Search Results (3)

Recent studies have investigated whether the rate of global warming has changed since the 1970s, with particular attention to the role of natural variability and its removal from temperature time series. In particular, Foster and Rahmstorf analyzed global mean surface temperature series, adjusted for natural variability. However, their procedure might produce spurious changepoints, since it does not appropriately handle the autocorrelation present in the residuals of the models considered. In this study, we revisit the same adjusted temperature series using a different methodology (the Quandt likelihood ratio test) while properly accounting for the presence of autocorrelation. We find evidence that global temperature has departed from its previous path since around 2013–2014. Our results provide robust proof of a clear recent increase in the temperature trend for adjusted time series, at a rate of warming that has doubled since that date. Full article

The Global Fear Index (GFI) is a measure of fear/panic based on the number of people infected and deaths due to COVID-19. This paper aims to examine the interconnection or interdependencies between the GFI and a set of global indexes related to the financial and economic activities associated with natural resources, raw materials, agribusiness, energy, metals, and mining, such as: the S&P Global Resource Index, the S&P Global Agribusiness Equity Index, the S&P Global Metals and Mining Index, and the S&P Global 1200 Energy Index. To this end, we first apply several common tests: Wald exponential, Wald mean, Nyblom, and Quandt Likelihood Ratio. Subsequently, we apply Granger causality using a DCC-GARCH model. Data for the global indices are daily from 3 February 2020 to 29 October 2021. The empirical results obtained show that the volatility of the GFI Granger causes the volatility of the other global indices, except for the Global Resource Index. Moreover, by considering heteroskedasticity and idiosyncratic shocks, we show that the GFI can be used to predict the co-movement of the time series of all the global indices. Additionally, we quantify the causal interdependencies between the GFI and each of the S&P global indices using Shannon and Rényi transfer entropy flow, which is comparable to Granger causality, to confirm directionality more robustly The main conclusion of this research is that financial and economic activity related to natural resources, raw materials, agribusiness, energy, metals, and mining were affected by the fear/panic caused by COVID-19 cases and deaths. Full article

Over recent decades several European and global occurrences have had an impact on the European Union’s economic sectors, and subsequently on farms. In fact, the various Common Agricultural Policy (CAP) reforms, namely those since 1992, and the global financial and economic crises, specifically after 2008, seem to have had several effects on the dynamics of the entire European Union agricultural sector and on the performance of farms. However, there is doubt as to whether these events were enough to promote structural breaks in European Union farms. In this way, the main objective of this study is to analyse both the known and unknown structural breaks in European farms, between 1989 and 2016. To this purpose, data from the Farm Accountancy Data Network (FADN) from the twelve former member-states (the countries with the longer time series) and methodologies based on the Chow test and on the Quandt likelihood ratio (QLR) were considered. The results show that the structural breaks are different across the several twelve former European Union countries and among the several variables considered. In any case, the financial and economic crises, as well as changes in the European Union’s methodologies relative to statistical information, seem to have had a greater impact on the European farms than the several CAP reforms (with the exception of the reform of 1992 the trade liberalization). However, the several consequences of all these European and world events on European farms seem to be delayed for some years. Full article