How to Remove Duplicate Rows from a Survey Dataset

Learn how to remove duplicate rows from a survey dataset using Python and pandas. Clean your data by identifying and dropping repeated entries to ensure accurate analysis.




Duplicate rows in survey data occur when the same response is recorded more than once, often due to system errors or repeated submissions. 

These duplicates can distort analysis results and must be removed before processing.


Step 0: Load the Data

import pandas as pd
from google.colab import files

uploaded = files.upload()

file_name = list(uploaded.keys())[0]

df = pd.read_excel(file_name, skiprows=4)

df = df.dropna(axis=1, how='all')

df.head()



Step 1: Identify duplicates

df.duplicated().sum()

Step 2: Remove duplicates

df = df.drop_duplicates()
print(df)

Step 3: Confirm removal

df.duplicated().sum()
print(df)




Key point

Always deduplicate early in your pipeline to ensure each survey response is counted only once.


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