Why has Growth slowed in Sub-Saharan Africa: A System GMM-IV Approach

In this paper we estimated the traditional cross-country growth model and corrected for model endogeneity bias and country-specific hetereogeneity effects. Using the System-IV Generalized Method of Moments (GMM) approach, we identified the key factors that determine GDP per capita growth rate in a panel regression model of 100 countries. Parameter robustness tests was applied to the models which also included: Within Fixed E®ects; Pooled-Ordinary Least Square and Levels-IV GMM models, using the Extreme Bounds Analysis (EBA). We found that most of the estimated covariates that show significant coefficients in the regression model are actually fragile, except for initial income, institutions and real exchange rate over valuation. More importantly too, the results suggested that natural resource endowment, such as oil, may not have accounted for why some resource rich developing countries (e.g Nigeria) have grown slowly as is commonly argued in the literature.Fixed Effects Models; Economic Growth; Endogeneity; Method of Moments

Oil Price Shocks and Monetary Policy Aggregates in Nigeria: A Structural VAR Approach

Studies have shown that the impact of oil price volatility varies significantly across countries and within the different sectors of a particular economy. The impact vary according to the prevailing state of an economy: whether the economy is a net importer or exporter of oil; the exchange rate regime; monetary policy framework; the vulnerability of the key sectors of the economy and the degree of openness of the economy. In this study, we have used both restricted and unrestricted structural VAR models to decompose the impact of oil price shocks. Using a seven-variable VAR matrix which include monetary policy aggregates, we forecast the impact of a one standard deviation innovation to oil price on inflation rate, money supply, interest rate, government expenditure, GDP per capita growth rate, exchange rate and manufacturing output over a ten-year period. We imposed identification restrictions on the VAR model to identify the structural parameters of the seven equations and show the variance decomposition analysis. The results shows that the second-round effects of oil price shocks may be transmitted to the other sectors of the economy through the government expenditure - inflation rate channels with significant direct impact on the real sector and other monetary aggregates.Oil Price Shocks; Monetary Policy; Vector autoregressive model

Linking dissolved organic matter quality and quantity to CO2 and CH4 concentrations in ombrotrophic bog pools

Les petits plans d'eau, en particulier ceux riches en matière organique, sont encore négligés en tant que sources naturelles majeures d'émission de carbone (C) dans l'atmosphère et contributeurs importants au bilan mondial de C. Les mares de tourbières riches en matières organiques sont une source nette de C atmosphérique dans les écosystèmes de tourbières, qui sont généralement un puits net de C. Ces mares émettent des gaz à effet de serre (GES) à des taux plus élevés, en particulier de méthane (CH4), par rapport à d'autres petits plans d'eau lentiques (petits lacs et étangs), ce qui peut être attribué à la connectivité hydraulique des bassins donc aux apports en C de la tourbe environnante et aux caractéristiques morphologiques des mares. Cependant, il existe très peu d'informations sur les schémas et les mécanismes de la dynamique du C dans les bassins de tourbières par rapport à leur couvert végétal ainsi qu'à d'autres petits environnements aquatiques. En particulier, la matière organique dissoute (MOD), un important intermédiaire et substrat de C, peut influencer la dynamique des émissions de GES, mais son rôle demeure méconnu à l'échelle intra- et inter-régionale. Dans cette étude, nous avons caractérisé et identifié les patrons intra- et interrégionaux et les mécanismes potentiels contrôlant la quantité et la qualité de la MOD et des concentrations de GES, ainsi que leurs liens en analysant une gamme de variables optiques et chimiques et en compilant les données géographiques (c'est-à-dire le climat, le couvert végétal et morphométrie des bassins) à partir de bassins de tourbières ombrotrophes dans cinq régions de l'est du Canada (Grande plée Bleue, sud du Québec et région de la Minganie, est du Québec) et du sud de la Patagonie chilienne (Punta Arenas, parc Karukinka et île Navarino). Nous avons également effectué un échantillonnage interannuel dans la Grande plée Bleue pour identifier les tendances temporelles des concentrations et de la composition des GES et de MOD. Nous avons trouvé une variabilité interrégionale élevée dans les patrons de MOD et de GES par rapport à la variabilité intrarégionale qui était cohérente avec l'hétérogénéité des propriétés géographiques, en particulier, le climat. Les patrons interrégionaux des concentrations de GES étaient de plus déterminés par la couverture végétale environnante, la morphométrie du bassin et la composition de la MOD de type protéique. D'autre part, bien que nous n'ayons pas observé de patrons temporels significatifs dans les concentrations de GES, de MOD et de la composition de type humique terrestre au cours de l’été dans la Grande plée Bleue, les patrons temporels de GES ont été influencés par la concentration de MOD, la composition de type humique terrestre, et la chimie interne de l'eau. Dans l'ensemble, nos résultats suggèrent que les patrons interrégionaux de la MOD et des GES, et les liens entre eux, sont principalement contrôlés par le climat (température et précipitations), la couverture végétale et la morphométrie des bassins, tandis que les patrons temporels de la MOD et des GES sont principalement régis par des facteurs à l'échelle locale tels que la morphométrie des bassins et la connectivité hydrologique.Small waterbodies, especially organic-rich, are still overlooked as a major natural source of carbon (C) emission to the atmosphere and an important contributor in the global C budget. Organic-rich peatland pools are generally net atmospheric C sources embedded in peatland ecosystems, which are generally net C sinks. They emit high areal rates of greenhouse gases (GHG), particularly methane (CH4), compared to other small lentic waterbodies (small lakes and ponds) which may be attributed to peat-pool hydraulic connectivity leading to C loading from the surrounding peat and morphological characteristics. But there is very little information on the patterns and drivers of C dynamics within peatland pools compared to their vegetated areas as well as other small aquatic environments. In particular, the role that dissolved organic matter (DOM), an important intermediate and C substrate, may play in GHG dynamics is poorly known at the intra- and inter-regional scales. In this study, we characterized and identified the intra- and inter regional patterns and drivers of DOM quantity and quality and GHG concentrations as well as their links. We did so by analyzing a range of optical and chemical variables and compiling geographic data (i.e., climate, vegetation cover and pool morphometry) from ombrotrophic peatland pools across five regions in eastern Canada (Grande plée Bleue, southern Québec and Minganie region, eastern Québec) and southern Chilean Patagonia (Punta Arenas, Karukinka Park and Navarino Island). We also conducted inter-annual sampling in Grande plée Bleue to identify the temporal patterns in GHG and DOM concentrations and composition. We found high inter-regional variability in DOM and GHG patterns compared to intra-regional variability which was coherent with the heterogeneity of geographical properties. Inter-regional patterns in GHG concentrations were driven by surrounding vegetation cover, pool morphometry and protein-like DOM composition. On the other hand, although we did not observe significant temporal patterns in GHG and DOM concentrations and terrestrial humic-like composition throughout the growing seasons in Grande plée Bleue, temporal patterns of GHG were influenced by the DOM concentration, terrestrial humic-like composition, and internal water chemistry. Overall, our results suggest that inter-regional patterns in DOM and GHG, and the links among them are predominantly controlled by the broad-scale patterns in climate (temperature and precipitation), vegetation cover, and pool morphometry, while temporal patterns in DOM and GHG are predominantly governed by local-scale drivers such as pool morphometry

