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1.
Resources Policy ; 82, 2023.
Article in English | Scopus | ID: covidwho-2305896

ABSTRACT

Implied volatility index is a popular proxy for market fear. This paper uses the oil implied volatility index (OVX) to investigate the impact of different uncertainty measures on oil market fear. Our uncertainty measures consider multiple perspectives, specifically including climate policy uncertainty (CPU), geopolitical risk (GPR), economic policy uncertainty (EPU), and equity market volatility (EMV). Based on the time-varying parameter vector autoregression (TVP-VAR) model, our empirical results show that the impact of CPU, GPR, EPU, and EMV on OVX is time-varying and heterogeneous due to these uncertainty measures containing different information content. In particular, the CPU has become increasingly important for triggering oil market fear since the recent Paris Agreement. During the COVID-19 pandemic, CPU, EPU, and EMV, rather than GPR, play a prominent role in increasing oil market fear. © 2023 Elsevier Ltd

2.
Engineering Applications of Artificial Intelligence ; 123, 2023.
Article in English | Scopus | ID: covidwho-2305233

ABSTRACT

Reduction of the number of traffic accidents is a vital requirement in many countries over the world. In these circumstances, the Human–Robot Interaction (HRI) mechanisms utilization is currently exposed as a possible solution to recompense human limits. It is crucial to create a braking decision-making model in order to produce the optimal decisions possible because many braking decision-making approaches are launched with minimal performance. An effective braking decision-making system, named Optimized Deep Drive decision model is developed for making braking decisions. The video frames are extracted and the segmentation process is done using a Generative Adversarial Network (GAN). GAN is trained using the newly developed optimization technique known as the Autoregressive Anti Corona Virus Optimization (ARACVO) algorithm. ARACVO is created by combining the Conditional Autoregressive Value at Risk by Regression Quantiles (CAViaR) and Anti Corona Virus Optimization (ACVO) models. After retrieving the useful information for processing, the Deep Convolutional Neural Network (Deep CNN) is next used to decide whether to apply the brakes. The proposed approach improved performance by achieving maximum values of 0.911, 0.906, 0.924, and 0.933 for segmentation accuracy, accuracy, sensitivity, and specificity. © 2023 Elsevier Ltd

3.
Energy Economics ; 121, 2023.
Article in English | Scopus | ID: covidwho-2305099

ABSTRACT

We present a weekly structural Vector Autoregressive model of the US crude oil market. Exploiting weekly data we can explain short-run crude oil price dynamics, including variations related with the COVID-19 pandemic and with the Russia's invasion of Ukraine. The model is set identified with a Bayesian approach that allows to impose restrictions directly on structural parameters of interest, such as supply and demand elasticizes. Our model incorporates both the futures-spot price spread to capture shocks to the real price of crude oil driven by changes in expectations and US inventories to describe price fluctuations due to unexpected variations of above-ground stocks. Including the futures-spot price spread is key for accounting for feedback effects from the financial to the physical market for crude oil and for identifying a new structural shock that we label expectational shock. This shock plays a crucial role when describing the series of events that have led to the spike in the price of crude oil recorded in the aftermath of Russia's invasion of Ukraine. © 2023 Elsevier B.V.

4.
Journal of Cleaner Production ; 407, 2023.
Article in English | Scopus | ID: covidwho-2302141

ABSTRACT

In a low-carbon context, the connectedness among carbon, stock, and renewable energy markets has been strengthening. This study examines the effect of Brexit, the launch of the European Green Deal and the COVID-19 pandemic on the connectedness among carbon, stock, and renewable energy markets by employing Time Varying Parameter -Vector Auto Regression (TVP-VAR). First, equal interval impulse response analysis shows that in the short term, the renewable energy market suffers from a positive shock from the carbon market and this shock gradually decreases from the initial 1.6×10−3. In the long run, the connectivity between the carbon market and the stock market, and between the carbon market and the renewable energy market is almost 0. Second, we can conclude that the positive connectivity between stock market to carbon market and renewable energy market to carbon market is enhanced by COVID-19 in the short term, with values of 7.5×10−3 and 3.6×10−3 respectively. Finally, renewable energy market received a greater negative impact from the carbon market during COVID-19 than during the release of the European Green Deal, while Brexit allowed positive carbon price spillover to renewable energy price. © 2023 Elsevier Ltd

