Bequests and heterogeneity in retirement wealth

Households hold vastly heterogeneous amounts of wealth when they reach retirement, and differences in lifetime earnings explain only part of this variation. This paper studies the role of intergenerational transmission of ability, voluntary bequest motives, and the recipiency of accidental and intended bequests (both in terms of timing and size) in generating wealth dispersion at retirement, in the context of a rich quantitative model. Modeling voluntary bequests, and realistically calibrating them, not only generates more wealth dispersion at retirement and reduces the correlation between retirement wealth and lifetime income, but also generates a skewed bequest distribution that is close to the one in the observed data

SwarMAV: A Swarm of Miniature Aerial Vehicles

As the MAV (Micro or Miniature Aerial Vehicles) field matures, we expect to see that the platform's degree of autonomy, the information exchange, and the coordination with other manned and unmanned actors, will become at least as crucial as its aerodynamic design. The project described in this paper explores some aspects of a particularly exciting possible avenue of development: an autonomous swarm of MAVs which exploits its inherent reliability (through redundancy), and its ability to exchange information among the members, in order to cope with a dynamically changing environment and achieve its mission. We describe the successful realization of a prototype experimental platform weighing only 75g, and outline a strategy for the automatic design of a suitable controller

UltraSwarm: A Further Step Towards a Flock of Miniature Helicopters

We describe further progress towards the development of a MAV (micro aerial vehicle) designed as an enabling tool to investigate aerial flocking. Our research focuses on the use of low cost off the shelf vehicles and sensors to enable fast prototyping and to reduce development costs. Details on the design of the embedded electronics and the modification of the chosen toy helicopter are presented, and the technique used for state estimation is described. The fusion of inertial data through an unscented Kalman filter is used to estimate the helicopter’s state, and this forms the main input to the control system. Since no detailed dynamic model of the helicopter in use is available, a method is proposed for automated system identification, and for subsequent controller design based on artificial evolution. Preliminary results obtained with a dynamic simulator of a helicopter are reported, along with some encouraging results for tackling the problem of flocking

Taxation, entrepreneurship, and wealth

Entrepreneurship is a key determinant of investment, saving, and wealth inequality. We study the aggregate and distributional effects of several tax reforms in a model that recognizes this key role and that matches the large wealth inequality observed in the U.S. data. The aggregate effects of tax reforms can be particularly large when they affect small and medium-sized businesses, which face the most severe financial constraints, rather than big businesses. The consequences of changes in the estate tax depend heavily on the size of its exemption level. The current effective estate tax system insulates smaller businesses from the negative effects of estate taxation, minimizing the aggregate costs of redistribution. Abolishing the current estate tax would generate a modest increase in wealth inequality and slightly reduce aggregate output. Decreasing the progressivity of the income tax generates large increases in output, at the cost of large increases in wealth concentration.Taxation

Wealth Inequality: Data and Models

In the United States wealth is highly concentrated and very unequally distributed: the richest 1% hold one third of the total wealth in the economy. Understanding the determinants of wealth inequality is a challenge for many economic models. We summarize some key facts about the wealth distribution and what economic models have been able to explain so far.

Entrepreneurship, frictions, and wealth

Although the role of financial constraints on entrepreneurial choices has received considerable attention, the effects of these constraints on aggregate capital accumulation and wealth inequality are less known. Entrepreneurship is an important determinant of capital accumulation and wealth concentration and, conversely, the distribution of wealth affects entrepreneurial choices in presence of borrowing constraints. We construct a model that matches wealth inequality very well, for both entrepreneurs and non- entrepreneurs. We find that more restrictive borrowing constraints generate less wealth concentration, but also reduce average firm size, aggregate capital, and the fraction of entrepreneurs. We also find that voluntary bequests are an important channel that allows some high-ability workers to establish or enlarge an entrepreneurial activity: with accidental bequests only, there would be fewer large firms, fewer entrepreneurs, and less aggregate capital, but also less wealth concentration.Loans ; Wealth

Taxation, entrepreneurship, and wealth

Entrepreneurship is a key determinant of investment, saving, and wealth inequality. We study the aggregate and distributional effects of several tax reforms in a model that recognizes this key role and that matches the large wealth inequality observed in the U.S. data. The aggregate effects of tax reforms can be particularly large when they affect small and medium-sized businesses, which face the most severe financial constraints, rather than big businesses. The consequences of changes in the estate tax depend heavily on the size of its exemption level. The current effective estate tax system insulates smaller businesses from the negative effects of estate taxation, minimizing the aggregate costs of redistribution. Abolishing the current estate tax would generate a modest increase in wealth inequality and slightly reduce aggregate output. Decreasing the progressivity of the income tax generates large increases in output, at the cost of large increases in wealthTaxation ; Wealth

Entrepreneurship, frictions, and wealth

Although the role of financial constraints on entrepreneurial choices has received considerable attention, the effects of these constraints on aggregate capital accumulation and wealth inequality are less known. Entrepreneurship is an important determinant of capital accumulation and wealth concentration and, conversely, the distribution of wealth affects entrepreneurial choices in the presence of borrowing constraints. We construct a model that matches wealth inequality very well, for both entrepreneurs and non-entrepreneurs, and find that more restrictive borrowing constraints generate less wealth concentration, but also reduce average firm size, aggregate capital, and the fraction of entrepreneurs. We also find that voluntary bequests are an important channel that allows some high-ability workers to establish or enlarge an entrepreneurial activity: with accidental bequests only, there would be fewer large firms, fewer entrepreneurs, and less aggregate capital, but also less wealth concentration.Saving and investment ; Wealth

Estate taxation, entrepreneurship, and wealth

We study the effects of abolishing estate taxation in a quantitative and realistic framework that includes the key features that policy makers are worried about: business investment, borrowing constraints, estate transmission, and wealth inequality. We use our model to estimate effective estate taxation. We consider various tax instruments to reestablish fiscal balance when abolishing estate taxation. We find that abolishing estate taxation would not generate large increases in inequality, and would, in some cases, generate increases in aggregate output and capital accumulation. If, however, the resulting revenue shortfall were financed through increased income or consumption taxation, the immensely rich, and the old among those in particular, would experience a welfare gain, at the cost of welfare losses for the vast majority of the population.Taxation ; Wealth

Estate Taxation, Entrepreneurship, and Wealth

We study the effects of abolishing estate taxation in a quantitative and realistic framework that includes the key features that policy makers are worried about: business investment, borrowing constraints, estate transmission, and wealth inequality. We use our model to estimate effective estate taxation. We consider various tax instruments to reestablish fiscal balance when abolishing estate taxation. We find that abolishing estate taxation would not generate large increases in inequality, and would, in some cases, generate increases in aggregate output and capital accumulation. If, however, the resulting revenue shortfall were financed through increased income or consumption taxation, the immensely rich, and the old among those in particular, would experience a welfare gain, at the cost of welfare losses for the vast majority of the population.