Technology adoption and accumulation in a vintage-capital model

We present a model of capital accumulation and technology adoption in a vintage-capital framework. The model is an infinite-horizon/infinite-dimensional optimal control model: the firm employs a continuum of technologies (a continuum of heterogeneous capital goods). Capital goods are technology specific, their technology is related to vintage and technology progress. The entrepreneur maximizes the profits obtained by employing a continuum of technologies under the assumption of constant returns to scale and bearing adjustment costs for gross investments. The diffusion of a new technology is established by allowing the entrepreneur to invest in vintage capital goods.     

Human capital investment and debt constraints

When young individuals face binding debt constraints, their human capital investments will be insufficiently financed by private creditors. If generations overlap, then a well-designed fiscal policy may be able to improve human capital investments by replacing missing capital markets with an intergenerational transfer scheme. The optimal (balanced budget) fiscal policy in this context entails the joint provision of an education subsidy for the young and a pension program for the old, financed with a tax on those in their peak earning years. We demonstrate, however, that the desirability of such a cradle-to-grave policy depends crucially on the assumption of an exogenous debt constraint. If debt constraints arise endogenously for reasons of limited commitment, then the optimal (balanced budget) fiscal policy looks radically different. Furthermore, we find that cradle-to-grave type policy interventions may actually lead to lower levels of human capital investment as altered default incentives induce private creditors to contract the supply of student loans by an amount greater than the subsidy. In some cases, the constrained-optimal policy entails zero intervention. These results highlight the importance of taking seriously the reasons for why debt constraints exist.     

Diffusion and directed technological knowledge,human capital and wages

By connecting the North–South diffusion and the bias of non-scale technological knowledge and by considering endogenous human capital, we relate the technological-knowledge diffusion with levels, inter-country gaps, growth rates, wage-inequality paths and specialisation patterns. Inter-country gaps fall towards the steady state and the South produces more final goods at the end of the adjustment process. Moreover, it exports relatively more final goods of the type that uses more intensively the relatively abundant human capital and imitated intermediate goods. However, outputs, wages and prices remain different and differences in prices originate the intra-country wage-inequality paths observed in developed and developing countries, since the early 1980s.     

Within-family inequalities in human capital accumulation in India

We investigate within-family inequalities in human capital accumulation in India. Indicators of the children's current stock of human capital and of investment into their continued human capital accumulation are analyzed, distinguishing between time investments and pecuniary investment into school quality. We employ a within-family model using sibship fixed effects, and find mostly negative birth order effects; that is, earlier-born children are better off. However, for time investments there is a tendency toward more positive birth order effects, especially in poor and large families. This suggests that that opportunity cost of child time matters; in poor and large families the older, more productive, siblings often need to work. The most plausible explanation for negative birth order effects in general is resource dilution at an early age. Older siblings were only children at an early age, and therefore benefited from more parental resources.     

Embodiment, productivity, and the age distribution of capital

An important theme in modern research on productivity has been that technological progress may be embodied in capital in the sense that traditional measures of TFP growth reflect unmeasured improvements in the quality of capital inputs as well as pure disembodied technological progress. It is commonly believed that an implication of this embodiment hypothesis is that there should be a negative relationship between measured TFP and the age of the measured capital stock. This paper presents empirical evidence which suggests that an increase in the age of the capital stock is actually associated with higher TFP growth. This surprising result may be due to the presence of a mis-measurement normally overlooked in this literature: With mis-measured improvements in capital quality, the usual depreciation rates used to construct empirical capital stocks are incorrect for growth accounting. This effect dominates the usual average age effect.     

Differences in growth with international capital markets and financial innovation

This paper presents a model in which technological progress affects the productivity of the financial sector. When technological progress moves quicky, the financial intermediation costs are low, which increases the incentives to invest in new technology. This feedback process involves two types of long-run equilibria: one with low financial intermediation costs and high growth, and the other with high financial intermediation costs and low growth. These divergences in growth rates among countries hold even in the presence of international capital markets with free capital mobility, a very unusual result in the endogenous growth literature.     

On representative social capital

This paper analyzes the behavior of subjects randomly drawn from the Dutch population who reveal their capacity to provide and sustain social capital by their propensity to invest and reward investments in an economic experiment. We find that heterogeneity in behavior is characterized by several asymmetries—men, the young and elderly, and low educated individuals invest relatively less, but reward significantly more investments. The age effects are found to corroborate existing findings, whereas those of gender and education do not. Higher expected levels of investments by others are found to have a positive and significant effect on own investments. Finally, a laboratory experiment with student subjects is found to provide a lower bound of the population level of social capital.     

