This paper considers estimation and testing of multiple breaks that occur at unknown dates in multivariate long-memory time series. We propose a likelihood ratio based approach for estimating breaks in the mean and the covariance of a system of long-memory time series. The limiting distribution...

Certain literature that constructs a multifactor stock selection model adopted a weighted‑scoring approach despite its three shortcomings. First, it cannot effectively identify the connection between the weights of stock‑picking concepts and portfolio performances. Second, it cannot provide...

A factor model based covariance matrix is used to build a new form of Mahalanobis distance. The distribution and relative properties of the new Mahalanobis distances are derived. A new type of Mahalanobis distance based on the separated part of the factor model is defined. Contamination effects...