{"title":"Identifying Drivers of Deviations From Rational Expectations: Using a New Irrational Index for Inflation Forecasts","authors":"Belen Chocobar, Peter Claeys","doi":"10.1002/for.70136","DOIUrl":"https://doi.org/10.1002/for.70136","url":null,"abstract":"<p>Most studies on inflation forecasts have studied behavioral biases, informational frictions, or external shocks in isolation, without considering how these factors jointly drive deviations from rational expectations. We therefore adopt an integrated framework that simultaneously estimates the behavioral, informational, and external determinants of deviations from rationality. To measure the deviations, we develop a novel irrationality index—following Rossi and Sekhposyan's (2016) Fluctuation Rationality Test—to measure experts' time-varying deviations from rationality in US year-ahead inflation forecasts between 2010 and 2022. We then estimate the impact of different behavioral, informational, and external drivers on deviations from rationality using panel models. Our results indicate that external information shocks, interest rate expectations, as well as geopolitical risk all significantly drive the deviations from rationality. These findings highlight the value of a unified approach to expectation formation, moving beyond the isolated analyses that are common to the literature.</p>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2160-2172"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/for.70136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhanced Bagging-Based Approach for Forecasting Nonstationary Time Series: Bridging Nonstationarity With a Scaled Logit Transformation","authors":"Young Eun Jeon, Yongku Kim, Jung-In Seo","doi":"10.1002/for.70138","DOIUrl":"https://doi.org/10.1002/for.70138","url":null,"abstract":"<div>\u0000 \u0000 <p>Traditional block bootstrapping methods, such as the moving block bootstrap, can effectively preserve serial dependence within blocks when the underlying time series is stationary; however, when applied to nonstationary data, these methods often fail to capture evolving dependence structures, which can substantially undermine the performance of bagging predictors. This limitation highlights the need for effective strategies that transform nonstationary time series into stationary counterparts before bootstrapping, thereby enabling the reliable application of block bootstrapping in nonstationary settings. Motivated by this issue, this study develops an enhanced bagging-based approach incorporating a scaled logit transformation and a decomposition technique. In particular, the scaled logit transformation operates without parameter estimation and effectively stabilizes variance for data containing negative values or bounded ranges, such as proportions and rates, unlike a Box–Cox transformation, which relies on parameter estimation and requires positive data. The effectiveness of our method is examined through two illustrative studies: a simulation study and a real data analysis. In the simulation study, its performance is evaluated using various nonstationary time series generated under controlled conditions. For the real data analysis, three nonstationary time series datasets with different frequencies are utilized to substantiate its practical applicability.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2300-2308"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nikolaos Giannellis, Stephen G. Hall, Georgios P. Kouretas, George S. Tavlas, Yongli Wang
{"title":"Macroeconomic and Financial Forecasting in the Aftermath of the Covid Shock: Inflation Forecasting With Large Language Models","authors":"Nikolaos Giannellis, Stephen G. Hall, Georgios P. Kouretas, George S. Tavlas, Yongli Wang","doi":"10.1002/for.70139","DOIUrl":"https://doi.org/10.1002/for.70139","url":null,"abstract":"<div>\u0000 \u0000 <p>We compare the inflation forecasting performance of large language models (LLMs) to traditional models and the Kalman filter approach developed by Hall et al. (2026). Using monthly data for inflation in both the United States and the euro area, we forecast over the period 2020:M1 to 2025:M9; our findings show that all the LLMs significantly improved forecasting performance against the traditional models.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2115-2121"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A New Proposal for Forecasting Inflation in the Eurozone: A Global Model","authors":"Georgios Angelopoulos, Zacharias Bragoudakis, Dimitrios Dimitriou, Alexandros Tsioutsios","doi":"10.1002/for.70135","DOIUrl":"https://doi.org/10.1002/for.70135","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper evaluates the forecasting performance of the relatively new machine learning Global Unrefined (GlobalUN, hereafter) model with respect to inflation in the Eurozone. In this global pooled neural network framework, we use a quarterly panel dataset covering 20 euro-area countries (2001Q1–2025Q1) together with the EA-20 aggregate, which includes key variables such as HICP, energy prices, food, and others. Thus, the network remains simple yet flexible enough to absorb heterogeneity across countries. Our work's contribution is crucial since monetary policy in the Eurozone hinges on accurate inflation forecasts (i.e., as ECB decisions target expected rather than current inflation). Our findings are crystal clear. The GlobalUN model outperforms all other benchmark models and the advanced machine learning XGBoost model in almost all Eurozone countries and horizons (i.e., the naïve model seems to outperforms in a few cases). These results are useful for policymakers, central banks, and fiscal institutions, as they should take the GlobalUN model into account as part of their arsenal.