Endogenous fertility and growth in a model with old age support

Summary. This paper examines the interrelationship between capital accumulation, fertility, and growth by introducing an endogenous fertility decision into Diamond's (1965) neoclassical growth model. Under the assumptions that children provide old age support and that individuals incur a variable time cost of raising children, it investigates the potential for cyclical fluctuations in the capital-labor ratio and fertility, as well as for development trap phenomena to be observed. It is shown that when capital and labor are highly substitutable in production, there is a unique steady state equilibrium, and either damped or undamped oscillations in fertility and the capital-labor ratio may occur. However, when the elasticity of substitution between capital and labor is less than one, two steady state equilibria may exist; one with a high capital-labor ratio and a high rate of population growth, and the other with a lower capital-labor ratio as well as a lower population growth rate. The former is a saddle, while the latter may be either a source or a sink. In the latter case development traps are possible. Received: June 16, 1997; revised version: December 18, 1997     

Pensions with endogenous and stochastic fertility

This paper studies the design of a pay-as-you-go social security system in an overlapping generations model where fertility is in part stochastic and in part determined through capital investment. If investments are publicly observable, pension benefits must be linked positively to the level of investment, and payroll taxes negatively to the number of children. The outcome is characterized by full insurance with all parents, regardless of their number of children, enjoying identical consumption levels. Without observability, benefits must increase, and payroll taxes decrease, with the number of children. The second-best level of investment, and the resulting average fertility rate, are less than their corresponding first-best levels.     

Social security and endogenous fertility: pensions and child allowances as siamese twins

This paper analyses public pensions and child support in a model with endogenous fertility. We show that the individual fertility choice may not coincide with the social optimum, due to the existence of external effects of children on society as a whole. The market outcome without government intervention is efficient, however, as the externalities exactly cancel out in that case. If the government wants to redistribute towards the old, it cannot replicate the command optimum by merely applying lump-sum transfers, but rather needs a child allowance scheme to effectively alter the number of offspring. Finally, we analyse whether a Pareto-improving social security reform is possible. It is shown that merely reducing the PAYG-scheme cannot be Pareto-improving, but the introduction of a child allowance scheme can be.     

Endogenous order and information aggregation

Privately informed experts with heterogeneous expertise decide when to give advice and what advice to give. Each expert’s utility depends upon that expert’s own message as well as those of the other experts. Under different forms of payoff externalities, we find varying results for the optimal order in which messages are sent and the existence of herd behavior. Under negative payoff externalities, all experts send a message together without any delay and a herd never arises. This leads to truthful revealing of all private information. Without forcing any order of speech, we obtain a result similar to the ‘anti-seniority rule’. This, however, goes in the opposite direction when positive payoff externalities are induced. An incentive structure with positive payoff externalities gives rise to a herd led by the most precise expert with a delay in the disclosure of information. Next, we test for the nature of payoff externalities in the remuneration of forecasters listed with I/B/E/S. We find that the underlying payoff externalities are negative, i.e. the benefit from making dissimilar forecasts is higher than that from making similar ones.     

On Efficient Child Making

This paper is devoted to the study of the Pareto-efficiency of the competitive equilibrium for an overlapping generations economy with endogenous fertility. Pareto-efficiency needs a reformulation when fertility is endogenous. Then it is proved that a competitive equilibrium that converges in over-accumulation is non-Pareto-efficient. However, we provide an example in which a competitive equilibrium that converges in under-accumulation is non-Pareto-efficient. Finally, we give a general condition that ensures the Pareto-efficiency of the competitive equilibrium. This paper was presented at the conference “Irregular Growth”: Beyond Balanced Growth” , Paris, June 2003. The current version of this paper was completed after Philippe Michel’s sudden death. Bertrand Wigniolle wants to express his deep sorrow for the loss of a close friend and an excellent economist, from whom he learned a lot over the years. The authors would like to thank Tapan Mitra for helpful comments. They also are grateful to Claire Loupias, who began to think with them on the subject and to an anonymous referee for useful suggestions and improvements.     

Endogenous fertility, international migration and growth

An endogenous growth model with heterogeneous agents and endogenous rates of fertility is developed to study the relationships between population growth, human capital, migration and economic development. A variety of patterns of migration, from the migration of the unskilled to the brain drain is considered, where the decision to migrate reflects the agents’ optimising behaviour. The analysis yields implications which accord with the empirical evidence on the relationships between demography and development. Macroeconomic policy can foster growth by influencing labour mobility through taxation and the provision of public goods such as social infrastructure, sanitation, environmental control and medical research that affect locational preferences and child quality. The author is grateful for the comments of an anonymous referee on an earlier version of the paper. The usual disclaimer applies.     

