基于条件生成对抗网络的深度点过程二次预测

结合深度神经网络和时序点过程的深度点过程模型在进行时间预测时，会因模型本身系统误差和数值计算精度不足而导致预测值序列中存在较大偏差。为提高预测精度并有效避免模型调优同时降低数值误差，建立一种基于条件生成对抗网络（CGAN）的深度点过程二次预测模型，在深度点过程初次预测值序列的基础上进行二次预测。假设初次预测偏差来自时序点过程分布上的差异，利用CGAN对分布的变换能力来修正初次预测值序列分布为原始时序点过程序列分布，从而降低预测值序列误差。在流程上，将初次预测值序列输入生成器生成伪值序列，将伪值序列与对应的真实值序列输入判别器中判别真假，经过对抗训练得到对初次预测值序列具备修正能力的生成器。同时，为增强CGAN对时序点过程数据的匹配度，在其结构上采用CGAN+LSTM的形式，同时改进损失函数为时序点过程Wasserstein距离的对偶形式及其1-Lipschitz约束。实验结果表明，该模型具有较高的时间预测准确度，二次预测值序列的均方误差相较初次预测值序列平均降低77%以上。

Second Prediction of the Deep Point Process Based on Conditional Generative Adversarial Network

The deep point process model that combines a deep neural network and time-series point process is often used for time prediction. However, large deviations in the prediction value series frequently occur because of the systematic error of the model itself and the insufficient accuracy of the numerical calculation. To improve the prediction accuracy, effectively avoid model tuning, and reduce numerical errors, a deep point process secondary prediction model based on a Conditional Generative Adversarial Network(CGAN) is established, and a second prediction is conducted based on the initial prediction value sequence of the deep point process. Based on the assumption that the initial prediction deviation derives from the difference in the process distribution of time-series points, the CGAN, with its ability to transform the distribution, is used to modify the initial prediction value sequence distribution to the original time-series point process sequence distribution, thereby reducing the prediction value sequence error. In this process, the initial predictive value sequence is input into the generator to generate a pseudo-value sequence. The pseudo-value sequence and corresponding real value sequence are then input into the discriminator to determine whether they are true or false. Following confrontation training, a generator that can correct the initial predictive value sequence is obtained. Simultaneously, to enhance the matching degree of the CGAN to the time-series point process data, a CGAN+LSTM structure is adopted, and the loss function is improved such that it becomes a dual form of the Wasserstein distance of the time-series point process and 1-Lipschitz constraint. Experimental results show that the model has a high time-prediction accuracy, and the Mean Square Error(MSE) of the second prediction value series is more than 77% less than that of the first prediction value series.