python - 负 'Start training from score'

Question

运行 lgb.cv 时，我有时会从日志中看到“从分数开始训练”后的负数。想知道这个数字到底是什么意思，单位是什么？是根据参数中指定的指标吗？以下是摘录:

[LightGBM] [Info] Total Bins 2767
[LightGBM] [Info] Number of data: 18600, number of used features: 1380
[LightGBM] [Info] Start training from score -5.186526
[LightGBM] [Info] Start training from score -5.320057
[LightGBM] [Info] Start training from score -5.215796

Answer 1

看起来您正在训练多类模型。 lightgbm 在二进制/多类建模中实际跟踪的“预测”是 log odds (或 logit)，而不是概率。这是您看到的初始分数。