http://hdl.handle.net/10071/5776 2026-04-05T13:02:26Z 2026-04-05T13:02:26Z Martins, L. F. Clemente-Casinhas, L. Ferreira-Lopes, A. http://hdl.handle.net/10071/32230 2025-03-28T13:05:21Z 2024-01-01T00:00:00Z

Título próprio: Uncovering the (possible) relationship between Central Bank Independence and economic growth in the context of monetary unions Autoria: Martins, L. F.; Clemente-Casinhas, L.; Ferreira-Lopes, A. Resumo: This work estimates the relationship between Central Bank Independence (CBI) and economic growth in the context of monetary unions, using dynamic panel models. We use two measures of CBI: the Legal CBI index and the irregular turnover rate. When an irregular turnover of the Central Bank Governor occurs, it harms growth for countries outside monetary unions. On the contrary, the Legal CBI index is a positive factor for growth, although only regarding countries belonging to monetary unions. The limitations on lending to the government is the most important component of the Legal CBI, which explains this result. Additionally, we analyse sub-samples taking into account the level of income, the number of crises, the existence of quantitative easing policies, and different time windows. Interestingly, 1990–2013 was a harmful period for growth for the entire sample but benign for countries that belong to monetary unions. Moreover, when countries are in a crisis they benefit from being a member of a monetary union with an independent central bank. Results seem to point to the conclusion that Legal CBI in a monetary union has the potential to increase economic growth rates.

2024-01-01T00:00:00Z Mesquita, C. Carvalho, M. http://hdl.handle.net/10071/31363 2024-11-29T11:56:02Z 2024-01-01T00:00:00Z

Título próprio: The carbon footprint of common vegetarian and non-vegetarian meals in Portugal: An estimate, comparison, and analysis Autoria: Mesquita, C.; Carvalho, M. Resumo: Purpose: Vegetarian diets have been suggested as one way to reduce the carbon footprint of individuals, when compared to standard Western diets, given the latter’s inclusion of high-carbon footprint animal foods. However, it is unclear if, within usually consumed meals, the average vegetarian meals have a significantly lower carbon footprint than non-vegetarian meals. Often consumed meals were designated as “common” in this research and obtained from real consumers’ food diaries. The purpose of this research is to find out if, in Portugal, common vegetarian meals have a lower carbon footprint than common non-vegetarian meals; and, to communicate the results in a format that might lead consumers in Portugal to reduce this food carbon footprint of theirs. Methods: We conducted a novel analysis for Portugal, namely due to three factors: (1) its focus on meals, rather than ingredients; (2) the inclusion of national food consumption, rather than food production; and (3) presenting the results in a traffic light system. It was also tested how non-vegetarian meals’ carbon footprint would change if animal protein was replaced by plant protein. Results: The carbon footprint of common non-vegetarian meals in Portugal is 5.5 times higher than that of common vegetarian meals in Portugal. There is a wide range of carbon footprint values for vegetarian meals in Portugal, specifically, the 5th percentile is 8.5 times smaller than the 95th percentile. Moreover, the common non-vegetarian meals in Portugal when “made” vegetarian have a carbon footprint about 6.4 times lower than the common non-vegetarian meals in Portugal. Conclusions: There are known limitations in this research, besides the unknown ones, such as using only one environmental impact indicator, namely the carbon footprint (rather than the ecological footprint, other, or even none of these); the limited breadth of studies selected, to obtain the food items’ carbon footprint (reviews, meta-studies, and local studies); and the narrow LCA boundaries and characteristics included in those and subsequent analysis (of the food items’ bioavailability and nutritional functional unit, among others). However, within the scope of this research, the three general hypotheses of this research have been confirmed. It can be concluded that vegetarian food is a potential solution for food’s environmental sustainability in Portugal.

2024-01-01T00:00:00Z Pratas, T. E. Ramos, F. R. Rubio, L. J. http://hdl.handle.net/10071/28946 2023-07-05T16:59:25Z 2023-01-01T00:00:00Z

Título próprio: Forecasting bitcoin volatility: Exploring the potential of deep learning Autoria: Pratas, T. E.; Ramos, F. R.; Rubio, L. J. Resumo: This study aims to evaluate forecasting properties of classic methodologies (ARCH and GARCH models) in comparison with deep learning methodologies (MLP, RNN, and LSTM architectures) for predicting Bitcoin's volatility. As a new asset class with unique characteristics, Bitcoin's high volatility and structural breaks make forecasting challenging. Based on 2753 observations from 08-09-2014 to 01-05-2022, this study focuses on Bitcoin logarithmic returns. Results show that deep learning methodologies have advantages in terms of forecast quality, although significant computational costs are required. Although both MLP and RNN models produce smoother forecasts with less fluctuation, they fail to capture large spikes. The LSTM architecture, on the other hand, reacts strongly to such movements and tries to adjust its forecast accordingly. To compare forecasting accuracy at different horizons MAPE, MAE metrics are used. Diebold-Mariano tests were conducted to compare the forecast, confirming the superiority of deep learning methodologies. Overall, this study suggests that deep learning methodologies could provide a promising tool for forecasting Bitcoin returns (and therefore volatility), especially for short-term horizons.

2023-01-01T00:00:00Z Gasteiger, E. Prettner, K. http://hdl.handle.net/10071/22007 2022-04-08T04:11:12Z 2022-01-01T00:00:00Z

Título próprio: Automation, stagnation, and the implications of a robot tax Autoria: Gasteiger, E.; Prettner, K. Resumo: We assess the long-run growth effects of automation in the overlapping generations framework. Although automation implies constant returns to capital and, thus, an AK production side of the economy, positive long-run growth does not emerge. The reason is that automation suppresses wage income, which is the only source of investment in the overlapping generations model. Our result stands in sharp contrast to the representative agent setting with automation, where sustained long-run growth is possible even without technological progress. Our analysis therefore provides a cautionary tale that the underlying modeling structure of saving/investment decisions matters for the derived economic impact of automation. In addition, we show that a robot tax has the potential to raise per capita output and welfare at the steady state. However, it cannot induce a takeoff toward positive long-run growth.

2022-01-01T00:00:00Z