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2393-2425"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Forecasting Disaggregated Producer Prices: A Fusion of Machine Learning and Econometric Techniques","authors":"Soňa Benecká","doi":"10.1002/for.70149","DOIUrl":"https://doi.org/10.1002/for.70149","url":null,"abstract":"<div>\u0000 \u0000 <p>I propose a novel framework for forecasting euro-area disaggregated producer prices that blends machine-learning methods with traditional econometric models. Working at the sector level pays: Pricing behavior is heterogeneous, and no single model dominates across sectors or horizons. This highlights the necessity for a tailored approach that leverages the strengths of various forecasting methods to effectively capture the unique characteristics of each sector. My forecasting exercise has highlighted diverse pricing strategies linked to commodity prices, autoregressive behavior, or a mixture of both, with pipeline pressures being especially pertinent to final goods. Tree-based methods—random forest and XGBoost—perform strongly, especially where pipeline pressures and input-cost signals are informative. Newly proposed hybrid RF-ARMAX and XGB-ARMAX models are particularly effective for short-term PPI inflation in commodity- and energy-sensitive sectors.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2458-2501"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148387026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Noman Arshed, Shajara Ul-Durar, Younes Ben Zaied, Marco De Sisto
{"title":"Forecasting European Union Electronic Trading Systems Phase 4 Spot Prices Using Data-Driven Hybrid Deep Learning Models: Integrating Energy and Market Activity as Controls","authors":"Noman Arshed, Shajara Ul-Durar, Younes Ben Zaied, Marco De Sisto","doi":"10.1002/for.70152","DOIUrl":"https://doi.org/10.1002/for.70152","url":null,"abstract":"<div>\u0000 \u0000 <p>Amid the focus on climate change mitigation, this study explores carbon market forecasting. This study uses a hybrid forecasting framework that integrates empirical model decomposition, bidirectional long short-term memory (BiLSTM) network, and attention mechanism to enhance the predictive performance of carbon spot prices within the European Union (EU) Emissions Trading System (ETS). The model decomposes the nonstationary carbon prices to multiple intrinsic mode functions (IMF) representing each distinct frequency component. The forecasting at IMF level enables learning of temporal dependence and volatility. The final model reconstructs the signals to present overall prediction. The multiple iterations that include a selection of macroeconomic variable led to the final root mean square errors (RMSE) value of 4.59, which shows that the BiLSTM outperforms a conventional long short-term memory (LSTM) setup. This study also improves the model by including exogenous macroeconomic variables and policy shocks to enhance predictive accuracy. Shapley additive explanations (SHAP) analysis also identified the important features and variables. The visualized confidence interval confirms the reliability of the forecasts. The findings of the study highlight the effectiveness of integrating signal decomposition with deep learning and inclusion of exogenous factors. This study offers practical insights for regulators and researchers who are engaged in the emissions market and climate finance.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2502-2524"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148387027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Inflation Forecasting Post-COVID-19: Evidence From Germany","authors":"Tiphaine Wibault","doi":"10.1002/for.70142","DOIUrl":"https://doi.org/10.1002/for.70142","url":null,"abstract":"<div>\u0000 \u0000 <p>I compare the forecasting performance of a wide range of univariate and multivariate forecasting models for both headline and core inflation in Germany. The analysis is conducted using a full sample containing quarterly data from 1995 to 2024, which includes the COVID-19 pandemic and subsequent inflation surge, and a shortened sample spanning the years 1995–2019, a period of low and stable inflation. I firstly find evidence to support a recurrent finding in the literature that univariate models are hard to beat but show that this holds particularly for single-indicator models, at times of stable inflation. Furthermore, upon testing 34 indicators for German inflation in both single-indicator and combination (i.e., factor, pooling, and BVAR) models, I find that the performance of multivariate models is improved by (i) including the years 2020–2024 in which inflation was high and volatile and (ii) by <i>combining</i> information contained within the indicators. Specifically, I find that the multivariate models improve upon the univariate benchmark by up to 20% in the full sample, providing evidence for the performance of forecasting models to vary with the economic environment. The analysis also sheds light on which indicators are particularly useful for forecasting inflation in Germany. Additionally, it appears that multivariate models provide a greater forecasting gain over the univariate benchmark for headline, rather than core, inflation. Finally, a short case study of the inflation pickup following the COVID-19 pandemic reveals that the multivariate models, particularly the factor, BVAR, and price expectations single-indicator models, most accurately forecasted inflation at this time.