Using robust FPCA to identify outliers in functional time series, with applications to the electricity market

This study proposes two methods for detecting outliers in functional time series. Both methods take dependence in the data into account and are based on robust functional principal component analysis. One method seeks outliers in the series of projections on the first principal component. The other...

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Detalles Bibliográficos
Autores: Vilar, Juan M.|||0000-0002-5757-5919, Raña, Paula, Aneiros, Germán
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:168851
Acceso en línea:https://ddd.uab.cat/record/168851
Access Level:acceso abierto
Palabra clave:Functional data analysis
Functional principal component analysis
Functional time series
Outlier detection
Electricity demand and price
Descripción
Sumario:This study proposes two methods for detecting outliers in functional time series. Both methods take dependence in the data into account and are based on robust functional principal component analysis. One method seeks outliers in the series of projections on the first principal component. The other obtains uncontaminated forecasts for each data set and determines that those observations whose residuals have an unusually high norm are considered outliers. A simulation study shows the performance of these proposed procedures and the need to take dependence in the time series into account. Finally, the usefulness of our methodology is illustrated in two real datasets from the electricity market: daily curves of electricity demand and price in mainland Spain, for the year 2012.