Blazars can be divided into two subtypes, flat spectrum radio quasars (FSRQs) and BL Lac objects, which have been distinguished phenomenologically by the strength of their optical emission lines, while their physical nature and relationship are still …

We propose a $K$-sparse exhaustive search (ES-$K$) method and a $K$-sparse approximate exhaustive search method (AES-$K$) for selecting variables in linear regression. With these methods, $K$-sparse combinations of variables are tested exhaustively …

We develop an approximation formula for the cross-validation error (CVE) of a sparse linear regression penalized by $\ell_1$-norm and total variation terms, which is based on a perturbative expansion utilizing the largeness of both the data …

The author gives an algorithm to search the structure of a stochastic models with hidden variable. The author have shown the algorithm to find the hidden structure of the Hidden Markov Model and in this article, the algorithm is applied for one of …

In order to categorize a set of data which consists of some categories, it is important to know the probability distribution of the data of each category. Using these probability distributions, one can classify the data. In most cases, such as speech …

The author proposes an algorithm to define a structure of a HMM (hidden Markov model). HMMs are widely used in the speech recognition systems and at that time structures are usually determined according to the heuristic knowledge. In this article …