Quality of Road Transport Infrastructure and Intra-African Agricultural Exports: A Long Run Two-Step System Generalized Method of Moments Analyses
Copyright © 2026 Lathiff Sesay, Julius Mangisoni, Innocent Pangapanga‑Phiri, Assa M. Maganga. Published by Nan Yang Academy of Sciences Pte. Ltd.
This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.
Abstract
Sustainable growth requires developing economies to simultaneously attain economic and environmental sustainability. This study examines the effect of the quality of road transport infrastructure of the exporting and importing countries on intra-African agricultural exports from 2006 to 2018. To achieve this objective, the study employed the two-step system generalized method of moments, short-run and long-run estimators. The pooled mean group estimator was also used as a robustness check. The results revealed that the quality of road transport infrastructure of the exporting countries increases intra-African agricultural exports by an average of 1.24 to 1.25 percentage points in the short-run and 1.80 to 2.01 percentage points in the long-run. Furthermore, the role of Africa’s regional trading blocs in determining intra-African agricultural exports was also analyzed. The results showed that the East African Community (EAC), the Economic Community of West African States (ECOWAS), and the Southern African Development Community(SADC) increase intra-African agricultural exports. However, the EAC is more integrated than the SADC, followed by the ECOWAS, in both the short and long-run. Thus, exporters’ quality of road transport infrastructure and regional trading blocs promote intra-African agricultural exports. The study recommends strengthening the political and institutional will of national authorities to support green road construction and rehabilitation financing and investments, de-risk, and co-promote green road infrastructure projects to attract investments in road transport infrastructure.
Keywords: Road Transport Infrastructure, Intra-African Agricultural Exports, Two-Step System Generalized Method of Moments, Pooled Mean Group, Regional Trading Bloc
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