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Results are presented for Floquet calculations of photodetachment rates from a one-dimensional model atom irradiated by intense laser light. Light-induced quasibound states are found to originate from the movement of poles of the multichannel scattering matrix on the Riemann energy surface. The appearance of new bound states of the negative Hydrogen ion, recently predicted, is related to the motion of resonance poles that correspond to autoionising states in the absence of the field. A number of pole trajectories, leading to light-induced states, are discussed for the one-dimensional model atom. The Floquet method allows one to represent the wave function of a quantum system in a laser field, as an infinite sum of harmonic basis functions. In any practical calculation this infinite sum must be truncated. The consequences of representing the wave function, via the Floquet method, by a finite sum of harmonics is addressed. An illustration of these consequences is made by way of a number of representative calculations performed on a one-dimensional model atom. Results are presented of calculations performed to determine the influence of a laser field, of low to moderate intensity, upon the partial and total photodetachment rates of the negative Hydrogen ion, H(^-). Using the R-matrix Floquet method, a study is undertaken into the detachment of an electron from the ion, via multiphoton transitions through one of several autodetaching resonances of the ion. The discussion focuses on the influence of the laser field upon auto detaching pathways. It is found that the laser may induce structure into the continuum that does not exist in the absence of the laser field, or, conversely, may suppress field-free structure. In the latter case, the suppression of structure is related to the appearance of laser-induced degeneracies.

<p>Since the 1980s China had different exchange rate regimes. For example, in 1981, a dual-exchange rate system was introduced, with the official exchange rate applying to non-trade-related foreign exchange transactions and the depreciated internal settlement rate (ISR) applying to trade related transactions. This system was discontinued in 1985, but after the establishment of special economic zones to boost the country&rsquo / s export performance, the dual-exchange rate system was reintroduced in 1986. In 1994 the country informed the IMF that it will be switching to a managed floating exchange rate system and this was the official policy for almost ten years. However, de facto, the country chose to peg its currency to the USD during all these years (whilst Japan was the most important trading partner).</p> <p><br /> The report provides a descriptive analytical overview of how China in this era of globalization and with the importance of the World Trade Agreement, managed to keep its currency pegged to the USD over such a long period of time. The most important factors explaining this choice were identified as the desire to stimulate export-let economic growth, the risk related to capital mobility, financial sector liberalization, relative price level stability, dollarization and politics.</p>

The class of beta regression models is commonly used by practitioners to model variables that assume values in the standard unit interval (0, 1). It is based on the assumption that the dependent variable is beta-distributed and that its mean is related to a set of regressors through a linear predictor with unknown coefficients and a link function. The model also includes a precision parameter which may be constant or depend on a (potentially different) set of regressors through a link function as well. This approach naturally incorporates features such as heteroskedasticity or skewness which are commonly observed in data taking values in the standard unit interval, such as rates or proportions. This paper describes the betareg package which provides the class of beta regressions in the R system for statistical computing. The underlying theory is briefly outlined, the implementation discussed and illustrated in various replication exercises. / Series: Research Report Series / Department of Statistics and Mathematics

M.Sc. (Mathematical Statistics) / In this dissertation we investigate the South-African interest rate market by analyzing the Johannesburg Interbank Agreed rate (JIBAR) and the South-African three-month treasurybill rate. In particular, we assess the goodness-of-fit of some well known parametric singlefactor short rate models. In all the data sets investigated, we firstly found the interest rate increments to exhibit severe nonnormalities, which is also found to be the case in numerous other empirical studies. Secondly, we reject the model fit for the various parametric short rate models tested. Thirdly, we found strong evidence to support the presence of jumps in all the data sets and that interest rate increments mostly exhibit fat-tailed distributions. Consequently, we tested the ability of diffusion models, driven by Brownian motions, to generate jump induced nonnormalities via a nonparametric test of diffusion model fit. The nonparametric short rate model was rejected, i.e diffusion models are misspecified. Lastly, since diffusion models are misspecified we investigated whether a jump-diffusion model can be fitted to the data with higher accuracy. In conclusion we find that a jump-diffusion model, namely the Vasiˇcek jump-diffusion model, can adequately generate the jump induced nonnormalities present in each of the data sets.

This dissertation empirically and theoretically investigates three interrelated issues of market anomalies in interest rates derivatives and foreign exchange rates. The first essay models the spot exchange rate as a decomposition of permanent and transitory components. Unlike extant analysis, the transitory component could be stationary or explosive. The second essay examines the market efficiency hypothesis in the foreign exchange markets and relates the rejection of forward rate unbiasedness hypothesis to the existence of risk premium not to the failure of rational expectation. The third essay examines the behavior of short-term riskless rate and models the risk free rate as a nonlinear trend stationary process. While addressing these issues, these essays account for: (1) finite sample bias; (2) Unit root and other nonstationary behaviors; (3) the role of nonlinear trend; and (4) the interrelations between different behaviors. Several new results have been gleaned from our analysis; we find that: (1) the spot exchange rates display a very slow mean aversion behavior, which implies the failure of the purchasing power parity; (2) there are positive autocorrelations across the long horizons overlapping returns increases overtime and then begin to decline at a very long horizon period; (3) the short-term riskless rate displays a nonlinear trend stationary process which is closer to driftless random walk behavior; (4) modifying the mean reverting shortterm interest rates models to a nonlinear trend stationary shows an extreme improvement and outperforms all suggested models; (5) the traditional tests for rational expectations and market efficiency in the foreign exchange markets are subject to size distortions; (6) we relate the rejection of market efficiency in the foreign exchange markets documented across most currencies to the existence of risk premium not to the rejection of rational expectation hypothesis.