Consequences of public programs and private transfers on household’s investment in protection from natural disasters

Considering the issues of households’ accessibility to public programs and private inward remittances, there is a need to better understand the linkages through which households’ decision to pursue private defensive strategies (or private protection activities) might be influenced. This has significant policy implications especially for low-and-middle income countries vulnerable to natural disasters. We introduce a theoretical model of household private investment in protection against damages from a natural disaster event given the presence of public programs and the possibility of receiving inward remittances from members of the household

Learning motivation for slow learners with tablet technology

Vertically Aligned Carbon Nanotube arrays (also termed as VACNTs or CNT forest) have recently found to be transformable to a reflective mirror from a naturally black absorber. The feature of improved reflectance can be attained by the controllable tip bending process using the bottom surface of a rotated cylindrical tool (the process called micro-mechanical bending (M2B)). In this paper, the polarized light reflectance of bent and compacted region of the CNT forest using M2B method has been investigated. We observed that reflectance from the processed CNT zone was highly dependent on the angle of incidence and polarization state of the incident laser. For the first time, the refractive index of the tip bent CNT forests by M2B method was investigated and found to be in a range of ∼1.8

Free broadcast DGPS service in marine: how good is it?

Differential GPS (DGPS) has been used widely in many types of application including for marine navigation and hydrographic surveying. Most of the recent DGPS receiver development applies the use of code and carrier phase on single frequency L1 C/A code receiver for submetre horizontal accuracy. Differential Global Navigation Satellite System (DGNSS) radio beacon is a system that uses the concept of DGPS based on pseudorange measurements. This system provides free DGPS corrections using the commercial reference station with proper receivers. The availability of reference station that operates 24 hours a day means that the users are no longer required to set up their own reference station. This study is intended to evaluate the performance of DGNSS radio beacon, not only for horizontal positioning but also for data availability and reliability at the remote receiver. For this purpose, static and dynamic test have been carried out on the DGPS corrections received from DGNSS radio beacon. Both of the tests make use of the National Marine Electronic Associations 0183 (NMEA 0183) data format generate by remote receiver to examine the DGPS broadcast signal. The results show how the distance separation (static test) effects the age of DGPS correction, horizontal dilution of precision (HDOP), numbers of satellite use and also the signal strength recorded at remote receiver. Meanwhile, the tracking method (dynamic test) differentiates the automatic and manual tracking results. This is to estimate the most suitable method to be used for marine navigation and hydrographic surveys

Analyzing the determinants of farmers' choice of adaptation methods and perceptions of climate change in the Nile Basin of Ethiopia:

"This study identifies the major methods used by farmers to adapt to climate change in the Nile Basin of Ethiopia, the factors that affect their choice of method, and the barriers to adaptation. The methods identified include use of different crop varieties, tree planting, soil conservation, early and late planting, and irrigation. Results from the discrete choice model employed indicate that the level of education, gender, age, and wealth of the head of household; access to extension and credit; information on climate, social capital, agroecological settings, and temperature all influence farmers' choices. The main barriers include lack of information on adaptation methods and financial constraints. Moreover, the analysis reveals that age of the household head, wealth, information on climate change, social capital, and agroecological settings have significant effects on farmers' perceptions of climate change." from authors' abstractAdaptation, Perception on climate change, Agriculture, Climate change, Nile Basin of Ethiopia,

Why has Growth slowed in Sub-Saharan Africa: A System GMM-IV Approach

In this paper we estimated the traditional cross-country growth model and corrected for model endogeneity bias and country-specific hetereogeneity effects. Using the System-IV Generalized Method of Moments (GMM) approach, we identified the key factors that determine GDP per capita growth rate in a panel regression model of 100 countries. Parameter robustness tests was applied to the models which also included: Within Fixed E®ects; Pooled-Ordinary Least Square and Levels-IV GMM models, using the Extreme Bounds Analysis (EBA). We found that most of the estimated covariates that show significant coefficients in the regression model are actually fragile, except for initial income, institutions and real exchange rate over valuation. More importantly too, the results suggested that natural resource endowment, such as oil, may not have accounted for why some resource rich developing countries (e.g Nigeria) have grown slowly as is commonly argued in the literature