Endogenous innovations in the pharmaceutical industry

This paper addresses the creation of new products in the US pharmaceutical sector, during the second half of the 20th century. We indicate that the continuous increases in population, and thus in the market size of this sector, play a fundamental role in explaining the large creation of new drugs during that period. We also argue that population and market size can be endogenously determined through the impact of drugs over the mortality rate. Hence, these two effects reinforce each other, producing decrements in the mortality rate and increments in the stock of drugs over time. We obtained the set of new molecular entities approved by the FDA during the second half of the 20th century and we decomposed the data in a panel of 15 therapeutic categories over time. Using this data, we tested our hypotheses using different econometric methods. The results support the hypothesis and are consistent across methods.

Endogenous Fertility, Income Distribution, and Growth

This article analyzes the interaction between growth and fertility via income distribution in a model in which fertility decisions are motivated by old-age support. It provides an explanation of the demographic transition of an economy from a stage of increasing fertility and low growth to a stage of low fertility, high human capital investments, and high growth.     

Endogenous time preference and optimal growth

We adapt the classic one-sector optimal growth model to include an endogenous rate of time preference along the lines of Becker and Mulligan (1997). The resulting model is both time-consistent and analytically tractable. Capital sequences are shown to be globally monotone and stable under very general circumstances using lattice programming techniques and value orders. We analyze a series of examples that exhibit a variety of behaviors, including closed-form solutions, unique steady-states, multiple steady-states, and conditionally sustained growth. The endogenous rate of discount preserves monotonicity and stability while allowing for the possibility of non-global convergence.I would like to thank Robert Becker, Leonard Mirman, Michael Kaganovich, Itzhak Zilcha, and an anonymous referee for helpful comments and discussions.     

Does demographic change matter for growth?

How important is the demographic transition for economic growth? To answer this question, this paper constructs a general equilibrium overlapping generations model with endogenous fertility. The model is calibrated to data from Taiwan, a country that experienced rapid economic growth while undergoing significant demographic transition. Our results suggest that more than one-third of the output growth in Taiwan during the past four decades can be attributed to demographic transition, while TFP growth explains another third and the remainder is mainly due to skill-biased technological progress. Our results show that demographic change is an important driver of the growth process in countries undergoing rapid fertility decline.     

Endogenous mortality, human capital and economic growth

We consider growth and welfare effects of lifetime-uncertainty in an economy with human capital-led endogenous growth. We argue that lifetime uncertainty reduces private incentives to invest in both physical and human capital. Using an overlapping generations framework with finite-lived households we analyze the relevance of government expenditure on health and education to counter such growth-reducing forces. We focus on three different models that differ with respect to the mode of financing of education: (i) both private and public spending, (ii) only public spending, and (iii) only private spending. Results show that models (i) and (iii) outperform model (ii) with respect to long-term growth rates of per capita income, welfare levels and other important macroeconomic indicators. Theoretical predictions of model rankings for these macroeconomic indicators are also supported by observed stylized facts.     

内生增长框架下的中小企业和我国经济增长稳定

稳定中国经济高速增长的措施除了扩大国内需求之外,还可以从供给的角度考虑中小企业的作用。中小企业在国民经济总量中的重大贡献和中小企业内部管理不足的矛盾是影响我国经济增长趋于不稳定的一个重要因素。理论和实证分析结果表明,企业家知识溢出能力是决定企业私人知识边际产出的重要因素,中小企业主缺乏企业家的知识溢出能力是导致人均产出份额低于总量产出份额的主要原因。本文结论是我国要加大中小企业内部管理投入,促进中小企业主向企业家的实质性转变,提高中小企业主的知识产出能力,用以提高中小企业资源的使用效率,从而提高我国要素的整体使用效率,最终为稳定我国高速经济增长提供一个长远动力。     

Endogenous technological change with leisure-dependent utility

Summary. This paper investigates the effect of introducing leisure-dependent utility into two models of endogenous technological change. Due to the flexibility in the labour supply the dynamics of the models change significantly. It is shown that if agents attach enough value to leisure in comparison to consumption two balanced growth paths may exist. This implies that economies with the same preferences and the same technology may experience different long-run growth rates. Received: October 17, 1997; revised version: January 6, 1999     

