Demographic change, children's families and child support policy in the United States

This paper describes recent demographic trends affecting families in the United States and considers how these trends may alter the definition of "family." The paper focuses on trends that affect minor children's family experience. Demographic changes have increased the percentage of children for whom family membership and household membership do not coincide. As a result, rights to children and adults' responsibilities for children are less clearly defined now than in the past. This greater ambiguity affects child well-being because children's access to resources, both time and attention as well as material goods, depends on their ties to adults. U.S. family policies, such as the recent child support reforms, work against demographic trends by emphasizing biological over social ties and reinforcing the importance of biological parents' responsibilities to children.

Deferred compensation and gift exchange: an experimental investigation into multi-period labor markets

This paper examines the relationship between firms’ wage offers and workers’ supply of effort using a three-period experiment. In equilibrium, firms will offer deferred compensation: first period productivity is positive and wages are zero, while third period productivity is zero and wages are positive. The experiment produces strong evidence that deferred compensation increases worker effort; in about 70 percent of cases subjects supplied the optimal effort given the wage offer, and there was a strong effort response to future-period wages. We also find some evidence of gift exchange; worker players increased the effort levels in response to above equilibrium wage offers by a human, but not in response to similar offers by a computer. Finally, we find that firm players who are initially hesitant to defer compensation learn over time that it is beneficial to do so

High-Temperature Alkali Vapor Cells with Anti-Relaxation Surface Coatings

Antirelaxation surface coatings allow long spin relaxation times in alkali-metal cells without buffer gas, enabling faster diffusion of the alkali atoms throughout the cell and giving larger signals due to narrower optical linewidths. Effective coatings were previously unavailable for operation at temperatures above 80 C. We demonstrate that octadecyltrichlorosilane (OTS) can allow potassium or rubidium atoms to experience hundreds of collisions with the cell surface before depolarizing, and that an OTS coating remains effective up to about 170 C for both potassium and rubidium. We consider the experimental concerns of operating without buffer gas and with minimal quenching gas at high vapor density, studying the stricter need for effective quenching of excited atoms and deriving the optical rotation signal shape for atoms with resolved hyperfine structure in the spin-temperature regime. As an example of a high-temperature application of antirelaxation coated alkali vapor cells, we operate a spin-exchange relaxation-free atomic magnetometer with sensitivity of 6 fT/sqrt(Hz) and magnetic linewidth as narrow as 2 Hz.Comment: 8 pages, 5 figures. The following article appeared in Journal of Applied Physics and may be found at http://link.aip.org/link/?jap/106/11490

Chartering the Way to a Free and Appropriate Public Education (FAPE): The Challenges for Charter Schools to Provide FAPE

Charter schools are publicly funded schools that are an integral part of the school choice movement, following a market-model of education based on autonomy, competition, and choice. However, charter schools are also mandated to adhere to all laws and regulations in the Individuals with Disabilities Education Act (IDEA) when educating students with disabilities. The education of students with disabilities within the charter school environment can result in policy tensions. This paper will examine the salient issues surrounding special education as it pertains to the state, authorizer, and operator in the areas of transparency, processes, and outcomes

Some new results on electron transport in the atmosphere

The penetration, diffusion and slowing down of electrons in a semi-infinite air medium has been studied by the Monte Carlo method. The results are applicable to the atmosphere at altitudes up to 300 km. Most of the results pertain to monoenergetic electron beams injected into the atmosphere at a height of 300 km, either vertically downwards or with a pitch-angle distribution isotropic over the downward hemisphere. Some results were also obtained for various initial pitch angles between 0 deg and 90 deg. Information has been generated concerning the following topics: (1) the backscattering of electrons from the atmosphere, expressed in terms of backscattering coefficients, angular distributions and energy spectra of reflected electrons, for incident energies T(o) between 2 keV and 2 MeV; (2) energy deposition by electrons as a function of the altitude, down to 80 km, for T(o) between 2 keV and 2 MeV; (3) the corresponding energy depostion by electron-produced bremsstrahlung, down to 30 km; (4) the evolution of the electron flux spectrum as function of the atmospheric depth, for T(o) between 2 keV and 20 keV. Energy deposition results are given for incident electron beams with exponential and power-exponential spectra

Effects of backing plates on the electron exposure of thin polymer films

The effects of backing plates on the radiation dose received by thin nylon films were calculated using recently developed multilayer electron transport codes. The film dose increased with increasing atomic number of the backing plate. The estimated dose could be off by a factor of 2 or more if the backing plate were ignored in the calculations

The impact of public transportation and commuting on urban labour markets: evidence from the new survey of London life and labour, 1929-32

This paper examines the consequences of the commuter transport revolution on working-class labour markets in London, circa 1930. Using GIS-based data constructed from the New Survey of London Life and Labour, we examine the extent of commuting and estimate the earnings returns to commuting. We show that commuting was an important feature for most working-class Londoners in the early-twentieth century. Using a variety of identifying procedures to address the endogeneity of distance commuted, we estimate a likely causal return of between 1.5 to 3.5 percent of earnings for each additional kilometre travelled. We also show that commuting was an important contributor to improvements in quality of life in the early-twentieth century

The impact of public transportation and commuting on urban labour markets: evidence from the New Survey of London Life and Labour, 1929-32

This paper examines the consequences of the commuter transport revolution on working class labour markets in 1930s London. The ability to commute alleviated urban crowding and increased workers’ choice of potential employers. Using GIS-based data constructed from the New Survey of London Life and Labour, we examine the extent of commuting and estimate the earnings returns to commuting. We obtain a lowerbound estimate of two percent increase in earnings per kilometre travelled. We also show that commuting was an important contributor to improving quality of life in the early-twentieth century