5.
Systems ; 11(4):185, 2023.
Article in English | ProQuest Central | ID: covidwho-2296867

ABSTRACT

The goal of this study is to examine and identify the factors influencing customer attitude toward and intention to use digital wallets (electronic wallets, e-wallets) during and after the COVID-19 pandemic. A total of 257 correctly fulfilled questionnaires from an online survey were summarized. The main features of e-wallet payment systems were classified with a focus on consumer satisfaction via the integration of classic and modern data analysis methods. Structural Equation Modeling (SEM) was preferred to reveal the dependencies between the variables from e-wallets users' perspective. The designed model can discover and explain the underlying relationships that determine the e-wallets' adoption mechanism. The obtained results lead to specific recommendations to stakeholders in the value chain of payment processing. Financial regulatory authorities could employ the presented results in planning the development of payment systems. E-commerce marketers could utilize the proposed methodology to assess, compare and select an alternative way for order payment. E-wallet service providers could establish a reliable multi-criteria system for the evaluation of digital wallet adoption. Being aware of the most important components of e-wallets value, managers can more effectively run and control payment platforms, enhance customer experience, and thus improve the company's competitiveness. As the perceived value of customer satisfaction is subjective and dynamic, measurements and data analysis should be conducted periodically.

6.
Energies ; 16(5), 2023.
Article in English | Scopus | ID: covidwho-2272430

ABSTRACT

We analyze crude oil's dependence and the risk spillover effect on the Chinese stock market and the gold market. We compare both static and dynamic copula functions and calculate the average upward and downward spillover effect using the time-varying Copula model and the conditional value-at-risk approach. By utilizing daily data on crude oil prices, China's stock market, and the gold market, we observe an asymmetric spillover effect: the downside spillover effects from crude oil prices on the Chinese stock market and gold market are larger than the upside spillover effect. We then identify changes in the structure of the sample periods and calculate the dynamic conditional correlation between them. In addition, we explore the optimal weight and hedge ratios in diversified portfolios to mitigate potential risks. Our results suggest that investors and portfolio managers should frequently adjust their portfolio strategies, particularly during extreme events like COVID-19, when financial assets become more volatile. Furthermore, crude oil can help reduce the risk in the Chinese stock market and gold market to some extent during different sub-periods. © 2023 by the authors.

7.
Resources Policy ; 82, 2023.
Article in English | Scopus | ID: covidwho-2272315

ABSTRACT

This paper presents a unique time-varying parameter vector autoregression (TVP-VAR) based extended joint connectedness approach to quantify the connectedness and transmission mechanism of shocks of nine commodities futures returns (namely;Gold and Silver from the category of precious metals;Copper, Lead, Zinc, Nickel and Aluminium from the category of base or industry metals;Natural Gas and Brent Crude Oil from energy sector) obtained from Multi Commodity Exchange of India Limited (MCX) from January 1, 2018 to December 31, 2021. This paper employs Balcilar et al. (2021)'s TVP-VAR extended joint connectedness approach, which combines the TVP-VAR connectedness approach of Antonakakis et al. (2020) with the joint spillover approach of Lastrapes and Wiesen (2021), to investigate the dynamic connectedness among the select commodity futures of interest. Our findings show that system-wide dynamic connectedness varies over time and is driven by economic events. The pandemic shocks appear to have an impact on system-wide dynamic connectedness, which peaks during the COVID-19 pandemic. Crude oil and zinc are the primary net shock transmitters, whereas gold and silver are the primary net shock receivers. We also discovered that the role of aluminum in shock transmitters and shock receivers changed during the course of the investigation. Pairwise connectivity, on the other hand, shows that Zinc, Copper, Nickel, and Crude oil are the key drivers of gold price changes, explaining the network's high degree of interconnectivity. During the study period, it was also discovered that silver has a significant influence on gold. Furthermore, in comparison to natural gas, gold's spillover activity is still relatively modest (on a scale), indicating that gold is less sensitive to market innovations. © 2023 Elsevier Ltd

8.
Sustainability ; 15(3):2673, 2023.
Article in English | ProQuest Central | ID: covidwho-2254687

ABSTRACT

This study aimed to examine the impact of services development and technological innovation on the embedded location of the agricultural global value chain (GVC), and the interaction between the two in fifty-seven countries (regions) around the world. This study constructed an econometric model for empirical testing based on theoretical analysis. The results showed that services development and technological innovation contributed to the embedded location of the agricultural GVC, and there was a significant substitution effect between them. A sub-group test for different income levels showed that the influence of services development and technological innovation on the embedded location of the agricultural GVC was positive in high-income and upper-middle-income countries (regions), while their influence on the embedded location of the agricultural GVC was negative in lower-middle-income countries (regions). A significant substitution effect between services development and technological innovation is always present. Quantile regression results showed that the influence of services development on the embedded location of the agricultural GVC was significantly positive at all quantile points, but the significant influence of technological innovation and the interaction between the two on the embedded location of the agricultural GVC was mainly concentrated in the low and middle quantile points. From the perspective of services development and technological innovation, this study applied the analysis framework and research methods of the global value chain to the analysis of the global agricultural value chain, expanded the research scope of the global value chain, and provided a theoretical basis for countries (regions) to further deepen their agricultural global production network and agricultural GVC.

