Transparency and Forecasting: The Impact of Conditioning Assumptions on Forecast Accuracy
Katja Heinisch, Christoph Schult, Carola Stapper
Applied Economics Letters,
forthcoming
Abstract
This study investigates the impact of inaccurate assumptions on economic forecast precision. We construct a new dataset comprising an unbalanced panel of annual German GDP forecasts from various institutions, taking into account their underlying assumptions. We explicitly control for different forecast horizons to reflect the information available at the time of release. Our analysis reveals that approximately 75% of the variation in squared forecast errors can be attributed to the variation in squared errors of the initial assumptions. This finding emphasizes the importance of accurate assumptions in economic forecasting and suggests that forecasters should transparently disclose their assumptions to enhance the usefulness of their forecasts in shaping effective policy recommendations.
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01.04.2026 • 10/2026
Economic growth in East Germany slightly higher than in the West – Implications of the Joint Economic Forecast Spring 2026 and of new data for the East German economy
In 2025, the East German economy expanded by 0.4%, somewhat more than Germany as a whole (0.2%). For 2026, the Halle Institute for Economic Research (IWH) expects growth of 0.7% for East Germany (Germany: 0.6%). The unemployment rate is likely to amount to 7.9% in the current year, after 7.8% in 2025.
Oliver Holtemöller
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12.03.2026 • 8/2026
Oil price shock threatens recovery in Germany
Globally rising energy prices in the wake of the new Gulf War are clouding the outlook for the German economy. Nevertheless, increased public expenditure is expected to support economic activity both this year and next. According to the spring forecast of the Halle Institute for Economic Research (IWH), output is projected to grow by 0.7% in 2026 and by 1.0% in 2027. We expect similar rates of expansion for East Germany. In December, the IWH economists had predicted growth of 1.0% for both 2026 and 2027.
Oliver Holtemöller
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Privacy
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IWH Bankruptcy Research
IWH Bankruptcy Research The Bankruptcy Research Unit of the Halle Institute for Economic Research (IWH) presents the Institute’s research on the topics of corporate bankruptcy,…
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Centre for Evidence-based Policy Advice
Centre for Evidence-based Policy Advice (IWH-CEP) The Centre for Evidence-based Policy Advice (IWH-CEP) of the IWH was founded in 2014. It is a platform that bundles and…
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Halle Institute for Economic Research
Between Energy Crisis and AI Boom The summer forecast of the Halle Institute for Economic Research (IWH) assumes that the Gulf conflict eases and energy prices do not rise…
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IWH Subsidy Database
IWH Subsidy Databse The microdatabase currently comprises nine data sets on direct business subsidy programmes in Germany. The programme statistics kept by the project sponsors…
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Voting under Debtor Distress
Jakub Grossmann, Štěpán Jurajda
Electoral Studies,
Vol. 95 (June),
2025
Abstract
There is growing evidence on the role of economic conditions in the recent successes of populist and extremist parties. However, little is known about the role of over-indebtedness, even though debtor distress has grown in Europe following the financial crisis. We study the unique case of the Czech Republic, where by 2017, nearly one in ten citizens had been served at least one debtor distress warrant even though the country consistently features low unemployment. Our municipality-level difference-in-differences analysis asks about the voting consequences of a rise in debtor distress following a 2001 deregulation of consumer-debt collection. We find that debtor distress has a positive effect on support for (new) extreme right and populist parties, but a negative effect on a (traditional) extreme-left party. The effects of debtor distress we uncover are robust to whether and how we control for economic hardship; the effects of debtor distress and economic hardship are of similar magnitude, but operate in opposing directions across the political spectrum.
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14.05.2025 • 16/2025
Private ownership boosts hospital performance
New research by the Halle Institute for Economic Research (IWH) and ESMT Berlin shows that private equity (PE) acquisitions lead to substantial operational efficiency gains in hospitals, challenging common public concerns. The study reveals that hospitals acquired by PE firms significantly reduce costs and administrative staff without increasing closure rates or harming patient care.
Merih Sevilir
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