ObjectiveIn late 2019, the world faced a profound challenge with the emergence of the COVID-19 crisis, which had a lasting impact on economies across both developed and developing nations. The consequential impact reverberated through international financial markets, forcing their constriction and eventual closure as nations enforced sweeping nationwide quarantines. Simultaneously, healthcare expenditure soared, juxtaposed against a downturn in economic growth. Amid this upheaval, the domain of digital currencies, notably Bitcoin, experienced reverberations from the COVID-19 outbreak. Bitcoin's introduction signaled a new era of direct electronic payments and streamlined cross-border wealth transference, pivotal components underpinning the scaffolding of global trade. While COVID-19 doesn't solely account for the surge in Bitcoin prices, its presence likely played a sU.S.antial role, exacerbated by escalated uncertainties and risks amidst the global pandemic. The focal point of this study lies in examining the interplay between COVID-19 dynamics and the US Dollar Index on Bitcoin prices, utilizing Continuous Wavelet Transform (CWT) data spanning from April 8, 2020, to April 8, 2023. This study's novelty lies in its utilization of the Continuous Wavelet Transform, offering a distinctive edge within the realm of research on this subject. MethodsThe COVID-19 pandemic emerged as one of humanity's most daunting challenges in recent decades, significantly impacting digital currencies, epitomized by Bitcoin, as an indispensable economic sector. Primarily, this study aims to examine the complex effects of the COVID-19 pandemic and the US Dollar Index on Bitcoin prices over 977 days from April 2020 to April 2023, utilizing the Continuous Wavelet Transform (CWT). The research framework integrates two pivotal variables: the volume of confirmed COVID-19 cases per million and the tally of confirmed COVID-19 deaths per million. ResultsThe findings unravel a compelling correlation between the frequency of COVID-19 cases and associated fatalities with Bitcoin price fluctuations during the study's duration. Intriguingly, the impact of case occurrences seemingly eclipses that of mortalities, possibly rooted in escalated uncertainties and risks during the pandemic, igniting an amplified demand surge for Bitcoin as investors sought refuge to safeguard their wealth and assets. Conversely, the US Dollar Index emerges as a noteworthy antagonist, wielding a pronounced negative influence on Bitcoin prices throughout the study period, potentially attributed to the plausible sU.S.itution of two commodities functioning as currency. ConclusionThe study's findings reveal a clear positive impact of COVID-19 cases and deaths per million on Bitcoin prices during the observed period. This increase is largely driven by heightened demand, as investors, faced with risk and uncertainty, sought out Bitcoin as a safe-haven asset. On the flip side, the U.S. Dollar Index, acting as a competing asset, showed a significant negative effect on Bitcoin’s price during the same time. This is likely due to a sU.S.itution effect: as the U.S. Dollar strengthens, Bitcoin prices tend to decline.

In economic and financial literature, the relationship between exchange rate of the US Dollar and oil price is defined as a causality relationship between them which can be studied for long and short term periods. The mentioned relationship can be examined from a structural perspective by examining the demand and supply relationship for crude oil. On the other hand, information transmits reciprocally from one market to another. In order to investigate the mentioned relationships, this article has used the VECM-Multivariate GARCH method. The results of this study indicate that the causality relationship between the Dollar market and crude price is unidirectional in the long term from the foreign exchange to the crude market, while there is no causality in the reverse direction. The relationship between the exchange rate of the Dollar and crude prices is a negative one. Thus, while forecasting the long term price of crude and finding the elements which have long term effect on it, the trend rate of exchange of the US Dollar has to be considered. In terms of the spillover effect or risk transfer, we recognize that there is no spillover effect from crude to exchange rate markets while fluctuations of exchange rate market have a spillover effect on crude markets and part of the crude oil risk comes from the volatility of the exchange rate market.

The international role of the Dollar in the global economy remains dominant. Nonetheless, there is a belief that various factors, including geopolitical changes, technological advancements, and China's increasing role as an emerging power, may challenge the hegemony of the American Dollar as a dominant force. China has implemented a range of significant and diverse policies in pU.S.it of de-Dollarization to weaken one of the key pillars of American power. In this research, we employ an analytical-explanatory method and draw upon written and online sources, as well as data from financial and banking institutions, to address the fundamental qU.S.ion: What actions has China taken in pU.S.it of de-Dollarization, and to what extent have they been effective? The hypothesis proposed suggests that considering the Dollar's control over the financial structure and the international payment system, as well as the world's countries dependence, including China's, on the existing financial and monetary structure, Dollar hegemony has persisted despite China's confrontational policies and has not encountered significant challenges thus far. The research findings suggest that while China's de-Dollarization policy is acknowledged as a potential threat to Dollar hegemony, it has not succeeded in challenging the dominance of the American currency, and it appears that the Dollar-based system will continue predictably into the future.