9.
IEEE Transactions on Education ; : 1-9, 2023.
Article in English | Scopus | ID: covidwho-2250011

ABSTRACT

Contribution: The study provides empirical evidence and a deeper understanding of COVID-19’s impact on first-year engineering (FYE) students’learning experiences and motivation while accounting for gender and race/ethnicity-based variations. Background: In the Spring 2020, the COVID-19 pandemic forced campuses to close and shift unexpectedly to emergency remote instruction. These rapid transitions impacted all students, including FYE students. Research Questions: Based on the importance of the first-year experience of engineering students, this study investigated two research questions: 1) How does the rapid transition to emergency remote instruction affect FYE students’learning experiences? and 2) How do students’learning experiences during the pandemic relate to their motivation (self-efficacy and task value)? Methodology: A multimethod approach is used to investigate students’experiences on two dimensions: 1) engagement, learning, effort, concentration, interest, and interactions and 2) time management, study settings, and resources, by using ANOVA, regression models, and structural equation modeling (SEM). Results: Students who reported increased value of learning experiences reported higher self-efficacy and task value. Also, the results indicated that international students reported increased learning of new concepts, concentration in the class, interactions with instructors, and higher self-efficacy, while White and Asian students reported higher task value and availability of resources. IEEE

10.
Carbon Management ; 14(1), 2023.
Article in English | Scopus | ID: covidwho-2263698

ABSTRACT

By identifying the connectedness of seven indicators from January 1, 2019, to June 13, 2022, we choose an extended joint connectedness approach to a vector autoregression model with time-varying parameter (TVP-VAR) to analyze interlinkages between Crypto Volatility (CV) and Energy Volatility (EV). Our findings show that the COVID-19 outbreak seems to have an impact on the dynamic connectedness of the whole system, which peaks at about 60% toward the end of 2019. According to net total directional connectedness over a quantile, throughout the 2020–2022 timeframe, natural gas and crude oil are net shock transmitters, while the CV, clean energy, solar energy, and green bonds consistently receive all other indicators. Specifically, pairwise connectedness indicates that the CV appears to be a net transmitter of shocks to all energy indicators before the COVID-19 outbreak but acts as a net receiver of shocks from clean energy, wind energy, and green bonds in late 2020. The CV mostly has spillover effects on green bonds. The primary net transmitter of shocks to the Crypto market is crude oil. Our findings are critical in helping investors and authorities design the most effective policies to lessen the vulnerabilities of these indicators and reduce the spread of risk or uncertainty. © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

11.
Renewable Energy ; 202:289-309, 2023.
Article in English | Scopus | ID: covidwho-2246292

ABSTRACT

Understanding the interactions among climate change, carbon emission allowance trading, crude oil and renewable energy stock markets, especially the role of climate change in this system is of great significance for policy makers, energy producers/consumers and relevant investors. The present paper aims to quantify the time-varying connectedness effects among the four factors by using the TVP-VAR based extensions of both time- and frequency-domain connectedness index measurements proposed by Antonakakis et al. (2020) and Ellington and Barunik (2021) [8,48]. The empirical results suggest that, firstly, the average total connectedness among climate change, carbon emission allowance trading, crude oil and renewable energy stock markets is not so strong for the heterogenous fundamentals underlying them. Nevertheless, the time-varying total connectedness fluctuates fiercely through May 2005 to September 2021, varying from about 8% to 30% and rocket to very high levels during the global subprime mortgage crisis and the COVID-19 pandemic. Furthermore, the total connectedness mainly centers on the short-term frequency, i.e., 1–3 months. Secondly, climate change is generally the leading information contributor among the four factors, although not particularly strong, and its leading role also performs mainly on the short-term frequency (1–3 months). Thirdly, renewable energy stock market and crude oil market show tight interactions between them and they are the two major bridges of information exchanges across various time frequencies (horizons) in this system. Finally, we confirm the evidence that the primary net connectedness contributor and receiver switch frequently across different time frequencies, implying that it is extremely essential for policy makers, energy producers/consumers and investors to make time-horizon-specific regulatory, production/purchasing or investment decisions when facing the uncertain effects of climate change on the interactions among carbon emission allowance, crude oil and renewable energy stock markets. © 2022 Elsevier Ltd

