The effects of population aging on optimal redistributive taxes in an overlapping generations model

The impact of population aging on the steady state solution to a Ordover-Phelps (1979) overlapping generations optimal nonlinear income tax problem with two types of workers and quasilinear-in-leisure preferences is investigated. A decrease in the rate of population growth, which leads to an aging population, increases the relative price of consumption per person in retirement, which tends to decrease optimal consumption for retirees of both skill types. It is also shown that the optimal steady state rate of interest equals the rate of population growth. As a result, the steady state interest rate unambiguously declines when the rate of population growth declines. The resulting adjustments in production plans has an ambiguous effect on the aggregate wage rate. This article identifies factors contributing to an increase in the aggregate wage when the population ages, namely normality of consumption in retirement, complementarity between capital and labor in production, and a large capital deepening effect relative to the increase in dependency owing to demographic change. Depending on the sign of this wage effect, ambiguities may arise in the direction of change in the optimal steady state consumption and production plans. It is also shown that the optimal marginal income tax rates are independent of the rate of population growth.optimal income taxation; overlapping generations model; population aging

Workforce or Workfare?

This article explores the use of workfare as part of an optimal tax mix when labor supply responses are along the extensive margin. Particular attention is paid to the interaction between workfare and an earned income tax credit, two policies that are designed to provide additional incentives for individuals to enter the labor force. This article shows that, despite their common goal, these policies are often at odds with each other.extensive margin, optimal income taxation, workfare

Workforce or Workfare?

This article explores the use of workfare as part of an optimal tax mix when labor supply responses are along the extensive margin. Particular attention is paid to the interaction between workfare and an earned income tax credit, two policies that are designed to provide additional incentives for individuals to enter the labor force. This article shows that, despite their common goal, these policies are often at odds with each other.Extensive margin; optimal income taxation; workfare

CAPITAL TAXATION IN A SIMPLE FINITE-HORIZON OLG MODEL

In a simple finite-horizon overlapping-generations model where the government has the power to levy commodity taxes and to implement uniform lump-sum transfers, and individuals as well as the government can purchase units of a storable good in order to transfer resources from the present to the future, we derive the equations that implicitly define the taxes and subsidies that are part of the second-best Pareto optima. In this context we first show that there is production efficiency. We then show that taxes on capital income/savings are required at almost all Pareto optima. Finally we show that there are no restriction on preferences or technologies that are consistent with a general exemption of capital income/savings from the tax base.overlapping generations ; capital taxes ; tax-reform

“I am an American”: Communicating Refugee Identity and Citizenship

This study examines the messages in a citizenship preparation class being utilized by refugees and instructors. Through an ethnographic study of a citizenship class at an urban community center in a Midwestern city, an examination of these messages reveals assimilationist expectations and norms for refugees adjusting to American society. Responses from the refugees reveal how these messages are being either accepted or resisted as they negotiate new identities. A contradiction was found between what the citizenship class teaches and the perceptions of refugees regarding the meanings of American citizenship. In particular, refugees reported to often face a difficult situation in which their legal status upon becoming American citizens is not readily acknowledged by the perceptions of other Americans

Constructing the Self through the Other: How beliefs about the Other inform international NGO approaches to development

The perspectives of development organizations and workers regarding recipients of international development inform their practice and approach to development work. The recent surge of international nongovernmental organizations (NGOs) involved in development work around the world provides a rationale for examining how the accounts of members of such organizations reflect beliefs about themselves and about those they serve. This study sought to explore some of the beliefs and perspectives of volunteers of an international NGO headquartered in the United States and how these perspectives influence their projects and interactions with local peoples. Thirty in-depth, semi-structured interviews were conducted of members of Rotary International, one of the largest NGOs in the world. Interviewees were asked to talk about their experiences with international service through Rotary International. Using an open and axial coding technique (Lindlof & Taylor, 2002; Miles & Huberman, 1994), this study revealed that these volunteers' accounts of their experience in international service serve to position volunteers and recipients of service in a relationship. Volunteers, through their accounts of their perspectives and experiences, describe recipients of service projects in ways that serve to affirm the desired self-understanding the volunteers have of themselves. Furthermore, this relationship between understanding the self and others was found in this study to reveal a contradiction between expressed values and practices. These volunteers gave accounts of their approaches to international service in which their descriptions of themselves and recipients as well as the projects actually carried out contradicted their preferred approach to service. In analyzing these volunteers' accounts, this study makes theoretical contributions by a) demonstrating how social groups can enact ingroup favoritism and positive group distinction in a context of helping rather than competing; b) revealing how in the context of international service and development volunteers construct a dialectical understanding of the self and the international recipient; and c) explaining the process of Othering as not only for domination but in a complimentary fashion that constructs the other as wanting and needing what the self wants to give

