Correlation between the primary incursions in the west and the east.

We combine the western and eastern sector in one sector and apply varying leads between -3 and 3 years. A positive lead (predicting the incursions in the east) clearly increases the correlation. A negative lead (predicting the incursions in the west) has no significant effect.我们将东部与西部区域合并为单个区域，并设置取值范围为-3至3年的可变超前量。当超前量为正时（即用于预测东部区域的入侵事件），相关系数会显著提升；而当超前量为负时（即用于预测西部区域的入侵事件），则未产生显著影响。