Estimates the number of factors by minimising an information criterion over sub-samples of the data.
Currently the three information criteria proposed in Alessi, Barigozzi and Capasso (2010) (ic.op = 1, 2, 3)
and their variations with logarithm taken on the cost (ic.op = 4, 5, 6) are implemented,
with ic.op = 5 recommended as a default choice based on numerical experiments.
abc.factor.number(x, covx = NULL, q.max = NULL, center = TRUE)a list containing
the mimimiser of the chosen information criteria
input time series matrix, with each row representing a variable
covariance of x
maximum number of factors; if q.max = NULL, a default value is selected as min(50, floor(sqrt(min(dim(x)[2] - 1, dim(x)[1]))))
whether to de-mean the input x row-wise
See Alessi, Barigozzi and Capasso (2010) for further details.
Alessi, L., Barigozzi, M., & Capasso, M. (2010) Improved penalization for determining the number of factors in approximate factor models. Statistics & Probability Letters, 80(23-24):1806–1813.