【正文】 on one or all the variables used. Such innovations are always present in the field of technology not least energy. For example, effective conservation measures, efficient energy end use appliances and changes in the laws affecting transport and urban planning will affect energy intensity relative to economic activities. Accordingly, Pierce and Hughes (1977) suggested that one way of accounting for 39。 the United Nation39。 Pearson, 1987。modern39。 in total output. This being the case, energy price changes will have a relatively small impact on the economy, especially taking into account substitution possibilities provided by other factors of production. Implicitly, perfect factor substitution has been assumed between energy, labour and capital. The size assumed for the substitution coefficient is an important consideration to this debate. It appears that the coefficient assumed by Okun (1974, 1975) is much higher than that adopted by RascheTatom (1977). Thus, an increase in energy prices will result in the substitution of labour for capital. Others have supported this view. Perry (1975, 1977) has suggested that 39。 ....... 3 Energy, economic growth and causality in developing countries: A case study of Tanzania and Nigeria The debate about the precise role of energy in economic development remains contentious. Existing empirical studies have produced varying results: some have argued the plementarity between energy and other factors of production, and others have indicated that energy can be substituted for other factors of production. Commonly, these studies have focused primarily on the developed countries, one explanation being that supply constraints and price rigidities render any study on factor substitutions in developing countries meaningless. However, the functional relationship between en ergy consumption and ine in developing countries is constantly investigated with the use of regression techniques. While such techniques are useful in empirical analysis, no mechanism exists for indicating causal directions between variables. This limits the scope for policy analysis and prescription. The need to identify causal direction between energy consumption and ine growth in devel oping countries is overwhelming. Apart from providing further insights into the role of energy in economic development, it provides policy analysts with a clearer understanding of the likely impact of energy supply constraints on economic growth. This article examines the causal directions be tween energy consumption and economic growth (proxied by GDP and GNP) for Nigeria and Tan zania. The results show a simultaneous causal relationship between energy and economic growth for both countries, the implication being that, unless energy supply constraints are eased, economic growth and development will remain elusive to these countries. Given similar economic characteristics and profiling the same energy scenario for other developing countries, our finding supports the view that energy plays a key role in economic development. Copyright 169。 發(fā)達(dá)國家和發(fā)展中國家是不利于基本經(jīng)濟(jì)目標(biāo)和目標(biāo)的充分就業(yè)，經(jīng)濟(jì)增長，低廉的價格和更高的生活水平，這是世界各國政府的優(yōu)先級之間的差距越來越大。與此同時，出口收匯幾乎足以影響能源進(jìn)口。雖然從這個來源完全滿足農(nóng)村能源需求，只有 10％的城鎮(zhèn)人口使用的商業(yè)能源（安德森和菲舍維克， 1984年）。他們觀察到，這依賴于歐佩克 197374和 197980的價格上漲被認(rèn)為辯論。它似乎假定者奧肯（ 1974年， 1975年）的系數(shù)是比通過的 Rasche Tatom（ 1977）的高得多。 首先出現(xiàn)的是宏觀 經(jīng)濟(jì)學(xué)家的解釋是在 197374和 1978年至 1979年成品油價格上調(diào)對全球經(jīng)濟(jì)的“供給沖擊”達(dá)成共識。其含義是，除非緩解能源供應(yīng)的限制，否則對這些國家的經(jīng)濟(jì)增長和發(fā)展將仍然是難以捉摸的。 現(xiàn)有的實(shí)證研究產(chǎn)生了不同的結(jié)果：一些人認(rèn)為能源和其他生產(chǎn)要素之間是互補(bǔ)性關(guān)系，而其他人表示，能源可以替代其他生產(chǎn)要素。 除了從能源在經(jīng)濟(jì)發(fā)展中的作用提供了進(jìn)一步的深入了解，提供政策分析，更清楚地了解能源供給約束對經(jīng)濟(jì)增長可能帶來的影響。然而，能源的影響基準(zhǔn)的幅度對經(jīng)濟(jì)的作用引起了宏觀經(jīng)濟(jì)學(xué)家的激烈辯論。在這種情況下，能源價格變動對經(jīng)濟(jì)的影響相對較小，尤其是考慮到帳戶提供其他替代的可能性生產(chǎn)因素。我明確，有一個先決條件，現(xiàn)有的理論經(jīng)濟(jì)生產(chǎn)力的發(fā)展趨勢，應(yīng)適當(dāng)?shù)靥幚砟茉次C(jī)。非洲的能源結(jié)構(gòu)密切監(jiān)察蒙上巨大的懷疑其能否實(shí)現(xiàn)可持續(xù)的經(jīng)濟(jì)增長和發(fā)展，賦予其能源問題。 在商業(yè)能源部門，短缺比比皆是。世界銀行估計，這將每年花費(fèi) US $ 28億美元的投資，必須持續(xù)超過 10年的時間內(nèi)，以便在非洲的能源供應(yīng)能力（世界銀行， 1988年）每年 5％的溫和擴(kuò)張。努力在 subSaharan 非洲國家的經(jīng)濟(jì)現(xiàn)代化， 必須采取長期的能源問題。supply shocks39。indirect39。 Ang, 1987。s total debt obligations, is more than 80%. Without a mensurate ex pansion in exports and export revenues, such huge energy expenditure remains unsustainable. This bees a vicious circle and is a dilemma because of the energy implication of boosting exports. Given these constraints, it es as no surprise to find that up to 68% and in some cases up to 90% of developing countries urban population depend on woodfuel and other agricultural biomass residues for energy (Millington et al, 1994。 but the crucial role of fertilizers, processing, and transport in production activities highlight the importance of energy. Indeed, energy related transport and other difficulties have resulted in huge postharvest losses in these countries (Makhijiani and Poole, 1975). Thus, this finding serves to strengthen the relationship between energy and national ine in Tanzania. The implication is that energy shortages can seriously hinder economic growth and development. As indicated, the Fstatistic is not usually used as a measure of significance in the Granger test but we have used it to test whether the inclusion of 14 past values in the regression enhances the significance of the whole regression. The Ftests for all the regressions were significant at the 5% level of significance. The figures in parenthesis are DWstatistics which were used to test for the presence of autocorrelation and the values indicate the absence of first order autocorrelation. The need for an instantaneous causality test follows from the observations made by Granger that if a dislocated sequence occurs in the data (ie if Y causes E to occur with one period lag, instead a two period lag was observed) it could result in 39。s export proceeds went to oil imports in 1987, to the detriment of other equally vital sectors of the economy (Davidson, 1992). The instantaneous causal direction be tween