Show pageOld revisionsBacklinksFold/unfold allBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ====== SQL z-score 구하기 ====== SQL을 통해서 표준화점수 구하기 $$ z-score = \frac{X_i - Mean(X)}{std(X)} $$ * Key : 평균, 표준편차는 하나의 값이니까, croos join으로 해결 group by 처럼 되면 안됨. <code sql> SELECT (T1.values - stats.average) / stats.s AS zvalue FROM [TABLE] T1 cross join (select sttdev(values) as s, avg(values) as average from [TABLE]) stats; </code> {{tag>data_analysis:sql z-score z점수 표준화점수}} ~~DISCUSSION~~ data_analysis/sql/z-score.txt Last modified: 2025/07/07 14:12by 127.0.0.1