SECAI Core · phase 3 of 15

Data cleaning

The process of ensuring that the data used in analysis is of a high-enough quality that it gives decision makers confidence in findings and the practice of transforming non-conforming data into acceptable shape.

The Explain card

Plain English
Data cleaning makes sure data is good enough to trust: fixing errors, filling or removing bad values, and reshaping non-conforming records into an acceptable form.
Example
Before training a fraud model, analysts strip out test transactions, correct mistyped currency codes and drop records with impossible dates.
Why it matters
Dirty data produces unreliable models, but cleaning is also a security step. It is where poisoned outliers, injected instructions and leaked secrets can be caught before they are learned.
Hook
Garbage in, garbage learned; clean before you train.

Where it sits in the deck

Phase 3: Data Fundamentals: Types, Pipelines, and Preparation

Models are only as good as their data — understand the raw material and the engineering that shapes it before covering how it flows or breaks.