Measures of spread: variance, standard deviation

This sub-topic covers how to quantify the dispersion of data values around the mean using variance and standard deviation, the most widely used measures of spread for numerical data. You will learn hand calculation, GDC use, and interpretation for exam questions.

📖Study Guide

In-depth bilingual notes with worked past paper examples.

✍️Practice Exam

Timed practice questions with mark scheme grading. Coming soon.

🎴Flashcards

Spaced repetition for key concepts and definitions. Coming soon.

📊Visualizer Coming Soon

Interactive plots and diagrams to build intuition. Coming soon.

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