The phenomenon of multiple transactions at each recording time is a common occurrence for high frequency financial data, due to heavy trading of the market and limitation of the recording mechanism. The situation has existed for a long time, but is getting more common in recent years due to...

In the literature, consistency of the estimates of the number of factors for both the discrete and continuous time factor models has been extensively studied recently. But the central limit theorem has long been unsolved. In this paper, alternative to the PCA-based approach, we construct a new...