{"title":"Properties of the reconciled distributions for Gaussian and count forecasts","authors":"","doi":"10.1016/j.ijforecast.2023.12.004","DOIUrl":"10.1016/j.ijforecast.2023.12.004","url":null,"abstract":"<div><p>Reconciliation enforces coherence between hierarchical forecasts, in order to satisfy a set of linear constraints. While most works focus on the reconciliation of point forecasts, we consider probabilistic reconciliation and we analyze the properties of distributions reconciled via conditioning. We provide a formal analysis of the variance of the reconciled distribution, treating the case of Gaussian and count forecasts separately. We also study the reconciled upper mean in the case of one-level hierarchies, again treating Gaussian and count forecasts separately. We then show experiments on the reconciliation of intermittent time series related to the count of extreme market events. The experiments confirm our theoretical results and show that reconciliation largely improves the performance of probabilistic forecasting.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1438-1448"},"PeriodicalIF":6.9,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S016920702300136X/pdfft?md5=9e8e80067e02ac1e611fc1ae1e5aec76&pid=1-s2.0-S016920702300136X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Acknowledgement to reviewers","authors":"","doi":"10.1016/j.ijforecast.2023.12.001","DOIUrl":"10.1016/j.ijforecast.2023.12.001","url":null,"abstract":"","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 2","pages":"Pages 855-857"},"PeriodicalIF":7.9,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139398219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thinking outside the container: A sparse partial least squares approach to forecasting trade flows","authors":"","doi":"10.1016/j.ijforecast.2023.11.007","DOIUrl":"10.1016/j.ijforecast.2023.11.007","url":null,"abstract":"<div><p>Global container ship movements may reliably predict trade flows. First, this paper provides the methodology to construct maritime shipping time series from a dataset comprising millions of container vessel positions annually. Second, to forecast monthly goods trade using these time series, this study outlines the use of the least absolute shrinkage and selection operator (LASSO) in combination with a partial least squares process (PLS). An expanding window, out-of-sample exercise demonstrates that constructed forecasts outperform benchmark models for the vast majority of 76 countries and regions. The performance holds true for unilateral and bilateral trade flows, for trade of developed and developing countries, for real and nominal trade, as well as for time periods of economic crisis such as the COVID-19 pandemic. The resulting forecasts of trade flows precede official statistics by several months and may facilitate quantification of supply chain disruptions and trade wars.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1336-1358"},"PeriodicalIF":6.9,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S016920702300122X/pdfft?md5=fa38013c58ded3f31d0c99997def111f&pid=1-s2.0-S016920702300122X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139394294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Forecasting day-ahead expected shortfall on the EUR/USD exchange rate: The (I)relevance of implied volatility","authors":"","doi":"10.1016/j.ijforecast.2023.11.003","DOIUrl":"10.1016/j.ijforecast.2023.11.003","url":null,"abstract":"<div><p><span><span>The existing literature provides mixed results on the usefulness of implied volatility for managing risky assets, while evidence for expected shortfall predictions is almost nonexistent. Given its forward-looking nature, implied volatility might be more valuable than backward-looking measures of realized price fluctuations. Conversely, the volatility risk premium embedded in implied volatility leads to overestimating the observed price variation. This paper explores the benefits of augmenting econometric models used in forecasting the expected shortfall, a risk measured endorsed in the Basel III Accord, with information on implied volatility obtained from EUR/USD </span>option contracts<span>. The day-ahead forecasts are obtained from several classes of econometric models: historical simulation, EGARCH, </span></span>quantile regression-based HAR, joint VaR and ES model, and combination forecasts. We verify whether the resulting expected shortfall forecasts are well-specified and test the models’ accuracy. Our results provide evidence that the information provided by forward-looking implied volatility is more valuable than that in backward-looking realized measures. These results hold across multiple model specifications, are stable over time, hold under alternative loss functions, and are more pronounced during periods of higher market uncertainty when risk modeling matters most.