absence-of-ground searching selector

例句：

1. 1.The absence of ground truth data is a significant challenge for machine learning algorithms.
   缺乏地面真实数据是机器学习算法的一个重大挑战。
2. 2.The absence of ground truth data can lead to inaccurate predictions.
   缺乏地面真实数据可能导致预测不准确。
3. 3. The absence of ground truth data can hinder the development of new technologies.
   缺乏地面真实数据会阻碍新技术的发展。