How to check for counterbalancing

import pandas as pd

sample = pd.read_csv('./sampledata.csv')
sample.head(3)

	Movement	Island_Type	Island	Distance	Item	Sentence	Subj_id	List	Score
0	WH	whe	non	sh	1	Who thinks that Paul stole the necklace?	1	1	6
1	WH	whe	non	sh	2	Who thinks that Matt chased the bus?	1	1	2
2	WH	whe	non	sh	3	Who thinks that Tom sold the television?	1	1	3

Checking for counterbalancing (i.e., how many participants were assigned to each experimental list) on python is pretty simple - we can use nunique() function.

sample.groupby('List')['Subj_id'].nunique()

List
1    4
2    4
3    4
4    4
Name: Subj_id, dtype: int64

We can see that the counterbalancing was perfect - there are 4 participants in each list.