Realistic AI engineering scenarios with reference solutions and problem-specific grading rubrics.
groupby · Datetime handling · Deduplication · pandas
merge · Deduplication · Data quality · Join semantics
Time series · GroupBy · Reindexing · Data leakage
pivot / unstack · Reshaping · Categorical data · GroupBy
str.extract · Regular expressions · Data cleaning · Missing data
read_csv · Filtering · GroupBy · Data cleaning
GroupBy · Time series · Rolling windows · Feature engineering
GroupBy · Time series · cumsum · Feature engineering
sort_values · GroupBy · Ranking · Tie-breaking
Cohort analysis · Period arithmetic · GroupBy · Dense reindexing
merge_asof · Data leakage · Feature stores · Time series