Pandas 按多列分组并计算标准差

Question

我有一个 pandas 数据框，其中包含来自多个赛季和球队的 NBA 篮球运动员的统计数据。它看起来像这样：

Year         Team          Player            PTS/G 
2018         Lakers        Lebron James      27.6
2018         Lakers        Kyle Kuzma        10.3
2019         Rockets       James Harden      25.5
2019         Rockets       Russel Westbrook  23.2

我想创建一个名为 'PTS Dev' 的新列，它是每个团队和年份的 PTS/G 的标准差。然后，我计划根据该偏差分析玩家的位置。这是我计算该列的尝试：

final_data['PTS Dev'] = final_data.groupby('Team', 'Year')['PTS/G'].std()

Answer 1

使用groupby with transform

final_data['PTS Dev'] = final_data.groupby(['Team', 'Year'])['PTS/G'].transform('std')
final_data
Out[9]: 
   Year     Team            Player  PTS/G    PTS Dev
0  2018   Lakers      Lebron James   27.6  12.232947
1  2018   Lakers        Kyle Kuzma   10.3  12.232947
2  2019  Rockets      James Harden   25.5   1.626346
3  2019  Rockets  Russel Westbrook   23.2   1.626346

Pandas 按多列分组并计算标准差

Pandas Group By Multiple Colums and Calculate Standard Deviation

standard-deviation

pandas-groupby