Theoretical Approach to Reduced Q-Matrix for Cognition Diagnosis

Abstract

The main issue of the Q-matrix theory for cognition diagnosis is how to find the reduced Q-matrix containing the all efficient items. In this paper, based on the attribute structure matrix transformation, a novel recognition function for an efficient item vector is proposed. Two fast algorithms, transformation algorithm and expansion algorithm for finding the reduced Q-matrix are proposed as well. Some important properties are also discussed.

Timelike pion form factor in lattice QCD

“…As indicated in [49], separating the two pion-operators can also be useful in the calculation of the I = 0 pion-pion scattering, where it reduces the noise dramatically from the disconnected diagram.…”