His early work on finance and growth challenged the view that growth in the financial system is, by itself, sufficient to deliver more economic growth and emphasised the importance of good institutions. Moreover, he has shown that, where present, the contribution of the banking sector to growth is more significant than that of equity finance through the stock market. More recent work has challenged widely held views about government owned banks by showing that, far from acting as an obstacle to growth, such banks can actually enhance both financial and economic development. His work on public capital contradicts the 'crowding out' argument often used by mainstream economists to justify cuts in public spending and reduce the size of government. Specifically, he shows that public investment can actually promote the productivity of the private sector and stimulate trade, employment and long run growth. In this sense, his work has a distinctly Keynesian flavour, influenced by new Keynesians such as Joseph Stiglitz. Although his work can be classified as macroeconomics, he also utilises both micro-data and micro-econometrics. His academic work has been influential, as evidenced by over 8000 citations in Google Scholar. According to the RePEc rankings, he is ranked among the top 1% of the world's most widely read economists as well as the top 5% of economic authors worldwide based on criteria like average rank score, number of works number of distinct works, number of citations etc. Selected academic articles "The Changing Face of Financial Development", with Peter L. Rousseau, Economics Letters, Elsevier, vol. 141(C), pages 87–90, 2015 "Why Do African Banks Lend so Little?", with Svetlana Andrianova and Badi H. Baltagi and David Fielding, Oxford Bulletin of Economics and Statistics, Department of Economics, University of Oxford, vol. 77(3), pages 339–359, 06, 2015 "Financial Restraints And Private Investment: Evidence From A Nonstationary Panel", with Mauro Costantini and Gregory A. James and Kevin C. Lee, Economic Inquiry, Western Economic Association International, vol. 51(1), pages 248–259, 01, 2013 "Government ownership of banks, institutions and economic growth", with S Andrianova, Economica, London School of Economics and Political Science, vol. 79(315), pages 449–469, 07, 2012 "Sources and legitimacy of financial liberalization", with Burgoon, Brian and Underhill, Geoffrey R.D., European Journal of Political Economy, Elsevier, vol. 28(2), pages 147–161, 2012 "Political Economy Origins of Financial Development in Europe and Asia", with S.Andrianova and C.Xu, World Development , 2010 "Financial Development and Openness: Evidence from Panel