S7 Ep49: Follow the paper trail

In Uganda, every sale between two VAT-registered firms reaches the tax authority twice. The seller reports it, and so does the buyer. But the two numbers rarely match. In Turkiye, a supplier that installs its first industrial robot doesn’t make an announcement, but the administrative records can track when the firms automate, and what happens next.

Justine Knebelmann and Nuriye Melisa Bilgin tell Tim Phillips how they used those records to find out more about the choices firms make, and the effects on the firms around them. Justine and her co-authors worked with the Uganda Revenue Authority to send letters to firms whose reports did not match their trading partner’s, to find out under what conditions the firms amended their tax returns. Nuriye mapped robot adoption across Turkiye's firm-to-firm network, to find out the competitive effects. They also discuss how researchers can access administrative data, and how simply compiling it can change policy.

The research behind this episode:

Almunia, Miguel, David J. Henning, Justine Knebelmann, Dorothy Nakyambadde, and Lin Tian. 2023. "Firm Networks and Tax Compliance: Experimental Evidence from Uganda." CEPR Discussion Paper 18151, revised October 2025. 

Bilgin, Nuriye Melisa, Ester Faia, and Gianmarco Ottaviano. 2024. "Technology Spillovers, Diffusion and Rivalry in Firm Networks." CEPR Discussion Paper 19804. 

To cite this episode:

Phillips, Tim, Justine Knebelmann, and Nuriye Melisa Bilgin. 2026. "Follow the paper trail." PEDL (podcast). Centre for Economic Policy Research.

About the guestsJustine Knebelmann is an Assistant Professor in the Department of Economics at Sciences Po, Paris, and an Associate at the Institute for Fiscal Studies. Her research spans state capacity in developing countries, tax administration, digitalisation and land. She has worked with tax administrations in Sub-Saharan Africa since 2015.

Nuriye Melisa Bilgin is a Lecturer in Economics at Koç University and a Senior Fellow at the Microsoft AI Economy Institute. Her research spans technology adoption, from industrial robots to generative AI, and how new technologies and shocks travel through production networks and global value chains, using large-scale firm-to-firm transaction data from Turkiye. She held postdoctoral positions at Bocconi University and the University of Turin.

About PEDLPrivate Enterprise Development in Low Income Countries (PEDL) is a joint research initiative of the Centre for Economic Policy Research (CEPR) and the Foreign, Commonwealth & Development Office (FCDO), and part of CEPR's Growth Research Platform. Established in 2011, it funds research on private-sector development in low-income countries. Find out more at grp.cepr.org/pedl.

Research cited in this episodeValue-added tax (VAT). Firms charge VAT on their sales and reclaim the VAT they paid on inputs bought from other registered firms. Because every business-to-business sale appears on two returns, one from each side, the tax authority can in principle check one report against the other. Economists call this the VAT's self-enforcing property. In Uganda the VAT raises about 30% of total tax revenue, according to IMF figures cited by Almunia and co-authors; the IMF puts Uganda's VAT compliance gap at around 60% of potential VAT revenue.

Seller shortfall. The Uganda team's term for a transaction in which the seller reports a smaller amount than the buyer. It lowers the tax bill and often signals evasion. In the 10 months before t