Good Housekeeping? Reputation, Fixed Exchange Rates, and the 'Original Sin' Problem

This paper examines how the choice of exchange rate regime can signal financial rectitude and, in so doing, influcence a country's ability to borrow internationally in domestic currency. We develop a model in which the constant probability of a 'type change' creates incentives for disciplined policymakers to fix the exchange rate in an effort to separate themselves from more opportunistic types. Because the track record of a policymaker is imperfectly observable, reputational incentives depend on the past behaviour of previous generations and there is hysterisis in the updating behaviour of creditors. 'Original Sin' - the inflationary track record of one's predecessors - can reverberate over time leading creditors to be wary about extending sovereign loans in domestic currency terms. Our findings seem consistent with the pattern of the currency composition of debt in Japan and Russia at the turn of the nineteenth century.International Monetary Arrangement, Foreign Currency Debt, Reputation

Woodford goes to Africa

This paper analyses the effects of inflation shocks, demands shocks, and aid shocks on low-income, quasi-emerging-market economies, and discusses how monetary policy can be used to manage these effects. We make use of a model developed for such economies by Adam et al. (2007). We examine the e¤ects of four things which this model features, which we take to be typical of such economies. These are: the existence of a tradeables/non-tradeables production structure, the fact that international capital movements are - at least initially - confined to the effects of currency substitution by domestic residents, the use of targets for financial assets in the implementation of monetary policy, and the pursuit, in some countries, of a fixed exchange rate. We then modify the model to examine the effect on such economies of three major changes, changes which we take to be part of the transition by such economies towards more fully- fledged emerging-market status: an opening of the capital account so that uncovered- interest-parity comes to hold, a move to floating exchange rates, and the replacement of fixed stocks of financial aggregates by the pursuit of a Taylor rule in the conduct of monetary policy.currency substitution, emerging market macroeconomics, interactions between fiscal and monetary policy, Taylor rule

Essays on learning in international macroeconomics

The objective of this thesis is to explore the implications of learning as an alter- native expectations formation mechanism in international macroeconomics. The first part of the thesis (Chapters 2 to 4) deals with the e¤ects of adaptive learning(Evans and Honkapohja, 2001) in the transmission of policy changes and shocks within and across borders. In particular, learning has been introduced to two major workhorse open economy models: the Mundell-Fleming Dornbusch and the McKibbin-Sachs Global (MSG3) models. The second part of the thesis (Chapters 5 to 6) begins by examining the learning behavior of international creditors about the credibility of an exchange rate regime using a game theoretic approach to reputation. Using the Pooled Mean Group methodology, this part also conducts an empirical analysis to investigate the inter-relationship between sovereign yield spreads and exchange rate regime during the pre-World War One era..

Learning and International Transmission of Shocks

This paper studies the implications of adaptive learning in the modelling of inter-country linkages in a two-region MSG G-cubed model built on micro-founded behaviors of firms and households. The nature of the transmission process under rational expectations versus adaptive learning is explored. We investigate the propagation mechanism within and across borders for various shocks and policy changes within the United States: change in inflation target, fiscal policy, productivity shock, and rise in equity risk. Adaptive learning is found to change the short run sign of transmission in most cases but this also depends on the fraction of forward-looking agents in the economy

A multi-control vehicle-to-grid charger with bi-directional active and reactive power capabilities for power grid support

This paper proposes a multi-control vehicle-to-grid charger with bi-directional power capability. The proposed charger can perform vehicle battery charging and discharging operations, as well as power grid support such as reactive power compensation, power factor correction, and grid voltage regulation. The performances of the charger controls were examined under various power grid scenarios. Results revealed that the vehicle-to-grid charger attained the highest charger efficiency when operating at unity power factor mode. Nevertheless, vehicle charging at unity power factor introduced a significant grid voltage drop which may violate the grid voltage limits. This problem was solved by using the voltage control, which injected reactive power to the power grid for accurate voltage regulation. This paper also proposed an autonomous multi-control selection algorithm to intelligently switch between the multiple charger controls in response to the power grid condition. Results showed that the proposed algorithm effectively instructed the charger to work in efficient control modes if the grid voltage was within the permissible voltage limits. Whenever the grid voltage exceeded the limits, the charger automatically switched to grid voltage control for power grid voltage regulation

Machine learning classification models for fetal skeletal development performance prediction using maternal bone metabolic proteins in goats