12.
Technovation ; 120, 2023.
Article in English | Scopus | ID: covidwho-2245344

ABSTRACT

We investigate the dynamic connectedness among health-tech equity and medicine prices (producer and consumer) and Medicare cost indices for the US market. In doing so, we apply Cross-Quantilogram Dynamic Connectedness based on Time-Varying Parameter Vector Autoregression (TVP-VAR) approaches to analyse historical high-frequency time-series data. TVP-VAR results show that health-tech equity is the highest volatility transmitter while Medicare price is the highest volatility receiver. We also find medicine producer price is the net volatility contributor while the retail price of medicine is the net volatility receiver. The Cross-Quantilogram analysis confirms a strong bivariate quantile dependence between respective markets at a higher quantile of each market. Cross-quantilogram demonstrates a higher level of connectedness among the markets when considering medium and long memory. We observe health-tech equity turned to be a profound volatility contributor, while medicine price (both producer and retail prices) and Medicare appeared to net volatility receiver during the time of COVID19 Pandemic. The financial performance of health-tech equity returns elevates the price volatility of medicine and eventually Medicare cost, which imply that equity return should be incorporated forming medicine prices. © 2022 Elsevier Ltd

13.
Energy Economics ; 119, 2023.
Article in English | Scopus | ID: covidwho-2242701

ABSTRACT

The paper investigates the volatility spillover across China's carbon emission trading (CET) markets using the connectedness method based on the quantile VAR framework. The non-linear result shows strong volatility spillover effects in upper quantiles, resulting from major economic and political events. This is in accordance with the risk contagion hypothesis that volatility of carbon price returns is affected by the shocks of economic fundamentals and spills over to other pilots. Guangdong and Shanghai are the most significant contributors to volatility transmission because of their high liquidity and active markets. Hubei CET pilot has shifted from transmitter to receiver since the COVID-19 pandemic. Regarding the pairwise directional connectedness, geographical location and similar market attribute also matter in volatility transmission. This provides implications for policymakers and investors to attach importance to risk management given the quantile-based method rather than the average shocks. © 2023 Elsevier B.V.

14.
Energy Economics ; 117, 2023.
Article in English | Scopus | ID: covidwho-2242535

ABSTRACT

This study investigates the impacts of crude oil-market-specific fundamental factors and financial indicators on the realized volatility of West Texas Intermediate (WTI) crude oil price. A time-varying parameter vector autoregression model with stochastic volatility (TVP-VAR-SV) is applied to weekly data series spanning January 2008 to October 2021. It is found that the WTI oil price volatility responds positively to a shock in oil production, oil inventories, the US dollar index, and VIX but negatively to a shock in the US economic activity. The response to the EPU index was initially positive and then turned slightly negative before fading away. The VIX index has the most significant effect. Furthermore, the time-varying nature of the response of the WTI realized oil price volatility is evident. Extreme effects materialize during economic recessions and crises, especially during the COVID-19 pandemic. The findings can improve our understanding of the time-varying nature and determinants of WTI oil price volatility. © 2022

15.
Lecture Notes in Civil Engineering ; 260:271-281, 2023.
Article in English | Scopus | ID: covidwho-2241828

ABSTRACT

Earned Value Analysis is a methodology used to monitor project performance in terms of time, scope and cost and also to deal with uncertain situations that come within. Uncertainty is a part of construction project and sometimes these situations can cause a great loss in the project's success. Recently, to deal with uncertain situations a different approach has been developed to predict the project performance in a non-deterministic way, i.e., using gray interval numbers. A framework using gray interval numbers has been developed to predict the project performance and hence this study aims at using the framework to predict the performance of a real-life highway project of total duration of approximately 2 years. The analysis involves the verbal directed data from the site by the experts which were denoted as gray interval numbers. The results indicate that the project is under budget as the CPI is 1.06 and ahead of schedule as the SPI is 1.2. The results also show the worst case scenario that the project may exceed the budget as CPI is 0.83 and may run behind the schedule as SPI is 0.69. The outcomes of the study are in the form of range which provides the overall profile of the project and also helps the project team members to not always be accurate or deterministic with the outcomes. Since the construction sector was majorly hit by an uncertain event, i.e., COVID-19, this study can be very helpful in determining the performance after facing such a huge gap. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

16.
9th International Conference on Information Technology and Quantitative Management, ITQM 2022 ; 214:149-155, 2022.
Article in English | Scopus | ID: covidwho-2182429

ABSTRACT

BSE GREENEX is one of its kind indices that assesses the listed stocks on their "carbon performance"to quantify the energy efficiency of those listed stocks based on publicly available data. Past studies have analyzed the performance of listed stock of the index but not the performance of index itself. The present study analyzes the BSE GREENEX performance. The performance has also been analyzed for pre and post covid era. The result suggests that there is consistency in return over the period of time, whereas post covid performance of index is better than that of pre covid. As post covid return outperform the pre covid return, the study concludes that including sustainable finance not only attract more profit but also brings stability to the financial market and economy as well. © 2022 The Authors. Published by Elsevier B.V.

