Risk factors in oil and gas industry returns: international evidence

This paper analyzes the exposure of the oil and gas industry of 34 countries to oil prices. Using a multifactor panel model to estimate the oil and gas excess stock returns, our results strongly support the view that oil price is a globally priced factor for the oil industry. In particular, the response of the oil and gas sector to changes oil prices is positive and larger for developed countries than for emerging markets. The industry response is asymmetric, with positive oil price changes having a greater impact on the oil sector returns than negative changes. Furthermore, local market index returns, currency rates and oil price volatility also have a significant impact on oil industry's excess returns. Finally, industry local sensitivities seem to vary with stock market activity and with levels of appropriation of industry revenues by governments. Results are robust to a battery of tests.Multifactor asset pricing models, Panel Data, Oil industry

Asymmetric effects of oil price fluctuations in international stock markets

New evidence on the way oil price fluctuations affect international stock markets is provided in analysis of the exposure of 43 stock markets. Oil price spikes depress international stock markets, but oil price drops do not necessarily increase stock market returns. Moreover, the volatility of oil prices has a negative impact on international stock market returns. Both these effects apply only to stock markets of developed countries. Emerging market returns are not sensitive to oil price variations. In addition, the asymmetry of oil price changes impacts oil volatility; i.e., when oil prices soar, oil volatility also increases, while negative oil price changes dampen volatility. Finally, oil price fluctuations are a factor in creating downside risk for international country investment.Asymmetry, Multifactor asset pricing Models, Oil prices, Panel data, Quantile regression, Volatility

CORRELATIONS BETWEEN OIL AND STOCK MARKETS: A WAVELET-BASED APPROACH

In a global economy, shocks occurring in one market can spill over to other markets. This paper investigates the impact of oil shocks and stock markets crashes on correlations between stock and oil markets. We test changes in correlations at different scales with non-overlapping confidence intervals based on estimated wavelet correlations. Contrary to other approaches, this method does not need adjustment for heteroskedasticity biases on the correlation coefficients. Our results show that oil shocks affect the correlation between both markets. The evidence on the change of correlation between stock markets after an oil shock is weaker; except in some specific cases during the Kuwait war and the OPEC cutback period. Conversely, we only find weak evidence that stock market crashes change the correlation between oil and stock markets. Overall, the evidence gives support to including oil as an asset class in asset allocation strategies.he authors acknowledge financial support from Financial Research Center–UNIDE and from the Spanish Ministry of Education and Science, research projects MTM2010-17323, ECO2011-25706, ECO2012-32401 and MTM2012-36163-C06-03

Sensors & transducers measuring water quality parameters

Peer Reviewe

La influència del gènere i de l'ensenyament de les tecnologies en l'elecció professional de l'alumnat a l'ESO i el Batxillerat

Les dones patim, encara ara en ple s. XXI, la discriminació de la societat. Un dels efectes d'aquesta discriminació és el poc accés de les dones a les carreres de ciència i tecnologia. Aquest estudi pretén comprovar les teories existents sobre aquest fet en un centre de secundària de Catalunya, i reflexionar sobre com l'ensenyament de la Tecnologia pot influir per produir un canvi

The role of Portuguese companies in the development of corporate strategies: case study

