Z-score

Lesson in the Python for Data Analysis Roadmap · Stage 10: Exploratory Data Analysis

Last updated 14 September 2026

What is Z-score?

A Z-score measures how many standard deviations a value is from the mean. Values with a Z-score above 3 or below −3 are commonly flagged as outliers. Z-scores are calculated using scipy.stats.zscore() or manually and work best when the data is approximately normally distributed.

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Z-score: common questions

Can I learn Z-score in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Z-score in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Z-score tutorial for beginners?

It is lesson 72 of 112 in the free Python for Data Analysis roadmap, in stage 10, Exploratory Data Analysis. If you are new to Python for Data Analysis, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.