This paper investigates persistence in the MINT (Mexico, Indonesia, Nigeria, Turkey) stock markets applying fractional integration methods to daily data from 1 January 2022 to 31 October 2025. Different model specifications are estimated for prices, log prices and log returns under the...

This paper investigates persistence in the MINT (Mexico, Indonesia, Nigeria, Turkey) stock markets applying fractional integration methods to daily data from 1 January 2022 to 31 October 2025. Different model specifications are estimated for prices, log prices and log returns under the...

This paper analyses aggregated data (5 days period) on total solar irradiance (TSI) based on the 3D MHD numerical simulations of solar surface and atmosphere (Yeo et al., 2017), from 30 April 2010 to 8 July 2023. It improves upon earlier studies by including in the sample the most recent...

This paper analyses aggregated data (5 days period) on total solar irradiance (TSI) based on the 3D MHD numerical simulations of solar surface and atmosphere (Yeo et al., 2017), from 30 April 2010 to 8 July 2023. It improves upon earlier studies by including in the sample the most recent...

This paper puts forward a general statistical model in the time domain based on the concept of fractional integration. More specifically, in the proposed framework instead of imposing that the roots are strictly on the unit circle, we also allow them to be within the unit circle. This approach...

This note puts forward a new modelling approach that includes both fractional integration and autoregressive processes in a unified framework. The proposed model is very general and includes other more standard approaches such as the AR(F)IMA models. Some Monte Carlo evidence shows that the...

This paper applies fractional integration methods to obtain evidence on ocean acidification, namely the decrease in the pH level in the Earth's oceans, using the annual Hawaii Ocean Time-series Station ALOHA series as well as the logged one for the period 1985-2024. The chosen modelling...

This paper applies fractional integration methods to obtain evidence on ocean acidification, namely the decrease in the pH level in the Earth’s oceans, using the annual Hawaii Ocean Time-series Station ALOHA series as well as the logged one for the period 1985-2024. The chosen modelling...

This paper analyses trends and persistence in air pollution levels in 88 US metropolitan areas using fractional integration methods. The results indicate that the differencing parameter d is higher than 0 in 38 of the series, which supports the hypothesis of long-memory behaviour and implies...

This paper analyses trends and persistence in air pollution levels in 88 US metropolitan areas using fractional integration methods. The results indicate that the differencing parameter d is higher than 0 in 38 of the series, which supports the hypothesis of long-memory behaviour and implies...