Fertility,income and welfare in an OLG model with regulated wages

We analyse the effects of the regulation of wages in a standard one-sector OLG model of neoclassical growth extended to account for endogenous fertility decisions of households and unemployment benefit policies financed at balanced budget. In contrast with the prevailing literature, which has failed to pay due attention to inter-temporal contexts, our conclusion is that minimum wages may be introduced not only for equity reasons, that is, to increase the income of low-paid workers, but under suitable conditions—i.e., if production is sufficiently capital oriented and the unemployment benefits are high enough—minimum wage legislation might be considered as a source of increased economic performance despite unemployment, i.e. a regulated-wage economy performs better than a market-wage economy. As a consequence, since higher minimum wages raise per capita income together with increasing unemployment, our results imply that a positive correlation between unemployment and long-run income per-capita may exist. Further, the lifetime welfare of the representative generation may be increased as well. Finally, the wage rate may also be treated as a policy instrument for the control of population growth.

内生增长、政府生产性支出与中国居民消费

中国财政支出的较大一部分用于生产建设,中国居民消费与政府生产性支出表现出稳健的正相关关系,这一事实与从标准的新古典和新凯恩斯模型得出的挤出效应截然不同。本文构建了包含存量和流量两部分政府生产性支出的内生增长模型,研究表明,政府支出增加在提高税负、挤出居民消费的同时,也通过其生产性增加收入、挤入居民消费;政府支出增加究竟挤入还是挤出居民消费取决于两种效应的比较以及政府的生产性支出比重和税负水平。政府生产性支出的最优结构等于其相对生产性之比,政府支出的最优规模等于政府支出的生产性。     

Minimal belief change, Pareto-optimality and logical consequence

Summary. A rational agent changes her beliefs in response to new information; a widely held idea is that such belief changes should be minimal. This paper is an overview of the theory of minimal belief revision. I employ a decision-theoretic framework to compare various principles for minimal belief revision. The main topics covered include the AGM postulates for belief revision, belief contraction, Grove's representation theorem, axioms for conditionals, and the connections between minimal belief change and questions in formal logic. I characterize under what conditions belief revision functions are consistent with the Levi Identity, and under what conditions belief contraction functions are consistent with the Harper Identity. Received: August 20, 2000; revised version: March 19, 2001     

Endogenous fertility,Ricardian equivalence,and debt management policy

This paper develops a model in which dynastic families optimally determine fertility. Government debt represents a tax on future generations and on childbearing; the Ricardian Equivalence Hypothesis does not hold. Debt is welfare reducing in that it distorts the fertility decision. An increase in government debt induces a decline in fertility and an increase in the steady state capital/labor ratio. If a government inherits an existing stock of debt, the 1st-best policy is to eliminate the debt immediately. In other situations the optimal debt management policy will not, in general, entail a total elimination of the debt.     

内生时机选择下国有和外资银行的利率竞争

结合中国银行业的背景,本文建立了国有和外资银行以利率为决策变量的 Bertrand 和 Stackelberg 混合寡占模型,并以内生时机选择为思路,前瞻性地探讨了国有和外资银行的竞争格局和时机选择问题.研究发现:(1)在一定参数范围内,国有银行较外资银行有更低的存款利率.在国有化程度较小时,Bertrand下的国有银行利润大于其作为领导者的利润;(2)在国有银行做领导者的利率竞争中,国有和外资银行存款利率会随着国有化程度及二者存款收益的增加而上升;(3)在私有化程度很高且二者存款收益相等时,利率竞争扩展博弈的SPNE是国有银行领先,外资银行跟随.     

工业与农业相互依存的内生增长模型——工业反哺农业的理论基础

通过吸收内生增长理论的思想,将两部门的技术进步同时内生化,本文提出了一个工业和农业相互依存的二元经济内生增长模型,并以此对目前争议颇多的"工业反哺农业"的时机和政策问题,从二元经济结构转换的角度进行了分析.本文认为,通过促进农村劳动力向工业部门转移可以推动中国经济的持续增长,加大对农业的投入和加快资本积累是推动农村劳动力转移、实现二元经济结构转换和经济持续增长的关键,因此工业反哺农业是我国经济均衡发展的必要条件.     

可再生资源约束下的内生增长模型研究

关于可持续发展,新经济增长理论主要关注耗竭性资源与环境问题对长期经济增长的影响。通过假设技术进步取决于研发投入,本文建立了一个包含可再生资源的内生增长模型,采用最优控制理论得到了模型的稳态增长解,并得出结论:可持续增长不能单方面强调技术进步,对可再生资源的合理利用也是实现可持续增长的有效途径。