Min Lin(林敏); Han Lin
Journal of Business & Economic Statistics (JBES)
https://doi.org/10.1080/07350015.2026.2707220
JEL CLASSIFICATION
C23; C13; C12

ABSTRACT
The Mixed Data Sampling (MIDAS) approach provides a flexible framework for incorporating mixed-frequency data into econometric models. In this article, we introduce the MIDAS framework into a panel data model and derive the asymptotic properties of the NLS estimator under a joint asymptotic framework where both N and T tend to infinity, allowing for heteroscedasticity and arbitrary correlation within each individual. To facilitate valid inference, we construct robust heteroscedasticity- and autocorrelation-consistent (HAC) covariance estimators. We also analyze the asymptotic bias and variance of the LS estimator based on pre-specified aggregation weights. In addition, we propose a Wald test for the null hypothesis of equal weights and a supremum-type Wald test to address the unidentified nuisance parameter problem. The theoretical results are evaluated via an extensive Monte Carlo simulation study and an empirical application.
KEYWORDS
Autocorrelation; Heteroskedasticity; Mixed data sampling; Panel data model; Supremum-type Wald test