Hippocampus's Garden

If you want to use a custom loss function with a modern GBDT model, you'll need the first- and second-order derivatives. This post shows how to implement them, using LightGBM as an example

How come ROC-AUC is equal to the probability of a positive sample ranked higher than negative ones? This post provides an answer with a fun example.

袋麺で油そばを作りたくて試行錯誤した結果をまとめました。Optunaは使用しておりません。

Transformer has undergone various application studies, model enhancements, etc. This post aims to provide an overview of these studies.

This post introduces how to sample groups from a dataset, which is helpful when you want to avoid data leakage.

『リーダブルコード』のまとめと感想です．

なぜ結婚後の名字をマリオカートで決めることになったのか、また選択的夫婦別姓について書きます。

This post compares the behaviors of different feature importance measures in tricky situations.

This post introduces the Pandas method of `query`, which allows us to query dataframes in an SQL-like manner.

『効果検証入門』のまとめと感想です．関連書『測りすぎ』の感想も．