A Thesis submitted to the Faculty of Commerce of the University of the Witwatersrand, Johannesburg, for the degree of Doctor of Philosophy December 1978 / The breakdown of the system of fixed exchange rates, which occurred in the western world in the early 1970s, has exerted marked effects upon the exchange rate policies adopted by South Africa. In particular, it has resulted in the local monetary authorities practising a more active policy concerning the exchange rate value of the rand. The purpose of this thesis is to describe and analyze the exchange rate policies of the Renublic during the period from 1971 to 1977, and to offer recommendations For change. The research procedure followed involved extensive gathering of information from published literature, together with confidential information disclosed to the writer by the Deputy Governor of the Reserve Bank. The thesis is divided into four sections. Section A reviews the traditional exchange rate policy adopted by the South African authorities, and their long-standing support for fixed but adjustable exchange rates in the international monetary system. Section B incorporates on historical review and analysis of changes in the exchange rate for the rand which have materialised since 1971. Section C focuses attention upon the attitudes of the local authorities over the issue of reform of the exchange rate regime in the international monetary system in the past few years. Section D is devoted to an analysis of specific policy issues which have arisen in the conduct of exchange rate policy in South Africa, and highlights areas where improvements could be made. All four chapters in this Section were submitted as evidence to the current Commission of Inquiry into the Monetary System and Monetary Policy in South Africa. One important conclusion of the study is that the more flexible exchange rate policy adopted in South Africa has had very limited success in affecting positively the current account of the balance of payments. Conversely exchange rate policy appears to have been more successful in improving the position on tht capital account. (iv) Another conclusion concerns deficiencies which exist in the provision of foreign exchange facilities, and particularly in regard to forward exchange. In some respects South African policy is characterized by exchange rates and facilities which bear little relation to market conditions. It is recommended that j mor># competitive market in foreign exchange should be established in both spot and forward transactions.

South Africa‟s high telecommunication costs are attributed partly to high interconnection rates. High costs negatively impact developmental objectives. This paper analyses the processes engaged in by ICASA in regulating interconnection rates, using a qualitative case study methodology. Enabling legislation, regulatory administration and rules and the bringing to bear of regulatory rules on institutions are stages of regulatory processes that are examined. Perspectives are taken from processes executed by TRAI, India‟s regulatory authority. South Africa followed a market review process which contrasts with India‟s cost-based process. South Africa‟s process although arduous did not achieve the desired result of establishing cost based rates. The root cause is attributed to a combination of factors that include an onerous market review process prescribed by the ECA, institutional problems at ICASA and a politically driven process that ran alongside and engulfed the process managed by ICASA. India‟s process meanwhile has yielded some of the cheapest telecoms retail rates in the world. Gaps exist between processes in the two countries and lessons learnt provide an improved understanding of South African shortcomings.

Chiang Lok Man Cally. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 29-31). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Literature Review --- p.4 / Chapter 2.1 --- Studies against the trading rule profits --- p.4 / Chapter 2.2 --- Studies for the trading rule profits --- p.5 / Chapter 3 --- Data Descriptions and Methodology --- p.8 / Chapter 4 --- Empirical Results --- p.14 / Chapter 4.1 --- First trading rule --- p.14 / Chapter 4.2 --- Second trading rule --- p.19 / Chapter 4.3 --- Comparison between the two trading rules --- p.23 / Chapter 5 --- Other Related Results --- p.25 / Chapter 6 --- Conclusions --- p.27 / Reference --- p.29 / Figure 1 - 12 --- p.32 / Table 1 - 14 --- p.44

The coastline of the northern Gulf of Mexico (NGOM) represents important non-breeding habitats for 28 species of migratory shorebirds. As processes of climate change accelerate, these habitats are expected to experience dramatic land loss. In addition, the NGOM has experienced several natural and human mediated disasters over the last decade, including Hurricane Katrina and the Deepwater Horizon Oil spill (DWH). Predicting the impacts of these events requires an understanding of the interactions between shorebirds and their habitats. However, the migration ecology of shorebirds on the NGOM has not been well studied. To better understand the effects of the DWH and the importance of NGOM habitats to the migration ecology of shorebirds I carried out two related studies. First, I investigated the potential for long term, large-scale effects of oil exposure to migratory shorebirds through both a literature review, and by investigating the exposure to DWH oil in seven species of shorebirds that winter or stopover along the NGOM. I found that through migratory carry-over effects, oil spills and other environmental disasters, have the potential to impact ecosystems far from the event. Exposure results suggest as many as 1 million shorebirds were impacted by direct exposure to oil, and many more may have been negatively affected by disturbance from cleanup activities in oiled habitats. Second, I investigated the migration ecology of three near-arctic breeding species of shorebirds (Semipalmated sandpipers (Calidris semipalmatus), Western Sandpiper (C. mauri) and Dunlin (C. alpina), by measuring within- and among-species variation in habitat use, stopover duration, and refueling rates, as measured by plasma metabolites, across 3 habitat types. I found that among species, shorebirds vary in their migration ecology according to the distance to the next stopover site, suggesting NGOM habitats may be particularly important to longer-distance â"u20acœjumpâ"u20acù migrants (Dunlin). I also found that while shorebirds are found across all habitat types sampled, the back bay habitats of barrier islands provided a higher quality habitat (as evidenced by higher prey biomass, and a higher refueling rate) than traditional coastal mudflats or remnant wetlands, highlighting the importance of considering shorebird ecology in barrier island restoration plans. / 1 / Jessica Renee Henkel