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1275-1301"},"PeriodicalIF":6.9,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139374581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A probabilistic forecast methodology for volatile electricity prices in the Australian National Electricity Market","authors":"","doi":"10.1016/j.ijforecast.2023.12.003","DOIUrl":"10.1016/j.ijforecast.2023.12.003","url":null,"abstract":"<div><p>The South Australia region of the Australian National Electricity Market (NEM) displays some of the highest levels of price volatility observed in modern electricity markets. This paper outlines an approach to probabilistic forecasting under these extreme conditions, including spike filtration and several post-processing steps. We propose using quantile regression as an ensemble tool for probabilistic forecasting, with our combined forecasts achieving superior results compared to all constituent models. Within our ensemble framework, we demonstrate that averaging models with varying training-length periods leads to a more adaptive model and increased prediction accuracy. The applicability of the final model is evaluated by comparing our median forecasts with the point forecasts available from the Australian NEM operator, with our model outperforming these NEM forecasts by a significant margin.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1421-1437"},"PeriodicalIF":6.9,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169207023001358/pdfft?md5=ade3ae549bbe5d6169dda529d773ee26&pid=1-s2.0-S0169207023001358-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139374481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
George Athanasopoulos , Rob J. Hyndman , Nikolaos Kourentzes , Anastasios Panagiotelis
{"title":"Forecast reconciliation: A review","authors":"George Athanasopoulos , Rob J. Hyndman , Nikolaos Kourentzes , Anastasios Panagiotelis","doi":"10.1016/j.ijforecast.2023.10.010","DOIUrl":"10.1016/j.ijforecast.2023.10.010","url":null,"abstract":"<div><p>Collections of time series formed via aggregation are prevalent in many fields. These are commonly referred to as hierarchical time series and may be constructed cross-sectionally across different variables, temporally by aggregating a single series at different frequencies, or even generalised beyond aggregation as time series that respect linear constraints. When forecasting such time series, a desirable condition is for forecasts to be coherent: to respect the constraints. The past decades have seen substantial growth in this field with the development of reconciliation methods that ensure coherent forecasts and improve forecast accuracy. This paper serves as a comprehensive review of forecast reconciliation and an entry point for researchers and practitioners dealing with hierarchical time series. The scope of the article includes perspectives on forecast reconciliation from machine learning, Bayesian statistics and probabilistic forecasting, as well as applications in economics, energy, tourism, retail demand and demography.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 2","pages":"Pages 430-456"},"PeriodicalIF":7.9,"publicationDate":"2023-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169207023001097/pdfft?md5=22d99799cd25ab98a5a7ae5145f1d7e2&pid=1-s2.0-S0169207023001097-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139071694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Generalized Poisson difference autoregressive processes","authors":"","doi":"10.1016/j.ijforecast.2023.11.009","DOIUrl":"10.1016/j.ijforecast.2023.11.009","url":null,"abstract":"<div><p>This paper introduces a novel stochastic process with signed integer values. Its autoregressive dynamics effectively captures persistence in conditional moments, rendering it a valuable feature for forecasting applications. The increments follow a Generalized Poisson distribution, capable of accommodating over- and under-dispersion in the conditional distribution, thereby extending standard Poisson difference models. We derive key properties of the process, including stationarity conditions, the stationary distribution, and conditional and unconditional moments, which prove essential for accurate forecasting. We provide a Bayesian inference framework with an efficient posterior approximation based on Markov Chain Monte Carlo. This approach seamlessly incorporates inherent parameter uncertainty into predictive distributions. The effectiveness of the proposed model is demonstrated through applications to benchmark datasets on car accidents and an original dataset on cyber threats, highlighting its superior fitting and forecasting capabilities compared to standard Poisson models.