Inference for Forecasting Accuracy: Pooled versus Individual Estimators in High-dimensional Panel Data
高维面板中合并估计与个体估计的预测准确性推断
Panels with large time $(T)$ and cross-sectional $(N)$ dimensions are a key data structure in social sciences and other fields. A central question in panel data analysis is whether to pool data across individuals or to estimate separate models. Pooled estimators typically have lower variance but may suffer from bias, creating a fundamental trade-off for optimal estimation. We develop a new inference method to compare the forecasting performance of pooled and individual…