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2238-2265"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evaluating Forecasts at Multiple Horizons: An Extension of the Diebold–Mariano Approach","authors":"Andrew Grant, Matus Mrazik, Steve Satchell","doi":"10.1002/for.70150","DOIUrl":"https://doi.org/10.1002/for.70150","url":null,"abstract":"<p>Forecast accuracy tests are fundamental tools for comparing competing predictive models. The widely used Diebold–Mariano (DM) test assesses whether differences in forecast errors are statistically significant. However, its standard form is limited to pairwise comparisons at a single forecast horizon. A number of solutions to this exist in the literature. Relative to these, this paper, based on a Mahalanobis approach, rather than approaches based on asymptotic normality. Our method incorporates cross-covariances between errors and generalizes the DM framework to account for overlapping forecast windows and autocorrelation. The test provides a transparent alternative for forecasters and practitioners needing unified inference across temporal spans. We use simulations to assess conditions under which our test performs well, showing promising results in situations where big data are likely to be applicable.</p>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2379-2392"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/for.70150","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Intraday Functional PCA Forecasting of Cryptocurrency Returns","authors":"Joann Jasiak, Cheng Zhong","doi":"10.1002/for.70127","DOIUrl":"https://doi.org/10.1002/for.70127","url":null,"abstract":"<p>We study the functional PCA (FPCA) forecasting method in application to functions of intraday returns on Bitcoin. We show that improved interval forecasts of future return functions are obtained when the conditional heteroscedasticity of return functions is taken into account. The Karhunen–Loeve (KL) dynamic factor model is introduced to bridge the functional and discrete-time approaches. It offers a convenient framework for the analysis of conditionally heteroscedastic functional time series. For intraday forecasting of incomplete functions, we introduce a new algorithm based on the FPCA applied by rolling, which can be used for any data observed continuously 24/7. The proposed forecasting methods are applied to return functions computed from data sampled hourly and at 15-min intervals. The proposed pointwise forecast intervals for complete functions show improved accuracy compared to the literature. Our intraday pointwise hourly forecasts of Bitcoin returns compare favorably with competitors in the recent literature, in terms of directional (sign) and accuracy.</p>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2186-2212"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/for.70127","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"AI-Driven Inflation Forecasting in the Aftermath of COVID-19","authors":"Krystian Jaworski","doi":"10.1002/for.70148","DOIUrl":"https://doi.org/10.1002/for.70148","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper develops a hybrid approach to inflation forecasting that combines large language models (LLMs) with traditional econometric methods. We construct a novel indicator of inflation expectations by applying GPT-4o to classify Twitter discussions among economists and financial commentators in the United States, the Eurozone, and Poland. Embedded in an ARIMAX framework, this indicator delivers systematic predictive content and consistently anticipates inflation dynamics up to 1 year ahead. Out-of-sample tests show that AI-augmented forecasts achieve statistically significant accuracy gains over both professional consensus forecasts and benchmark ARIMA models, particularly at medium and long horizons. Robustness checks—including alternative smoothing and lag structures, model variants, prompt formulations, and metadata weighting—confirm the stability of results across regions and specifications. By integrating high-frequency, sentiment-based signals with econometric forecasting, the study demonstrates how generative AI can complement conventional tools, offering central banks, policymakers, and financial market participants an early-warning mechanism during periods of uncertainty and structural change. While the approach is constrained by its reliance on Twitter data and the interpretability limits of LLMs, it highlights the transformative potential of hybrid AI-econometric frameworks for real-time macroeconomic analysis.</p>\u0000 </div>","PeriodicalId":47835,"journal":{"name":"Journal of Forecasting","volume":"45 5","pages":"2525-2548"},"PeriodicalIF":2.6,"publicationDate":"2026-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148386451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}