Background: In developing countries, maternal undernutrition is the major intrauterine environmental factor contributing to fetal development and adverse pregnancy outcomes. Maternal nutrition restriction (MNR) in gestation has proven to impact overall growth, bone development, and proliferation and metabolism of mesenchymal stem cells in offspring. However, the efficient method for elucidation of fetal bone development performance through maternal bone metabolic biochemical markers remains elusive. Methods: We adapted goats to elucidate fetal bone development state with maternal serum bone metabolic proteins under malnutrition conditions in mid- and late-gestation stages. We used the experimental data to create 72 datasets by mixing different input features such as one-hot encoding of experimental conditions, metabolic original data, experimental-centered features and experimental condition probabilities. Seven Machine Learning methods have been used to predict six fetal bone parameters (weight, length, and diameter of femur/humerus). Results: The results indicated that MNR influences fetal bone development (femur and humerus) and fetal bone metabolic protein levels (C-terminal telopeptides of collagen I, CTx, in middle-gestation and N-terminal telopeptides of collagen I, NTx, in late-gestation), and maternal bone metabolites (low bone alkaline phosphatase, BALP, in middle-gestation and high BALP in late-gestation). The results show the importance of experimental conditions (ECs) encoding by mixing the information with the serum metabolic data. The best classification models obtained for femur weight (Fw) and length (FI), and humerus weight (Hw) are Support Vector Machines classifiers with the leave-one-out cross-validation accuracy of 1. The rest of the accuracies are 0.98, 0.946 and 0.696 for the diameter of femur (Fd), diameter and length of humerus (Hd, Hl), respectively. With the feature importance analysis, the moving averages mixed ECs are generally more important for the majority of the models. The moving average of parathyroid hormone (PTH) within nutritional conditions (MA-PTH-experim) is important for Fd, Hd and Hl prediction models but its removal for enhancing the Fw, Fl and Hw model performance. Further, using one feature models, it is possible to obtain even more accurate models compared with the feature importance analysis models. In conclusion, the machine learning is an efficient method to confirm the important role of PTH and BALP mixed with nutritional conditions for fetal bone growth performance of goats. All the Python scripts including results and comments are available into an open repository at https://gitlab.com/muntisa/goat-bones-machine-learning

Building Standard Offline Anti-phishing Dataset for Benchmarking

Anti-phishing research is one of the active research fields in information security. Due to the lack of a publicly accessible standard test dataset, most of the researchers are using their own dataset for the experiment. This makes the benchmarking across different antiphishing techniques become challenging and inefficient. In this paper, we propose and construct a large-scale standard offline dataset that is downloadable, universal and comprehensive. In designing the dataset creation approach, major anti-phishing techniques from the literature have been thoroughly considered to identify their unique requirements. The findings of this requirement study have concluded several influencing factors that will enhance the dataset quality, which includes: the type of raw elements, source of the sample, sample size, website category, category distribution, language of the website and the support for feature extraction. These influencing factors are the core to the proposed dataset construction approach, which produced a collection of 30,000 samples of phishing and legitimate webpages with a distribution of 50 percent of each type. Thus, this dataset is useful and compatible for a wide range of anti-phishing researches in conducting the benchmarking as well as beneficial for a research to conduct a rapid proof of concept experiment. With the rapid development of anti-phishing research to counter the fast evolution of phishing attacks, the need of such dataset cannot be overemphasised. The complete dataset is available for download at http://www.fcsit.unimas.my/research/legit-phish-set

Ruptured duodenal varices arising from the main portal vein successfully treated with endoscopic injection sclerotherapy: a case report

Duodenal varices result from retroperitoneal portosystemic shunts that usually come from the pancreaticoduodenal vein and drain into the inferior vena cava. Because they are a rare but fatal cause of gastrointestinal bleeding, a prompt hemostatic intervention is mandatory. A 62-year-old man who had a history of excessive alcohol consumption presented with massive hematemesis and melena. Emergent endoscopy revealed ruptured varices with an adhering whitish fibrin clot on the postbulbar portion of the duodenum. Abdominal computed tomography demonstrated a cirrhotic liver with venous collaterals around the duodenum and extravasated contrast in the second and third portions. The collaterals originated from the main portal vein and drained via the right renal vein into the inferior vena cava. Endoscopic injection sclerotherapy with cyanoacrylate was successful in achieving hemostasis, and resulted in the near eradication of duodenal varices at a 6-month follow-up

Revolutionizing Connectivity: The Breakthrough of Batteryless Mouse Using Magnetic Resonant Coupling for Communication Devices

With the rapid development of electronic technology and information technology, personal computer has gradually become the public's office or entertainment tools, which also makes the computer mouse a widely used tool. However, most computer mouse on the market today come with batteries. In this context, it is necessary to design a batteryless mouse that without using power supply such as battery. In view of such demand, on the basic of theoretical analysis, this paper summarizes and designs a classical wireless transmission structure – magnetic resonant coupling and antenna that used to transmit and received power for communication devices. In order to understand the operation of wireless power transmission technology, the paper analysed antenna construction and wireless power transmission technology. The basic design parameters of the axial mode helical antenna structure are also explained. Finally, by using CST STUDIO software, axial mode helical antenna with gain of 6.45 dBi was obtained. The system's output voltage is successfully simulated at 1.516 V that can powered up the computer mouse