Endogenous human capital formation,distance to frontier and growth

We examine human capital's contribution to economy-wide technological progress through two channels – imitation and innovation – innovation being more skill-intensive than imitation. We develop a growth model based on the endogenous ability-driven skill acquisition decision of an individual. It is shown that skilled human capital is growth enhancing in the “imitation-innovation” regime and in the “innovation-only” regime whereas unskilled human capital is growth enhancing in the “imitation-only” regime. Steady state exists and, in the long run, the economy converges to the world technology frontier. In the diversified regime, technological progress raises the return to ability and generates an increase in wage inequality between and within groups – consistent with the pattern observed across countries.     

有偏技术进步、要素替代与创新溢出效应——2000—2017年中国工业经验分析

在要素替代框架下，构建一个有偏技术进步的超越对数成本函数模型，利用2000—2017年中国工业面板数据估计有偏技术进步对创新溢出效应的影响。结果发现：资本和能源有偏技术进步对创新溢出存在显著负向效应，劳动有偏技术进步对创新溢出存在显著正向效应，而中间品有偏技术进步对创新溢出的正向效应不显著。进一步将要素替代弹性变量纳入模型后发现，当资本、劳动、能源和中间品替代弹性临界阈值分别高于2.864 0、5.234 1、6.453 2及4.163 9时，有偏技术进步对创新溢出具有显著正向效应。上述发现表明，技术进步遵循具有比较优势的创新资源，本质上有利于提升创新溢出效应。     

Physical and human capital,fertility, and childcare services

We shed light on a nexus between fertility transitions and economic growth patterns. We construct a two-sector overlapping generations (OLG) model with endogenous fertility, physical capital, and human capital, where one sector produces goods, and another produces childcare services. If the elasticity of fertility for expenditure on childcare services is zero, the economy experiences endogenous growth, and fertility does not depend on physical and human capital, but it increases with parental child-rearing time. On the other hand, if elasticity is positive, the economy converges to a steady state, and the number of children becomes the homogenous function of degree of elasticity (less than one). In other words, fertility is the decreasing-return-to-scale function of physical and human capital. We show that a subsidy policy for education is more desirable than a subsidy for childcare services.     

Human capital accumulation in R&D-based growth models

This paper develops a model that reproduces the essential aspects of the recent ICT-based economy using the framework of endogenous growth theory in which a central role is played by human capital accumulation. In particular, it considers a multi-sectoral growth model in discrete time with infinite horizon, endogenous growth, embodied technological progress, horizontal differentiation and “lab-equipment” specification of R&D, and with human capital accumulation (represented by the fact that households devote a fraction of their time to schooling), in order to take into account the crucial role of the latter when new technologies are present. In this model it is possible to obtain some important results, both analytically and through simulations, either in the case of constant productivity of schooling and in the case in which this productivity is a function of technological progress. The first conclusion is that the productivity of schooling affects the long run growth of the economy, contrary to the productivities of the other sectors, hence in this model human capital accumulation is the true engine of growth. It is then possible to study the reaction of the economy to different types of shocks, and to compare the results with the empirical evidence. The conclusion is that the model is able to reproduce such evidence, suggesting that the interaction between ICT and human capital is one of the drivers of the recent economic performance.     

进口结构与技术进步：中国的经验证据

本文针对进口能否产生技术溢出从而促进进口国的技术进步或生产率提高这一问题,首先构造了进口结构指标及技术进步指标,然后对进口结构与技术进步的相互作用进行了协整分析和格兰杰因果关系检验。结果表明:资本品、中间品的进口均对技术进步有长期稳定的促进作用;我国进口存在技术溢出,且中间进口品的技术溢出作用较强,但进口结构与技术进步之间不存在双向因果关系,贸易结构改善与技术进步之间的良性循环并未形成。根据以上结论,本文提出了加强对外贸易、充分利用技术传递,将技术创新与技术传递有机结合,用竞争扶持代替关税保护这三项政策建议。     

Market and public provision in the presence of human capital externalities

For many goods and services, such as health, education, legal services, police protection, the cost incurred by an individual supplier for providing quality is affected by the human capital of her colleagues. The paper shows that this human capital externality is crucial to determine whether such goods and services should be privately or publicly provided. Public and private provisions give individuals different incentives to acquire human capital, and the paper shows that either may be socially preferable, depending on the nature of the human capital externality: private provision of the final goods and services gives stronger incentives to human capital acquisition (and may therefore be socially preferable) if own human capital and one's colleagues' human capital are substitutes, and if suppliers with high human capital benefit more than suppliers with low human capital from their colleagues' human capital, but not excessively so.     

