is explicitly given such that a fixed point of it yields an intersection point of a balanced collection of sets together with balancing weights. Moreover, any intersection point of a balanced collection of sets together with balancing weights corresponds to a fixed point of the function. Furthermore, the proof can be used to show -balanced versions of the K-K-M-S Theorem, with -balancedness as introduced in Billera (1970). The proof makes clear that the conditions made with respect to by Billera can be even weakened. Received: January 22, 1996; revised version June 9, 1996     

Non-addictive habits: optimal consumption-portfolio policies

We formulate a model of preferences with non-addictive habits, where consumption is required to be non-negative at all times, but can fall below a “standard of living” index that aggregates past consumption. We study the consumption-portfolio problem taking account of the non-negativity constraint on consumption, and provide a constructive proof for the existence of an optimal policy on a finite time-horizon [0,T]. We show that the consumption constraint binds up to an endogenous stopping time τ∗∈[0,T], after which it remains slack until T. A decomposition of constrained consumption involving an Asian average-strike capped call-option is demonstrated.     

Exit problems in regime-switching models

This paper provides a general framework for pricing of perpetual American and real options in regime-switching Lévy models. In each state of the Markov chain, which determines switches from one Lévy process to another, the payoff stream is a monotone function of the Lévy process labeled by the state. This allows for additional switching within each state of the Markov chain (payoffs can be different in different regions of the real line). The pricing procedure is efficient even if the number of states is large provided the transition rates are not very large w.r.t. the riskless rates. The payoffs and riskless rates may depend on a state. Special cases are stochastic volatility models and models with stochastic interest rate; both must be modeled as finite-state Markov chains. As an application, we solve exit problems for a price-taking firm, and study the dependence of the exit threshold on the interest rate uncertainty.     

A Simple Test for Cointegration in Dependent Panels with Structural Breaks*

This paper develops a very simple test for the null hypothesis of no cointegration in panel data. The test is general enough to allow for heteroskedastic and serially correlated errors, unit‐specific time trends, cross‐sectional dependence and unknown structural breaks in both the intercept and slope of the cointegrated regression, which may be located at different dates for different units. The limiting distribution of the test is derived, and is found to be normal and free of nuisance parameters under the null. A small simulation study is also conducted to investigate the small‐sample properties of the test. In our empirical application, we provide new evidence concerning the purchasing power parity hypothesis.     

Anonymous markets and monetary trading

We study infinite-horizon monetary economies characterized by trading frictions that originate from random pairwise meetings, and commitment and enforcement limitations. We prove that introducing occasional trade in ‘centralized markets’ opens the door to an informal enforcement scheme that sustains a non-monetary efficient allocation. All is required is that trading partners be patient and their actions be observable. We then present a matching environment in which trade may occur in large markets and yet agents’ trading paths cross at most once. This allows the construction of models in which infinitely lived agents trade in competitive markets where money plays an essential role.     

Land inequality and economic growth: a dynamic panel data approach

The growing body of literature devoted to studying the impact of inequality on economic growth has centered its attention on the income distribution effect, even though the theoretical relationships are more related to assets distribution. While some recent studies have tried to overcome this limitation by introducing asset indicators, they meet new constraints when dealing only with time-invariant measurements for this explanatory variable. This article provides a theoretical discussion and some novel empirical tests to better understand the relationships between assets distribution and economic growth. We assembled a new panel database that includes observations for more than 30 countries over the last three decades. The data include a time-varying variable for changes in the Land Gini index over this period that enables us to overcome the limitations of previous studies. A system general method of moments (GMM) estimator is used to generate truly unbiased and consistent estimates for the parameters of interest. We explore some of the likely channels through which asset distribution and economic growth may be linked, paying particular attention to the role of secure property rights and the relations between land ownership and education. We find robust and significant negative signs for land inequality in the growth regressions, indicating that changes in asset distribution are an important factor for economic development.     

HURDLE MODELS OF ALCOHOL AND TOBACCO EXPENDITURE IN SOUTH AFRICAN HOUSEHOLDS1

Estimates of participation or expenditure elasticities depend upon the assumptions made regarding the observation of zero expenditure at the household level. This research examines two single‐hurdle models across two commodities for which nearly two‐thirds of the observations are zero. The research shows that one hurdle model consistently outperforms the other, and does so for intuitively appealing reasons.     

Multilateral aggregation-theoretic monetary aggregation over heterogeneous countries

We derive fundamental theory for measuring monetary service flows aggregated over countries within a multicountry area. We develop three increasingly restrictive approaches: (1) the heterogeneous agents approach, (2) the multilateral representative agent approach, and (3) the unilateral representative agent approach. These results are being used by the European Central Bank in construction of its Divisia monetary aggregates database, with convergence from the most general to the more restrictive approaches expected as economic convergence within the area proceeds. Our theory permits monitoring the effects of policy over a multicountry area, while also monitoring the distribution effects of policy among the countries.