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arXiv · 2608.23732

Principal Component Analysis for a Mix of Stationary and Nonstationary Variables

James D. Hamilton·Xinwei Ma·Jin Xi
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Abstract

This paper develops a procedure for uncovering the common cyclical factors that drive a mix of stationary and nonstationary variables. The method does not require knowing which variables are nonstationary or the nature of the nonstationarity. An application to the FRED-MD macroeconomic dataset demonstrates that the approach offers similar benefits to those of traditional principal component analysis with some added advantages.

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James D. Hamilton, Xinwei Ma, Jin Xi. 2026-08-24. Principal Component Analysis for a Mix of Stationary and Nonstationary Variables. https://arxiv.org/abs/2608.23732

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