On variable capital utilization and international trade theory

If variable capital utilization results from within-period technological productivity variations, no modification of standard trade theory is required. If it results from within-period factor price variations, the modifications required are those of many factors in variable supply, i.e., non-traded goods.     

Public capital in the 21st century: as productive as ever?

The global financial crisis and the euro area sovereign debt crisis that followed induced a rapid deterioration in the fiscal positions of countries across the globe. In the ensuing fiscal adjustment process, public investments were severely reduced in many countries. How harmful is this for growth perspectives? Our main objective is to find out whether the importance of public capital for long run output growth has changed in recent years. To this end, we expand time series on public capital stocks for 20 OECD countries and estimate country-specific recursive vector autoregressive (VAR) models. Results show that the effect of public capital shocks on economic growth has not increased in general, although results differ widely between countries. This suggests that the current level of public investments generally does not pose an immediate threat to potential output. Of course, this could change if low investment levels are sustained for a long time.     

Welfare Effects of Different Public Expenditures and Taxes in the Netherlands

This paper explores the welfare effects of public consumption, income transfers and public investment financed through different types of taxes. One surprising result is that, contrary to public consumption goods, public capital goods do not necessarily become less attractive if distortionary taxes, rather than lump-sum taxes, are necessary to finance them. The numerical simulations reveal that the net welfare effects of public investments in the Netherlands are typically positive if financed through lump-sum taxes or distortionary taxes on labor. However, if a source-based capital tax is adopted to finance public investments, the overall welfare effect may be negative.     

外商直接投资的知识溢出与中国区域经济增长

本文构建了包括国内知识资本、外商在华直接投资的知识溢出和地区技术进步的分析框架,通过中国29个省(直辖市、自治区)1992—2006年的面板数据检验了中国区域R&D投入、外商在华直接投资的知识溢出对地区技术进步的影响。研究表明:地区自身科技投入是推动地区技术进步的最主要因素;受中国目前引资结构和质量的影响,外商在华直接投资的知识溢出效应特别是通过FDI企业在当地从事生产活动带来的知识溢出效应并不明显;FDI渠道传递的外国R&D资本对技术进步的促进作用与当地的经济、科技发展水平有着密切关系。在上述结论的基础上,论文对中国FDI引资战略和区域经济发展提出了相应的政策建议。     

When do thick venture capital markets foster innovation? An evolutionary analysis

In this paper, we examine the trade off between different effects of the availability of venture capital on the speed of technological progress in an industry. We consider an evolutionary industry simulation model based on Nelson and Winter (1982), in which R&D efforts of an incumbent firm generate technological know-how embodied in key R&D employees, who might use this know-how to found a spinoff of the incumbent. Venture capital is needed to finance a spinoff, so that the expected profits from founding a spinoff depend on how easily venture capital can be acquired. Accordingly, thick venture capital markets might have two opposing effects. First, incentives of firms to invest in R&D might be reduced and, second, if spinoff formation results in technological spillovers between the parent firm and the spinoffs, the generation of spinoff firms might positively influence the future efficiency of the incumbent’s innovation efforts. We study the manner in which this tradeoff influences the effect of venture capital on innovation expenditures, speed of technological change and evolution of industry concentration in several scenarios with different industry characteristics.     

The cost of capital,asset prices,and the effects of monetary policy

The primary objective of this paper is to study the interaction between monetary policy, asset prices, and the cost of capital. In particular, we explore this issue in a setting where individuals face idiosyncratic risk. Incomplete information also provides a transactions role for money so that monetary policy can be studied. In contrast to standard monetary growth models which focus on the transmission of monetary policy to the demand for capital goods, we incorporate a separate capital goods sector so that the supply response to monetary policy is taken into account. Consequently, in contrast to the standard monetary growth model, monetary policy plays an important role in investment activity through the relative price of capital goods. Moreover, different sources of productivity can affect the degree of risk sharing. Although the optimal money growth rate falls in response to an increase in productivity in either sector of the economy, monetary policy should react more aggressively to the level of productivity in the capital sector.