... to reduce the perturbation of the original data. Finally, in order to effectively find the optimal fraction accumulation generation coefficient, the particle swarm optimization (PSO) is used to determine the emerging coefficient. Findings Experimental results show that FIEGM(1, N) outperforms other grey...

... the discretization error from the differential equation to its discrete forms. Then incorporating the conformable fractional accumulation into the discrete NGBM(1,1) model is carried out to further improve the predictive performance. Finally, in order to effectively seek the emerging coefficients, namely, fractional...