This study examined the causal relationships among GDP, export, imports and remittances. The study, among others, investigated the validity of export-led and remittances-led growth hypotheses. Specifically, the study investigated the causal relationship between remittances and GDP, remittances and export and remittances and imports. Employing a VECM Granger Causality for data spanning between 1980 and 2012, imports and remittances significantly Granger-caused GDP in the short run. Also, there were reverse causalities running from GDP to export and imports. This implies that export-led growth hypothesis holds in Nigeria. Furthermore, there was a unidirectional causation running from remittances to GDP, implying that remittances matter for economic growth. But since the effect was more from the demand side, it could lead to inflationary pressure. The policy recommendation is that the authorities should intensify efforts on the export base of the economy. The monetary authorities should implement necessary policy to cool the pressure arising from conspicuous spending of remittances.

This study provides additional information about the drivers of external reserves in Nigeria.  The result using Autoregressive Distributed Lag (ARDL) model estimation approach for the period 1980-2015 shows that remittances, among other macroeconomic variables, increased external reserves in the short run but weakens it in the long run. Remittances depletes external reserves through its effect on inflation rate and the nonsterilized intervention of the Central Bank.  Furthermore, regime shift to relatively floating exchange rate causes remittances to increase reserves.  From the foregoing, it is important for the authorities to continue operating relatively flexible exchange rate, and curtail excessive spending of remittances.   Keywords: , , , , . JEL Classification: F31, F24, C22, F31

The study investigates the stock market efficiency of selected OPEC member countries within the context of random walk hypothesis and volatility approaches using monthly data on stock market indices from January, 2005 to April, 2016. Parametric (variance ratio: homoskedastic and heteroskedastic martingale), nonparametric (the Wright ranks and scores) tests and ARCHtype estimation are performed. Results of both parametric and nonparametric tests indicate that only Qatar's stock market is weak-form efficient. The volatility results suggest that monthly stock returns of OPEC countries are volatile, with Qatar being most volatile and shocks to volatility of stock returns are asymmetric. The implications of this are that: first, investors should be conscious of these shocks when making risk-return decision of their portfolios; second, the results provide useful information to regulators to enable them develop safeguard mechanisms to shield the market from possible asymmetric information emanating from the participants.

The link among energy use, human welfare, and carbon emission has been a topical issue in the literature. In Africa, energy consumption has been on the increase owing to the production and consumption of sophisticated consumer goods and home appliances. Increased energy use triggers carbon emission that is detrimental to human welfare. This study investigates this puzzle in emerging African countries by utilizing panel vector autoregressive and system generalized method of moments (SYS-GMM) in the context of a mix of theories. The results indicate a unidirectional causality running from FUEL, COAL to per capita income (PCI). A unidirectional causality running from mortality rate (MOR) to COAL and CO2 was observed. There is a bidirectional relationship between MOR and energy use. The SYS-GMM results show that the effects of energy consumption on well-being are diverse. Increase in coal consumption reduces unemployment rate while electricity consumption reduces infant mortality rate. Fuel consumption aggravates incidence of mortality rate. CO2 reduces unemployment but worsens infant mortality rate. Electricity consumption reduces infant mortality rate. Hence, for the purpose of policy harmonization tailored toward improving well-being in the emerging economies of Africa, it is recommended that more of coal consumption and efficient use of electricity must be encouraged.

The study investigates the determinants of selected manufactured imports in Nigeria with a special focus on the role of domestic production. The autoregressive distributed lag (ARDL) in the context of new trade theory was utilised with data coverage between 1985 and 2016. Results show that imports of various manufactured products are affected differently by some factors. In particular, domestic output of electrical & electronics have a significant and negative effect on own imports. However, there was no significant effect of domestic production of petroleum products on imports of the same goods. Also, the effect of domestic output of food & beverages on imports of same product is positive. Further, the sensitivity of imports to exchange rate changes differ across products, in some it have immediate effect while in some it delays for a year. In the same vein, while GDP is an important driver of imports of some products, it is unimportant for some. Also, it is only food & beverages imports that significantly respond to change in tariffs. The overall conclusion from this study is that drivers of import demand differ across products.