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201.
Federico Galán-Valdivieso Elena Villar-Rubio María-Dolores Huete-Morales 《International Environmental Agreements: Politics, Law and Economics》2018,18(5):689-706
The Kyoto Protocol envisages the use of various instruments to achieve emission reduction targets, one of which is the European Union Emission Trading Scheme (EU ETS), the most important market worldwide for CO2 emission allowances. The volume of European Union Allowances traded represents over 45% of all the carbon dioxide generated by human activity within the continent. In its first two phases (2005–2012), the behaviour of the EU ETS was erratic, as a result of discretionary policies, an oversupply of allowances and reduced economic activity due to the global crisis. These factors caused excessively low prices that distorted the initial goals of achieving low-carbon solutions. From 2013, changes were made to the market regulation mechanisms in order to correct these structural deficiencies. Empirical analysis of daily prices in the two central phases of the market, following the pattern of ARCH and GARCH models, shows that the measures taken within the EU generated greater confidence and stability in the market and thus reduced volatility. Subsequent price behaviour, following a bullish path, has confirmed the success of the measures taken and their contribution to fulfilling emission reduction targets. 相似文献
202.
Eric Bettinger Robert Fairlie Anastasia Kapuza Elena Kardanova Prashant Loyalka Andrey Zakharov 《Journal of policy analysis and management》2023,42(2):552-570
The previous expansion of EdTech as a substitute for traditional learning around the world, the recent full-scale substitution due to COVID-19, and potential future shifts to blended approaches suggest that it is imperative to understand input substitutability between in-person and online learning. We explore input substitutability in education by employing a novel randomized controlled trial that varies dosage of computer-assisted learning (CAL) as a substitute for traditional learning through homework. Moving from zero to a low level of CAL, we find positive substitutability of CAL for traditional learning. Moving from a lower to a higher level of CAL, substitutability changes and is either neutral or even negative. The estimates suggest that a blended approach of CAL and traditional learning is optimal. The findings have direct implications for the rapidly expanding use of educational technology worldwide prior to, during, and after the pandemic. 相似文献