本文对结构性变化的旅游需求进行研究,基于带有外生变量的向量自回归(VARX)模型,提出了一种分段组合预测的方法。与既有研究普遍采用的基于完整数据集构建组合预测模型不同,本文创新性地将时间因素纳入组合预测考量,通过将不同时间段的变量视为独立的单元,构建出分段时间序列数据集的组合预测模型。该方法以游客的网络搜索行为作为外生变量用于预测旅游人数,并捕捉这些外生变量在不同时间节点上对旅游人数产生的差异化影响,特别是在新冠疫情等突发冲击下的动态变化。实证结果显示,VARX模型的分段组合在预测中国出境旅游人数时展现出更高的准确性,其预测精度因考虑了外生变量在不同时间段的特异性影响而得以提升。事后分析进一步显示,特别是针对2024年中国出境旅游趋势的外样本预测结果,随着新冠疫情影响的逐渐消退及全球旅游市场的逐步复苏,中国出境旅游人数将呈现积极向上的增长态势。这一结论与现有公开文献中的趋势分析相吻合,进一步印证了本文预测方法的实践应用价值。

Recent advances on time series forecasting mainly focus on improving the forecasting models themselves. However, when the time series data suffer from potential structural breaks or concept drifts, the forecasting performance might be significantly reduced. In this paper, we introduce a novel approach called Optimal Starting Point Time Series Forecast (OSP-TSP) for optimal forecasting, which can be combined with existing time series forecasting models. By adjusting the sequence length via leveraging the XGBoost and LightGBM models, the proposed approach can determine the optimal starting point (OSP) of the time series and then enhance the prediction performances of the base forecasting models. To illustrate the effectiveness of the proposed approach, comprehensive empirical analysis have been conducted on the M4 dataset and other real world datasets. Empirical results indicate that predictions based on the OSP-TSP approach consistently outperform those using the complete time series dataset. Moreover, comparison results reveals that combining our approach with existing forecasting models can achieve better prediction accuracy, which also reflect the advantages of the proposed approach.