In-situ pull testing of cable bolts encapsulated with injection polyurethane

Polyurethane (PUR) injection into underground coal mine strata has been practiced in Australia as early as 1985. The ACARP report C100019 discussed several case studies of which one included PUR injection into resin anchored, pre-tensioned hollow central tube cable bolts. In cases of rapid response to accelerating strata movement it is the preference of site geotechnical personnel to install immediate pre-tensioned cable support, followed by re-consolidation of the strata through injection of grout or PUR. Cementitious grouting of cable bolts has two operational time restrictions; 1) 24-48 h restrictions can be placed on roadway widening or longwall chock removal while waiting for the grout to achieve adequate strength and 2) a 24 h restriction being placed on PUR injection after grouting has taken place to avoid unwanted chemical reactions and heat generation. In the last few years, more mines, faced with time critical ground support, have been utilising hollow cable bolts as the support and the means of injecting PUR into the strata. The main reason is time, 24 h lost to cementitious grout curing could be used in stabilising the strata by PUR injection into distant fractures, and operationally 24 h gained on a longwall move represents a large financial advantage. It has been considered that foregoing cementitious grouting of cables and replacing it with PUR will reduce the load transfer of the cable bolt, but no readily available data exists on how much reduction in bond strength occurs. Underground short encapsulation cable pull tests were conducted at Springvale Colliery comparing cementitious grout against PUR at both 24 h and nine days cure time

Capital taxation in a simple finite-horizon OLG model

In a simple finite-horizon overlapping-generations model where the government has the power to levy commodity taxes and to implement uniform lump-sum transfers, and individuals as well as the government can purchase units of a storable good in order to transfer resources from the present to the future, we derive the equations that implicitly define the taxes and subsidies that are part of the second-best Pareto optima. In this context we first show that there is production efficiency. We then show that taxes on capital income/savings are required at almost all Pareto optima. Finally we show that there are no restriction on preferences or technologies that are consistent with a general exemption of capital income/savings from the tax base

In situ mixing of organic matter decreases hydraulic conductivity of denitrification walls in sand aquifers

In a previous study, a denitrification wall was constructed in a sand aquifer using sawdust as the carbon substrate. Ground water bypassed around this sawdust wall due to reduced hydraulic conductivity. We investigated potential reasons for this by testing two new walls and conducting laboratory studies. The first wall was constructed by mixing aquifer material in situ without substrate addition to investigate the effects of the construction technique (mixed wall). A second, biochip wall, was constructed using coarse wood chips to determine the effect of size of the particles in the amendment on hydraulic conductivity. The aquifer hydraulic conductivity was 35.4 m/d, while in the mixed wall it was 2.8 m/d and in the biochip wall 3.4 m/d. This indicated that the mixing of the aquifer sands below the water table allowed the particles to re-sort themselves into a matrix with a significantly lower hydraulic conductivity than the process that originally formed the aquifer. The addition of a coarser substrate in the biochip wall significantly increased total porosity and decreased bulk density, but hydraulic conductivity remained low compared to the aquifer. Laboratory cores of aquifer sand mixed under dry and wet conditions mimicked the reduction in hydraulic conductivity observed in the field within the mixed wall. The addition of sawdust to the laboratory cores resulted in a significantly higher hydraulic conductivity when mixed dry compared to cores mixed wet. This reduction in the hydraulic conductivity of the sand/sawdust cores mixed under saturated conditions repeated what occurred in the field in the original sawdust wall. This indicated that laboratory investigations can be a useful tool to highlight potential reductions in field hydraulic conductivities that may occur when differing materials are mixed under field conditions

Final Report Resonance Ionization Mass Spectrometry for Post-Detonation Nuclear Forensics

Isotope ratio measurements of the actinide elements provide essential information for nuclear detonation forensics and proliferation detection. Resonance Ionization Mass Spectrometry (RIMS) is a high-sensitivity, elementally selective, laser-based form of mass spectrometry that offers the potential to determine the isotopic composition of materials without sample preparation. Due to the elementally selective approach of RIMS, basic research questions of atomic spectroscopy and the probability for producing neutral atoms in the gas phase, must be studied element by element. The studies carried out in this work represent basic research into the application and optimization of RIMS to the analysis of post-detonation debris