Market Wages, Reservation Wages, and Retirement Decisions

The paper is an empirical cross-section study of the retirement decisions of American white men between the ages of 58 and 67. predicated on the theoretical notion that an individual retires when his reservation wage exceeds his market wage. Reservation wages are derived from an explicit utility function in which the most critical taste parameter is assumed to vary both systematically and randomly across individuals. Market wages are derived from a standard wage equation adjusted to the special circumstances of older workers. The two equations are estimated jointly by maximum likelihood, which takes into account the potential selectivity bias inherent in the model (low-wage individuals tend to retire and cease reporting their market wage). The model is reasonably successful in predicting retirement decisions, and casts serious doubt on previous claims that the social security system induces many workers to retire earlier than they otherwise would. The normal effects of aging (on both market and reservation wages) and the incentives set up by private pension plans are estimated to be major causes of retirement.

A rapid method for optimization of the rocket propulsion system for single-stage-to-orbit vehicles

A rapid analytical method for the optimization of rocket propulsion systems is presented for a vertical take-off, horizontal landing, single-stage-to-orbit launch vehicle. This method utilizes trade-offs between propulsion characteristics affecting flight performance and engine system mass. The performance results from a point-mass trajectory optimization program are combined with a linearized sizing program to establish vehicle sizing trends caused by propulsion system variations. The linearized sizing technique was developed for the class of vehicle systems studied herein. The specific examples treated are the optimization of nozzle expansion ratio and lift-off thrust-to-weight ratio to achieve either minimum gross mass or minimum dry mass. Assumed propulsion system characteristics are high chamber pressure, liquid oxygen and liquid hydrogen propellants, conventional bell nozzles, and the same fixed nozzle expansion ratio for all engines on a vehicle

An automatically-shifted two-speed transaxle system for an electric vehicle

An automatic shifting scheme for a two speed transaxle for use with an electric vehicle propulsion system is described. The transaxle system was to be installed in an instrumented laboratory propulsion system of an ac electric vehicle drive train. The transaxle which had been fabricated is also described

HOPE Longitudinal Study: Year 2 Results

Abstract pending

Bank lending and monetary policy: evidence on a credit channel

While there is widespread agreement that banks play a key part in the transmission of monetary policy actions to the economy, debate continues on whether bank lending plays a special part in the monetary transmission mechanism. If a special lending or credit channel exists, changes in the willingness and ability of banks to extend credit may have implications for the economy. Moreover, ongoing changes in the role of banks in financial markets may affect the credit channel and so alter the monetary transmission mechanism.> Recent research on a bank credit channel has focused on two questions. Are certain borrowers so dependent on bank lending that any change in banks' willingness to lend has an immediate effect on investment and spending decisions? And, do monetary policy changes directly constrain bank lending? Both conditions are necessary for bank lending to play a special role in the monetary transmission mechanism.> Morris and Sellon provide insight into the second question--whether bank lending is constrained by monetary policy. The authors analyze how banks adjust the amount and terms of business lending when monetary policy is tightened. The analysis differs from previous research by using a more precise measure of monetary policy actions, which allows a more accurate identification of episodes of monetary tightening. The authors suggest that bank business lending is not constrained by restrictive monetary policy. Thus, Morris and Sellon conclude, monetary policy does not operate through a special credit channel.Bank loans ; Monetary policy

The discount window : time for reform?

For many years, the Federal Reserve's discount window has played an important role in monetary policy. Discount window borrowing helps individual depository institutions manage their reserve accounts in the presence of unexpected deposit and payments flows. Improved reserve management, in turn, helps stabilize the overnight federal funds market by reducing the volatility of short-term interest rates. Moreover, announced changes in the Federal Reserve's discount rate have often signaled important shifts in the stance of monetary policy and have frequently been associated with large changes in market interest rates, exchange rates, and asset prices.> In the 1990s, however, fewer and fewer institutions have relied on the window to meet short-term credit needs. Consequently, the usefulness of the discount window in smoothing reserve imbalances and stabilizing interest rates may have been reduced. In addition, changes in monetary policy operating procedures and the formal announcement of monetary policy decisions by the Federal Reserve may have reduced the effectiveness of discount rate changes in influencing market interest rates and asset prices.> Hakkio and Sellon analyze the changing role of the discount window in monetary policy and examine the case for discount window reform. One alternative to the traditional discount window is a "Lombard-type" lending facility in which depository institutions can borrow more freely than under the current system but at a higher rate. While there appear to be good arguments in favor of modernizing the discount mechanism, a number of conceptual and practical issues must be addressed before implementing a Lombard-type lending facility. An additional consideration, going forward, is the projected reduction in the supply of Treasury debt over the next few years. A shrinking supply of Treasury securities could complicate the use of open market operations in providing reserves to the banking system and require the Federal Reserve to place greater emphasis on the discount window. Consequently, any redesign of the discount window would need to address this issue.Discount window ; Discount ; Monetary policy

An investigation into the perspectives of providers and learners on MOOC accessibility

An effective open eLearning environment should consider the target learner’s abilities, learning goals, where learning takes place, and which specific device(s) the learner uses. MOOC platforms struggle to take these factors into account and typically are not accessible, inhibiting access to environments that are intended to be open to all. A series of research initiatives are described that are intended to benefit MOOC providers in achieving greater accessibility and disabled learners to improve their lifelong learning and re-skilling. In this paper, we first outline the rationale, the research questions, and the methodology. The research approach includes interviews, online surveys and a MOOC accessibility audit; we also include factors such the risk management of the research programme and ethical considerations when conducting research with vulnerable learners. Preliminary results are presented from interviews with providers and experts and from analysis of surveys of learners. Finally, we outline the future research opportunities. This paper is framed within the context of the Doctoral Consortium organised at the TEEM'17 conference

Liquid-hydrogen rocket engine development at Aerojet, 1944 - 1950

This program demonstrated the feasibility of virtually all the components in present-day, high-energy, liquid-rocket engines. Transpiration and film-cooled thrust chambers were successfully operated. The first liquid-hydrogen tests of the coaxial injector was conducted and the first pump to successfully produce high pressures in pumping liquid hydrogen was tested. A 1,000-lb-thrust gaseous propellant and a 3,000-lb-thrust liquid-propellant thrust chamber were operated satisfactorily. Also, the first tests were conducted to evaluate the effects of jet overexpansion and separation on performance of rocket thrust chambers with hydrogen-oxygen propellants

Reconsidering the Work Disincentive Effects of Social Security

This paper shows that, contrary to commonly held views, the provisions of the social security law actually provide strong work incentives for older men. The reason is that, for most workers, higher current earnings lead to higher future social security benefits. These incentives have been particularly strong for workers under 65 years of age and, although they will be reduced somewhat when the 1977 amendments to the social security law become fully effective, they will remain substantial. The findings raise serious questions about recent econometric work attributing the decline in labor force participation rates of older men to the social security system.

The Mod-2 wind turbine development project

A major phase of the Federal Wind Energy Program, the Mod-2 wind turbine, a second-generation machine developed by the Boeing Engineering and Construction Co. for the U.S. Department of Energy and the Lewis Research Center of the National Aeronautics and Space Administration, is described. The Mod-2 is a large (2.5-MW power rating) horizontal-axis wind turbine designed for the generation of electrical power on utility networks. Three machines were built and are located in a cluster at Goodnoe Hills, Washington. All technical aspects of the project are described: design approach, significant innovation features, the mechanical system, the electrical power system, the control system, and the safety system