17.
Journal of Forecasting ; 2022.
Article in English | Scopus | ID: covidwho-2148304

ABSTRACT

Several procedures to forecast daily risk measures in cryptocurrency markets have been recently implemented in the literature. Among them, long-memory processes, procedures taking into account the presence of extreme observations, procedures that include more than a single regime, and quantile regression-based models have performed substantially better than standard methods in terms of forecasting risk measures. Those procedures are revisited in this paper, and their value at risk and expected shortfall forecasting performance are evaluated using recent Bitcoin and Ethereum data that include periods of turbulence due to the COVID-19 pandemic, the third halving of Bitcoin, and the Lexia class action. Additionally, in order to mitigate the influence of model misspecification and enhance the forecasting performance obtained by individual models, we evaluate the use of several forecast combining strategies. Our results, based on a comprehensive backtesting exercise, reveal that, for Bitcoin, there is no single procedure outperforming all other models, but for Ethereum, there is evidence showing that the GAS model is a suitable alternative for forecasting both risk measures. We found that the combining methods were not able to outperform the better of the individual models. © 2022 John Wiley & Sons Ltd.

18.
2022 IEEE Region 10 Symposium, TENSYMP 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2052090

ABSTRACT

Accurate forecasting of Covid-19 case load is essential to ensure healthcare system preparedness in all countries due to highly infectious strains like Omicron. Although many countries have started vaccination drives, forecasting of case numbers predominantly hasn't accounted for vaccinations. This paper investigates whether multivariate models that include vaccinations as a factor such as VAR, VARIMA and Multivariate LSTM, perform better than their univariate counterparts AR, ARIMA and Univariate LSTM, at forecasting daily case numbers. Both long-term and short-term forecast accuracies of the models have been compared using the RMSE, MAE and MAPE metrics. This study is conducted in the context of cases and vaccinations in India and USA up to January 2022 to find out the relative effect of the rate of vaccination on case load and contrast the situations in the two countries. © 2022 IEEE.

19.
2022 International Conference on Data Science and Its Applications, ICoDSA 2022 ; : 245-250, 2022.
Article in English | Scopus | ID: covidwho-2052015

ABSTRACT

The COVID-19 pandemic has reached its 20th month in Indonesia and still damaged various sectors, particularly economy. The policies imposed by the government impacted mainly the stock price. exchange rate, and people mobility in Indonesia. However, there are limited studies that incorporate these variables in Indonesia context. Thus, this study investigates the relationship between the COVID-19 pandemic, stock price, exchange rate, and workplace mobility simultaneously. This study employs Vector Autoregressive (VAR) as the analysis considering its advantages in finding the causal relationship between variables and periodic interpretation using Impulse Response Function (IRF). The VAR results show that from the Granger Causality Test, it turns out that the shocks from COVID-19 positivity rate and mobility in workplaces caused the changes in stock price and exchange rate. On the other hand, the IRF results exhibit the depreciating responses of stock price and exchange rate due to the shocks of COVID-19 positivity rate and mobility are enormous in the short term. In the longer term, the stock price response needs a longer time to return to the initial condition than the exchange rate. Therefore, further policy evaluation and formulation become essential to maintain the stock price and exchange rate, mainly due to the effect of COVID-19 and workplace mobility. © 2022 IEEE.

20.
2022 International Conference on Cyber Security, Artificial Intelligence, and Digital Economy, CSAIDE 2022 ; 12330, 2022.
Article in English | Scopus | ID: covidwho-2029450

ABSTRACT

The outbreak of the Covid-19 caused the emergence of many related pandemic prevention policies, which evidently influenced the demand and supply sides of the agricultural products and may therefore make the relative products’ price fluctuate. This paper chooses the egg price in Henan province in China as a detailed situation to do the empirical research by using vector autoregression model (VAR), and try to find out the relationship between egg price volatility and the number of indigenous confirmed Covid-19 cases, Granger causality Wald test is also used in order to test the causal relationship between these two factors. We find that the fluctuation of egg price in Henan province was not positively related to the number of confirmed pandemic cases, but has the positive relationship with the supply of the eggs. Our findings suggest local governments should place much emphasis on ensuring stability of the supply side of the agricultural products in times of crisis. © 2022 SPIE.

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