A new-structure grey Verhulst model: Development and performance comparison

The structure defect of the traditional grey Verhulst model is a key factor leading to its unstable performance. A new-structure grey Verhulst model (N_Verhulst) was proposed by introducing a new non-homogeneous exponential function. The N_Verhulst model has a better structure and stronger modeling ability; Meanwhile, it overcomes the shortcomings of the traditional Verhulst model including parameter dislocation and unreasonable selection of initial values. Four typical cases were used to test the performance of N_Verhulst, and the simulation/prediction results of the new model were compared with the traditional Verhulst model and the Pearl model. Results showed that the N_Verhulst model had evidently superior performance to the traditional grey Verhulst model, which confirms that the structure development of the new model is reasonable and effective. (C) 2020 Elsevier Inc. All rights reserved.