Research and Publication

A. Peer-reviewed publications

1. The Impact of economic sanctions on income inequality of target statesWorld Development (2016), 83, 1-11. (with Mahadevan R.)


In this paper, we draw on established theoretical work to empirically analyze which segments of the population in the target states bear the most cost when economic sanctions are imposed. More specifically, we examine whether the imposition of sanctions affects the income shares of political/economic elites differently from the poorer segment of the population, and adversely skews the income distribution. To account for the fact that sanctioning states employ different instruments of sanctions, we examine whether there exists any differential effect of different instruments of sanctions. Finally, we consider the duration of the economic sanctions to distinguish their impact on income inequality when sanctions span short and long periods.  (Link to working paper

2. Revisiting the effect of regional integration on African trade: Evidence from meta-analysis and gravity model,  Journal of International Trade and Economic Development, (2017), 26(2), 133-153.


Two main shortcomings flaw the estimation of gravity model in previous studies that examined the trade-creating effects of African regional Trade Agreements (RTAs). First, these studies fail to account for the multilateral resistance term (MRT). This omission makes the estimates from standard gravity model bias and inconsistent. Second, there is a significant proportion of zero trade flows, however, these studies also fail to account for them properly. They use either the Tobit model or replace zero flows with arbitrary small values. Apart from these problems, they also exhibit considerable heterogeneity in the RTA effects on trade. In this paper, a meta-analysis of previous empirical studies is conducted to derive a combined effect size and also explain heterogeneity in RTA effects. In addition, I use the gravity model to compare the trade-creating effect of the main African RTAs. Using the gravity model, I compare the estimation methods of previous studies to the Poisson pseudo-maximum-likelihood estimator that tackles the zero flows. From the meta-analysis, I find a general positive effect of African RTAs of about 27-32% after correcting for publication bias. The source of upward bias is not limited to publication selection as the RTA effects tend to be significantly overestimated when zero flows and MRT are not controlled for properly. A comparative assessment of the RTAs shows a striking heterogeneity. (Link to working paper

3. Impact of Economic Diplomacy in Africa: The impact of  Regional Integration versus Bilateral Diplomacy on Bilateral Trade, Handbook of Economic Diplomacy Research, Edward Elgar Publishing, UK, Forthcoming


The paper examines the impact of two main instruments of economic diplomacy - regional integration and bilateral diplomacy on exports among African states. We test whether there is evidence of a trade-off or complementary interaction between regional integration and commercial diplomacy in trade facilitation. We compare the effects of these two instruments of economic diplomacy on bilateral trade by employing a gravity model for 45 African states over the period 1980-2005. The results show that bilateral diplomatic exchange is a relatively more significant determinant of bilateral exports among African states compared to regional integration. We also find a nuanced interaction between these two instruments of economic diplomacy: the trade–stimulating effect of diplomatic exchange is less pronounced among African countries that shared membership of the same regional bloc. Generally, this could mean that there exists a trade-off between regional integration and commercial diplomacy in facilitating exports or a lack of complementarity between these two instruments of economic diplomacy.

4. Measuring multi-membership in economic integration and Its trade impact: A comparative study of ECOWAS and SADC. South African Journal of Economics, (2014), 82(4), 518-530.( with Peter van Bergeijk)


One of the intriguing aspects of African regional trade agreements (RTAs) is the extent of multi-membership, where many African countries are members of more than one RTA. Using a gravity model for 25 countries and the years 1980-2006, we measure the extent of multi-membership and compare its impact in two major African regional blocs, Economic Community of West Africa States (ECOWAS) and Southern Africa Development Community (SADC). We find that the impact of multi-membership critically depends on the characteristics of the multi-membership of regional integration initiatives. We find a positive impact if an additional membership complements the integration process of the original regional integration initiative: overlapping memberships had a much stronger and significant positive effect on bilateral trade within ECOWAS compare with an insignificant impact within the SADC (Link to paper)

B. Working Papers

1.The impact of economic sanctions on international trade: How do threatened sanctions compare with imposed sanctions?


In this paper, we draw on established theoretical works in international political economy to compare the empirical impact of the threat of economic sanctions to the actual imposition of economic sanctions on international trade. Deepening the analysis, we analyze whether there are any differential effects when different instruments are employed. We also examine the international trade effect of sanctions at a more disaggregated products level. Thus, we are able to test whether sanctions have any adverse effect on essential commodities such as food and medical supplies in contravention of the Geneva Convention which stipulates the passage of such essential goods even in times of sanction. To achieve this, we use the gravity model as our empirical tool and recent detailed disaggregated data on sanctions spanning a long time series from 1960 to 2009. Our results show that the impact of threatened sanctions differs qualitatively and quantitatively from imposed sanctions. Whereas imposed sanctions lead to a decrease in the trade flow between the sender and  the target, a threat of sanctions leads to an increase in the trade flow. The positive impact of the threat may be due to economic agents in both the sender and its target resorting  to stockpiling prior to the actual imposition of sanctions to minimize any adverse consequences of the sanctions. In addition, we find varying effects for the different sanction instruments. Also, the detrimental effect of sanctions extends to essential products.

2. Preferential market access, foreign aid and economic development (with Dr. Kaleb Girma Abreha) Under review


Several studies highlight that exporters in LDCs face substantial trade costs exporting to developed countries. To this end, preferential market access granted by developed countries is expected to play a pivotal role especially in reducing non-tariff barriers. However, granting preferential market access may be necessary but not a sufficient condition to promote economic development in the case of LDCs mainly because there are endemic structural constraints. These constraints undermine the capacity of LDCs’ producers to utilize these market access opportunities effectively. Focusing on the EU-ACP non-reciprocal preferential market access, we show that the EU preferential scheme is effective in promoting exports, however, this market access only improves economic development if it is complemented with a sufficient level of foreign aid targeted at trading activities. (Link to paper


3. Aid, inequality and regime change revisited (With Prof. Dr. Christian Bjørnskov). Under review 


The effectiveness of foreign aid on economic growth has been extensively researched but with quite controversial and negative results. In this paper, we instead revisit the question if foreign aid affects the distribution of income. Our question is predicated on the premise that even if aid does not affect the long-run growth rate, it might still reduce poverty by affecting the within-country income distribution. Compared to the existing literature, our paper introduces three new features: 1) the use of new and more precise, comparable data on income inequality enabling the separation of pre and post-policy inequality; 2) measures of aid decomposed into four separable types; and 3) the distinction between stable and unstable regime types. In panel estimates from 110 developing countries for the period 1975-2010, we find that while most aid is ineffective in affecting the income distribution, one type does so adversely under non-democratic political institutions. (Link to paper)

C. Work-in-Progress

1. The Economic Consequences of Xenophobic Attacks: Evidence from South Africa

2. The Impact of E-reader on Student Performance: Evidence for Randomized Controlled Trial from Ghana.

3. WTO Disputes and International Trade (With Prof. Bernard Hoekman).

4. Impact of Non-Tariff Measures in West Africa. Project commissioned and funded by African Development Bank and International Trade Centre.