Suchergebnisse

AbstractThe main aim of this paper is to present a Bayesian analysis of Multivariate GARCH(l, m) (M-GARCH) models including estimation of the coefficient parameters as well as the model order, by combining a set of existing MCMC algorithms in the literature. The proposed algorithm focuses on the BEKK formulation of the multivariate GARCH model. The estimation procedure will be designed as a custom MCMC with embedded Reversible Jump MCMC (RJMCMC) and Delayed Rejection Metropolis-Hastings (DRMH) steps implemented using the statistical software R. The RJMCMC steps allow three variants of BEKK models (constant, diagonal and full) to be indexed and this index included as a parameter to be estimated. The proposed MCMC algorithms are validated using extensive simulation experiments followed by a case study using bivariate data derived from the daily share prices for BHP Group Limited, Rio Tinto Group, and Fortescue Metals Group Limited on the ASX over from September 2013 to December 2021.

AbstractThis study examines the mean and variance spillovers between patents filed and total factor productivity in Pakistan during the period lasting from 1964 to 2015. Using the multivariate generalized autoregressive conditionally heteroskedastic–Baba, Engle, Kraft and Kroner (GARCH–BEKK) model, we find no evidence of mean spillover effects between patents filed and productivity growth. However, the results support the existence of the variance spillover effect, which illustrates that the innovations may affect productivity in the long‐run. Moreover, bidirectional causality in the mean and variance between innovation and productivity growth is non‐existent. We find that R&D/GDP, skilled labour force and economic freedom are the significant factors affecting technological advancements in the country. We also determine that R&D/GDP and economic freedom are the important factors affecting patent activities in Pakistan. Our findings suggest that the government needs to emphasize the regulations of the patent system to safeguard the interests of investors, which ultimately promotes economic growth.

Dynamic hedging effectiveness for soybean farmers in Rondonópolis (MT) with futures contracts of BM&F-BOVESPA is calculated through optimal hedge determination, using the bivariate GARCH BEKK model, which considers the conditional correlations of the prices series, comparing the results with the minimum variance model effectiveness, calculated by OLS, the unhedged and the naïve hedge positions. The financial effectiveness of the dynamic hedge model is superior and can be used by farmers for several decision making purposes such as price discovery, hedging calibration, cash flow projections, market timing, among others.

Purpose
This paper aims to investigate the effects of volatility transmission among Bitcoin and other leading cryptocurrencies, namely, Binance USD, BNB, Cardano, Dogecoin, Ethereum, Polkadot, Polygon, Solana, Tether, USD Coin and XRP.


Design/methodology/approach
The multivariate BEKK-GARCH model is used with the daily data set from 1 January 2017 to 31 March 2023. The data set is analysed in its entirety and is also the COVID-19 epidemic period.


Findings
The study reveals that while the volatility of cryptocurrency prices is influenced by their own historical shocks and volatility, there is proof of the effects shock transmission among Bitcoin and other notable cryptocurrencies. Furthermore, the authors identify the spillover effects of volatility among all 11 pairs and provide evidence that conditional correlations with varying time constants are present, and predominantly positive for both the entire and COVID-19 outbreak periods.


Practical implications
The findings will be helpful to market experts who want to avoid losses in traditional assets. To develop the best risk management and hedging strategies, businesses might use the information to build asset portfolios or personalise payment methods. The use of such data by investors and portfolio managers could aid in the development of investment opportunities, risk insurance plans or hedging strategies for the management of financial portfolios.


Originality/value
To the best of the authors' knowledge, the use of the BEKK-GARCH model for examining the effects of volatility spillover among Bitcoin and the other eleven top cryptocurrencies has not been previously documented.