📊[DataCamp] Counting, Grouped summary statistics : groupby(), Pivot tables

📌 drop_duplicate method 

Removing duplicates is an essential skill to get accurate counts, because often you don't want to count the same thing multiple times. 

//중복 데이터 처리를 위한 메서드 

📌Counting categorical variables

Counting is a great way to get an overview of your data and to spot curiosities that you might not notice otherwise.

 

 

.value_counts()

.value_counts(normalize=True) 

// To calculate proportions, set normalize to True in .value_counts(). 

 

📌Grouped summary statistics

_ compare different groups 

 

 

 

 

that's too much work

 

.groupby("")[""].mean()

to get multiple statistics, use agg

 

 

 

 

 

many groups, many summaries 

 

📌그루핑하고, 컬럼 지정하고, Calculate

 

 

📌pivot tables : calculating group summary statistics 

 

 

 

 

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