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1359-1390"},"PeriodicalIF":6.9,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169207023001310/pdfft?md5=4c712880186f559616263672436b5004&pid=1-s2.0-S0169207023001310-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139071376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Forecasting emergency department occupancy with advanced machine learning models and multivariable input","authors":"","doi":"10.1016/j.ijforecast.2023.12.002","DOIUrl":"10.1016/j.ijforecast.2023.12.002","url":null,"abstract":"<div><p>Emergency department (ED) crowding is a significant threat to patient safety and it has been repeatedly associated with increased mortality. Forecasting future service demand has the potential to improve patient outcomes. Despite active research on the subject, proposed forecasting models have become outdated, due to the quick influx of advanced machine learning models and because the amount of multivariable input data has been limited. In this study, we document the performance of a set of advanced machine learning models in forecasting ED occupancy 24 h ahead. We use electronic health record data from a large, combined ED with an extensive set of explanatory variables, including the availability of beds in catchment area hospitals, traffic data from local observation stations, weather variables, and more. We show that DeepAR, N-BEATS, TFT, and LightGBM all outperform traditional benchmarks, with up to 15% improvement. The inclusion of the explanatory variables enhances the performance of TFT and DeepAR but fails to significantly improve the performance of LightGBM. To the best of our knowledge, this is the first study to extensively document the superiority of machine learning over statistical benchmarks in the context of ED forecasting.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1410-1420"},"PeriodicalIF":6.9,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0169207023001346/pdfft?md5=ce6f2f913f2f56e0a000145a128a4966&pid=1-s2.0-S0169207023001346-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139054325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An assessment of the marginal predictive content of economic uncertainty indexes and business conditions predictors","authors":"","doi":"10.1016/j.ijforecast.2023.11.010","DOIUrl":"10.1016/j.ijforecast.2023.11.010","url":null,"abstract":"<div><p><span>In this paper, we evaluate the marginal predictive content of a variety of new business conditions (BC) predictors as well as nine economic uncertainty indexes (EUIs) constructed using these predictors. Our predictors are defined as observable variables and latent factors extracted from a high-dimensional macroeconomic dataset, and our EUIs are functions of predictive errors from models that incorporate these predictors. Estimation of the predictors is based on a number of extant and novel machine learning methods that combine dimension reduction, variable selection, and shrinkage. When predicting 14 monthly </span>U.S. economic series selected from eight different groups of economic variables, our new indexes and predictors are shown to result in significant improvements in forecast accuracy relative to predictions made using benchmark models. In particular, inclusion of either BC predictors or EUIs often yields forecast accuracy improvements, while even greater predictive gains accrue when including both BC predictors and EUIs when forecasting real economic activity-type variables at shorter forecast horizons.</p></div>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"40 4","pages":"Pages 1391-1409"},"PeriodicalIF":6.9,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An assessment of the marginal predictive content of economic uncertainty indexes and business conditions predictors","authors":"Yang Liu, Norman R. Swanson","doi":"10.1016/j.ijforecast.2023.11.010","DOIUrl":"https://doi.org/10.1016/j.ijforecast.2023.11.010","url":null,"abstract":"<p>In this paper, we evaluate the marginal predictive content of a variety of new business conditions (BC) predictors as well as nine economic uncertainty indexes (EUIs) constructed using these predictors. Our predictors are defined as observable variables and latent factors extracted from a high-dimensional macroeconomic dataset, and our EUIs are functions of predictive errors from models that incorporate these predictors. Estimation of the predictors is based on a number of extant and novel machine learning methods that combine dimension reduction, variable selection, and shrinkage. When predicting 14 monthly U.S. economic series selected from eight different groups of economic variables, our new indexes and predictors are shown to result in significant improvements in forecast accuracy relative to predictions made using benchmark models. In particular, inclusion of either BC predictors or EUIs often yields forecast accuracy improvements, while even greater predictive gains accrue when including both BC predictors and EUIs when forecasting real economic activity-type variables at shorter forecast horizons.</p>","PeriodicalId":14061,"journal":{"name":"International Journal of Forecasting","volume":"249 1","pages":""},"PeriodicalIF":7.9,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139022366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}