# Working with numerical data

ML practitioners spend far more time evaluating, cleaning, and transforming data than building models. Data is so important that this course devotes three entire units to the topic:

This unit focuses on numerical data, meaning integers or floating-point values that behave like numbers. That is, they are additive, countable, ordered, and so on. The next unit focuses on categorical data, which can include numbers that behave like categories. The third unit focuses on how to prepare your data to ensure high-quality results when training and evaluating your model.

Examples of numerical data include:

• Temperature
• Weight
• The number of deer wintering in a nature preserve

In contrast, US postal codes, despite being five-digit or nine-digit numbers, don't behave like numbers or represent mathematical relationships. Postal code 40004 (in Nelson County, Kentucky) is not twice the quantity of postal code 20002 (in Washington, D.C.). These numbers represent categories, specifically geographic areas, and are considered categorical data.

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{"lastModified": "Last updated 2024-08-13 UTC."}