Crude oil price and the U.S. effective exchange rate are two main economic variables that have had real effects on world welfare situation. The aim of this paper is to test whether there is a stable long-run relationship between oil prices and the U.S. Dollar, expressed in real term. To this end, we perform co-integration and causality tests between the two variables, using quarterly data from 1985: 1 to 2008: 4. Our results show that a 10% rise in the oil price coincides with a 1/8% depreciation of Dollar in long-run, and that the causality rU.S.from oil price to the Dollar. Furthermore, we estimate the Vector Error Correction Model (VECM) to analyze the short-run behavior of real effective exchange rate and the speed of adjustment when it deviates from its long-run path. Results show that the speed of adjustment is 4/3 percent for each period that means in each period (or each season) the deviation of real effective exchange rate Dollar from long-run path shrink to reach its long-run path.

Crude oil can be considered an engine of economic growth in the post Second World War era. In addition, given the economic supremacy of the USA, the US Dollar has been used for invoicing crude oil transactions throughout the world. The two economic indicators of crude oil price and US Dollar exchange rate and their fluctuations have a noteworthy effect on all countries, especially Iran. This article examines the long and short-run relationship between these variables. We apply the two methods of Johansen-Joselius and ARDL in order to rigorously study these relationships, using seasonal average prices of crude oil and effective exchange rates of the US Dollar for the period 1975 to 2008. According to our results, there is long run co-integration relation between real crude oil price and real effective exchange rate of the US Dollar, but this relationship is at a low level of statistical confidence. Also in the long-run, causality rU.S.from real price of crude oil to real effective Exchange rate of Dollar and not vice-versa. In short-run, real effective exchange rate of Dollar has stationary but gradually behavior in opposition to various shocks that deviate from its long-run path.

The relationship between financial and commodities markets is a challenging issue among regulators and investors, where the volatility of a market could affect other markets. This article’ s goal is analyzing the long-term relationship between six-year daily returns of alternative markets such as crude oil, Dollar, gold and Tehran stock market Index. We take advantage of VAR-GARCH to model markets returns and sU.S.quently to show relationship between these markets and using impU.S. response functions to describe the reaction of a market in response to a pU.S. in other markets. The results express that Tehran stock market total return Index (TEDPIX) return respectively is depend on its previous lag, crude oil, gold and Dollar returns and they are more sensitive to their shocks than market news.

Dynamism, variations in time, is the inherent characteristic of most economical phenomena. In econometrics, ignoring this dynamism may cause many problems due to over simplification of the problems. One such case occU.S.in application of static regression models to problems with dynamic nature. In so doing, one ignores the fact that the parameters of the model change in time, which may lead to misleading results. In this paper, we intend to exhibit the importance of this negligence in the context of a practical problem, namely modeling the weekly average rate of conversion of us Dollar into Iranian currency, Rial. Thus, two approaches of static and dynamic modeling are compared with respect to their efficiency in tracking the path of the variations of the US Dollar rate according to various criteria such as MAD and MSE of predictions. Using a dynamic time series model along with required interventions at outlier points superiority of the Bayesian dynamic model is shown.  

The persistence or decline of US Dollar as a pervasive international currency has been one of the most important issU.S.in the field of international political economy, since the beginning of the 21st century. While some scholars point to the continued dominance of US Dollar by citing the dominance of the United States in the world political and economic equations, others refer to the decline in the hegemony of this international currency due to the US economic weakness and its international alternatives. The present study aims to recognize the factors affecting the persistence or decline of US Dollar hegemony in the 21st century by using descriptive-analytical method based on considering available data and to examin the scenarios resulting from these situations. After raising this qU.S.ion that whether the hegemony of US Dollar as an international currency is still continuing or is facing a decline in the 21st century, this article is hypothesizing that despite the various factors affecting the continuation or decline of US Dollar hegemony, it seems that the continuity of US Dollar hegemony, as an international currency, will be strongly linked to the continuation of the existing international system and the US capability to keep it. The findings of this study in the framework of hegemonic stability theory show that the US Dollar hegemony will continue with some fluctuations depending on the willingness, volition and producing public goods by the United States in the short-and medium-term. However, in the long term, given the economic preponderance of China and other other emerging economies, a multi-currency monetary system may be formed in which the US Dollar would be a currency among other currencies.