Publications

The cemmap working paper series publishes papers expanding the frontiers of knowledge in microdata methods and practice. Martin Weidner is the editor of the working paper series.

Carbon regulation and competition in the European airline industry

The European Union Emissions Trading System is set to substantially increase the effective carbon price faced… Continue reading.

Ertian Chen, Lichao Chen, Lars Nesheim
March 2026

CWP04/26

Optimal formula instruments

When estimating the effects of treatments defined by complex formulas, researchers often use simple functions of… Continue reading.

Kirill Borusyak, Peter Hull
March 2026

CWP03/26

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Optimal formula instruments
Kirill Borusyak, Peter Hull
March 2025 | CWP09/25
Nonparametric identification of demand without exogenous product characteristics

We study identification of differentiated product demand from market level data when product characteristics can be… Continue reading.

Kirill Borusyak, Jiafeng Chen, Peter Hull, Lihua Lei
February 2026

CWP02/26

Weak instrument bias in impulse response estimators

We approximate the finite-sample distribution of impulse response function (IRF) estimators that are just-identified with a… Continue reading.

Daniel Lewis, Karel Mertens
January 2026

CWP01/26