01 · Understand the idea
In simple words
Imagine a registration list where Pune appears as “Pune”, “pune” and “ Pune”. Cleaning can standardise these values so your analysis counts them consistently. But cleaning is not deleting everything unusual. Some unusual entries are real, and some missing entries have a meaning you need to preserve.
Two useful terms
Missing value: an entry that is absent or unknown. Duplicate: a repeated record according to a defined identity rule.
Build your understanding
Cleaning transforms raw observations into consistent inputs. Keep the raw data and document your decisions so another person can reproduce the result. Correct obvious formatting issues, but do not silently erase unusual values that might represent real cases.
Sign in to save your reading progress.
Sign in