Strategy assumes a significant role in the managerial field. From the primordial military setting until the managerial context, strategy is becoming increasingly noticeable due to the complexity of business context itself. It aims to define goals in order to achieve competitive advantages, sustainable in the long term. In academic terms, corporate strategy consists in a set of conceptualized strategies with distinct purposes. But how does one make a decision regarding corporate strategies? Which forces, internal or external, are capable of influencing it? Are these corporate strategies equally perceived by distinct companies? It is possible to notice a gap of perception between the academic and business settings. In academic terms, strategy is only explored towards its aim. However, under real conditions, companies are exposed to further features. As so, the present investigation aims to develop an understanding about how distinct companies perceive strategy. This study relies on data from 30 companies who operate in Portugal, with a variety of industries like, assurance, architecture, consulting, coffee production, energy food & beverages supply it/software logistics and distribution, metallurgic, online services, recruitment and retail. The results include valuable information regarding the main drivers of the decision behind corporate strategies and the dissimilarities associated to the perception of strategy at the corporate level.A estratégia é um dos tópicos de referência no campo da gestão. Do contexto militar primordial até à perspectiva empresarial nos dias de hoje, a estratégia tem uma importância crescente devido à complexidade do contexto empresarial actual. Tem como objectivo a definição de metas para atingir uma vantagem competitiva sustentável a longo prazo. Ao nível académico, existe um conjunto de estratégias já conceptualizadas, distintas no fim a que se destinam. Contudo, como é tomada a decisão relativamente à estratégia a adoptar ao nível corporativo? Que forças, internas ou externas à empresa, podem influenciar essa decisão? Terão as empresas percepções semelhantes em relação a cada uma das estratégias? Existe uma disparidade notória entre a percepção da estratégia entre o meio académico e o contexto empresarial real, em que cada empresa é um caso individual, com influências internas e externas distintas. Deste modo, a presente investigação pretende aferir sobre os factores com maior influência na tomada de decisão. Igualmente, pretende-se criar um entendimento sobre a percepção de cada uma das estratégias em diferentes organizações e os principais factores na origem de possíveis diferenças. Neste estudo, participaram 31 empresas ligadas a Portugal, de diversos sectores- Seguros, Arquitectura, Consultoria, Produção de Café, Energia, Distribuição Alimentar e Bebidas, IT/Software, Logística e Distribuição, Metalúrgica, Serviços Online, Recrutamento e Retalho.. Como resultado, atingiram-se importantes conclusões, nomeadamente no que respeita aos principais drivers da decisão estratégica na origem das estratégias corporativas e às diferenças de percepção das estratégias corporativas em diferentes empresas

Spontaneous pneumomediastinum

Pneumomediastinum is defined as the presence of air in the mediastinal cavity. Can be classified into two categories: secondary pneumomediastinum, when there is a causative etiological factor and spontaneous pneumomediastinum, without a clear etiology.info:eu-repo/semantics/publishedVersio

Asymmetric effects of oil price fluctuations in international stock markets

New evidence on the way oil price fluctuations affect international stock markets is provided in analysis of the exposure of 43 stock markets. Oil price spikes depress international stock markets, but oil price drops do not necessarily increase stock market returns. Moreover, the volatility of oil prices has a negative impact on international stock market returns. Both these effects apply only to stock markets of developed countries. Emerging market returns are not sensitive to oil price variations. In addition, the asymmetry of oil price changes impacts oil volatility; i.e., when oil prices soar, oil volatility also increases, while negative oil price changes dampen volatility. Finally, oil price fluctuations are a factor in creating downside risk for international country investment

Risk factors in oil and gas industry returns: international evidence

This paper analyzes the exposure of the oil and gas industry of 34 countries to oil prices. Using a multifactor panel model to estimate the oil and gas excess stock returns, our results strongly support the view that oil price is a globally priced factor for the oil industry. In particular, the response of the oil and gas sector to changes oil prices is positive and larger for developed countries than for emerging markets. The industry response is asymmetric, with positive oil price changes having a greater impact on the oil sector returns than negative changes. Furthermore, local market index returns, currency rates and oil price volatility also have a significant impact on oil industry's excess returns. Finally, industry local sensitivities seem to vary with stock market activity and with levels of appropriation of industry revenues by governments. Results are robust to a battery of tests

Conductivity cell for water quality monitoring

The measurement of electrolytic conductivity is widely applied as a control parameter and its relevance is continously increasing, not only in industrial applications but also in the environmental monitoring domain. In this work the attention is focused on the electrical behaviour of a low cost in-situ four electrode conductivity sensor for water quality monitoring in estuaries and oceans. The design of the sensor, the method used to determine the conductivity value, the circuit developed for signal conditioning and the data acquisition board that links the sensor to the computer for further signal processing are described in detail. The output values of the conditioning circuit are stored in the computer and compared with more accurate conductivity values obtained from commercial equipment. In order to obtain more accurate results algorithms for digital signal processing have been presented and implemented.Peer Reviewe