Does volatility improve UK earnings forecasts?

We investigate the relation between UK accounting earnings volatility and the level of future earnings using a unique sample comprising some 10,480 firm-year observations for 1,481 non-financial firms over the 1985-2003 period. The findings confirm the in-sample result of an inverse volatility-earnings relation only for the 1998-2003 sub-period and for the most profitable firms. The out-of-sample forecast accuracy for the top earnings quintile when volatility is added as a regressor is superior to the model including only lagged earnings. The findings are consistent with the over-investment hypothesis and the view that the earnings of the most volatile firms tend to mean-revert more rapidly

The Origin of Life

The origin of life is in a sense a genetic problem, for, as H. J. Muller pointed out many years ago, the essential attribute that identifies living matter is its capacity to replicate itself and its variants (1). Because this uniquely biological property has its physical basis in proteins and nucleic acids, the goal of modern work on the origin of life is to discover the manner of origin of these polymers and of the interactions between them that constitute the genetic mechanism. In attempting to review this subject in a limited space, we cannot undertake an exhaustive treatment. Rather, we summarize work published principally since 1970 in the following areas, with emphasis on those aspects that are of greatest current interest: 1. precambrian paleontology, 2. chemical evolution of genetically important monomers, 3. prebiotic dehydration-condensation reactions, 4. organic compounds in meteorites and interstellar space, and 5. biological exploration of the planets. A large number of review articles (2-5), critical and theoretical discussions (6-8), books (9-16), and conference proceedings (17-21) dealing with the origin of have appeared in recent years. In addition, a new serial, the Journal of Molecular Evolution, publishing papers on this and related subjects, appeared in 1971; the journal Space Life Sciences has been renamed "Origins of Life," and a society, the International Society for the Study of the Origin of Life, was recently founded

Research in Natural Laminar Flow and Laminar-Flow Control, part 2

Part 2 of the Symposium proceedings includes papers addressing various topics in basic wind tunnel research/techniques and computational transitional research. Specific topics include: advanced measurement techniques; laminar flow control; Tollmien-Schlichting wave characteristics; boundary layer transition; flow visualization; wind tunnel tests; flight tests; boundary layer equations; swept wings; and skin friction

Combined riblet and lebu drag reduction system

The invention is a system of flow control devices which result in reduced skin friction on aerodynamic and hydrodynamic surfaces. The devices cause a breakup of large-scale disturbances in the boundary layer of the flow field. The riblet device acts to reduce disturbances near the boundary layer wall by the use of longitudinal striations forming V-shaped grooves. These grooves are dimensional on the order of the wall vortices and turbulent burst dimensions. The large eddy breakup device is a small strip or airfoil which is suspended in the upper region of the boundary layer. Various physical mechanisms cause a disruption of the large-scale vortices. The combination of the devices of this invention result in a substantial reduction in skin friction drag

Photocatalytic production of organic compounds from CO and H2O in a simulated Martian atmosphere

[14C]CO2 and [14C]organic compounds are formed when a mixture of [14C]CO and water vapor diluted in [12C]CO2 or N2 is irradiated with ultraviolet light in the presence of soil or pulverized vycor substratum. The [14C]CO2 is recoverable from the gas phase, the [14C]organic products from the substratum. Three organic products have been tentatively identified as formaldehyde, acetaldehyde, and glycolic acid. The relative yields of [14C]CO2 and [14C]organics are wavelength- and surface-dependent. Conversion of CO to CO2 occurs primarily at wavelengths shorter than 2000 angstrom, apparently involves the photolysis of water, and is inhibited by increasing amounts of vycor substratum. Organic formation occurs over a broad spectral range below 3000 angstrom and increases with increasing amounts of substratum. It is suggested that organic synthesis results from adsorption of CO and H2O on surfaces, with excitation of one or both molecules occurring at wavelengths longer than those absorbed by the free gases. This process may occur on Mars and may have been important on the primitive earth

Rate 3/4 coded 16-QAM for uplink applications

First phase development of an advanced modulation technology which synergistically combines coding and modulation to achieve 2 bits per second per Hertz bandwidth efficiency in satellite demodulators is nearing completion. A proof-of-concept model is being developed to demonstrate technology feasibility, establish practical bandwidth efficiency limitations, and provide a data base for the design and development of engineering model satellite demodulators. The basic considerations leading to the choice of 4 x 4 quadrature amplitude modulation (16-QAM) and its associated coding format are discussed, along with the basic implementation of the carrier and clock recovery, automatic gain control, and decoding process. Preliminary performance results are presented. Spectra for the modulated signal shows the effects of the square root Nyquist filters in the modulation. Bit error rate (BER) results for the encoder/decoder subsystem show near ideal results, although power consumption is high and baseband BER performance of the Nyquist filter set is poor. Recommendations regarding the present system to improve BER performance and acquisition speed are given

Tracking progress in trans-border regional economic development: Working paper series--99-01

A long-term program to foster economic development in a region encompassing two states in different countries has reached a point where indicators of progress are required. This article describes the development of a wide range of indicators of different aspects of economic activity and quality of life in the region. Sixty-eight separate indicators are grouped into five categories: NAFTA-related, regional economic integration, leading sectors, quality of life, and sustainable development. The article concludes with a discussion of challenges faced in tracking economic development progress in a binational context

Brief Note Blue Winged Warbler: Midseason Diet and Feeding Behavior

Author Institution: Department of Geography, University of Californi

POTENTIAL ANALYSIS OF RAINFALL-INDEXED INSURANCE IN ROMANIA

One of the key factors affecting the crop output is the rainfall volume. For this reason, insurance plans based on the rainfall deviation of the mean have been advanced. This paper provides prospects of rainfall-indexed insurance in Romania considering the tradeoff between moral hazard and basis risks. The reasonability of rainfall-indexed insurance will be judged first. The basic parameters will then be determined and the effectiveness will be measured. Finally, microfinance programs combined with indexed insurance will be advanced to deal with the basis risk problems, which also are the goals for further studyRisk and Uncertainty,