1,720,958 research outputs found
EXCHANGE-RATES FORECASTING: EXPONENTIAL SMOOTHING TECHNIQUES AND ARIMA MODELS
Full text linkThe exchange rate reflects the ratio at which one currency can be exchanged with another currency, namely the ratio of currency prices. The relevant literature implies, by the purchasing power parity theory, that in the long-run exchange rates converge to an equilibrium level. The question that arises is related to the behavior in the short-term of the exchange rates, and how these fluctuations might affect the financial market players, the investors as well as those directly influenced by changes in the exchange rate In this study we want to highlight the methods for exchange rate forecasting, using the exchange rates of Romanian Leu versus the most important currencies in terms of international trade, namely the Euro, United States Dollar, British Pound, Japanese Yen, Chinese Renminbi and the Russian Ruble. The relevant literature on currency forecasting issues includes a wide range of methods, the majority concentrating on models that are based on the random walk hypothesis in forecasting exchange rates, respectively those based on macroeconomic indicators. (Chinn and Meese:1995), (Mark:1995) (Hwang: 2001) consider the last ones more efficient, while (Meese and Rogof: 1983), (Goldberg and Frydman: 1996) indicate that the models based on the random walk hypothesis are superior. Others, like (Marsh and Power:1996), (Kilian and Taylor: 2001), (Zhang, Simoff and Debenham: 2006) use hybrid models. In the literature both types of models are used, but in the long-term the models based on macroeconomic indicators outperform those based on random walk, while in the short-term a more efficient predictability is achieved by the models based on random walk. To forecast the exchange rates the single exponential smoothing technique, double exponential smoothing technique, Holt -Winters simple exponential smoothing technique, Holt -Winters multiplicative exponential smoothing technique, Holt -Winters additive exponential smoothing technique namely the the autoregressive integrated moving average models were used. The forecasting results were measured by the indicators: Sum of squared errors, Root mean squared error, Mean absolute error, Bias Proportion, Variance Proportion, Covariance Proportion and the Theil Inequality Coefficient. All the results indicate the apreciation of the Romanian Leu against the other currencies. In the case of the first five forecast techniques the results are similar, from the point of view of the forecast coefficients, which points out that the optimal models were found. The exponential smoothing techniques in some cases outperform the ARIMA models, because of the speed eith which they addapt to the smallest changes to the market conditions. In addition, the ARIMA models present some difficulties in estimating and validating the model, are more effective in rendering the medium-term trend, in our case 4 months. So these models show the changes in trend, while the forecasting models based on exponential smoothing techniques are an effective tool for those interested in the evolution of the exchange rate. This work was possible with the financial support of the Sectoral Operational Programme for Human Resources Development 2007-2013, co-financed by the European Social Fund, under the project number POSDRU/107/1.5/S/77946 with the title "Doctorate: an Attractive Research Career ".Forecasting, Simple Exponential Smoothing, Double Exponential Smoothing, Holt-Winters Additive, Holt-Winters Multiplicative
EXCHANGE-RATES FORECASTING: EXPONENTIAL SMOOTHING TECHNIQUES AND ARIMA MODELS
No full textExchange rates forecasting is, and has been a challenging task in finance. Statistical and econometrical models are widely used in analysis and forecasting of foreign exchange rates. This paper investigates the behavior of daily exchange rates of the Romanian Leu against the Euro, United States Dollar, British Pound, Japanese Yen, Chinese Renminbi and the Russian Ruble. Smoothing techniques are generated and compared with each other. These models include the Simple Exponential Smoothing technique, as the Double Exponential Smoothing technique, the Simple Holt-Winters, the Additive Holt-Winters, namely the Autoregressive Integrated Moving Average model
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The Prospect of Euro Adoption in Romania
No full textTaking into account the schedule of Romania’s monetary integration: the entrance into Exchange Rate Mechanism II in 2012 and the euro adoption in 2014, our authorities have become preoccupied in accelerating the convergence process. This paper aims to analyze Romania’s progress in the convergence process, as well as, the current stage of the fulfilment of nominal and real convergence criteria required for euro adoption. In the same time we compare the results obtained by our country and those recorded in other Central and Eastern European states in the integration process. We also debate on the main reasons responsible for delaying the convergence process in Romania and the prospect of speeding up this process without a negative impact on the economy.nominal convergence, real convergence, euro adoption
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
The prospect of Euro adoption in Romania
Full text linkTaking into account the schedule of Romania’s monetary integration: the entrance
into Exchange Rate Mechanism II in 2012 and the euro adoption in 2014, our authorities
have become preoccupied in accelerating the convergence process. This paper aims to
analyze Romania’s progress in the convergence process, as well as, the current stage of the
fulfilment of nominal and real convergence criteria required for euro adoption. In the same
time we compare the results obtained by our country and those recorded in other Central
and Eastern European states in the integration process.
We also debate on the main reasons responsible for delaying the convergence
process in Romania and the prospect of speeding up this process without a negative impact
on the economy.peer-reviewe
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