Module 10 Summary: Non-Parametric Thinking and Assumption Caution

What You Practised

You practised how to recognize when common tests need assumption caution and simpler alternatives.

Keep These Ideas

• Assumptions describe what must be reasonably true for a method to be trustworthy.
• Ordinal ratings have order, but the gaps between scores may not be equal.
• Ranking can be safer when data is skewed, ordinal, or strongly affected by outliers.

Writing Habit

The updated group appears to have higher satisfaction ranks, but because the data is ordinal, we should describe the direction cautiously and consider rank-based methods.

Before Moving On

You are ready for the next module when you can explain the module idea without reading the answer key and can name the main unsafe claim to avoid.