What is it?

Selection bias arises when a sample is not representative of the broader population, leading to skewed conclusions.

Bias may be unintentional.

Examples in Action

• Surveying only engaged users
  
• Testing changes on narrow segments
  
• Analysing incomplete datasets
  
• Excluding low-intent traffic
  

Typical Outcomes / Results

• Misleading insights
  
• Poor generalisation of results
  
• Increased decision risk
  
• Improved accuracy when addressed
  

This definition reflects standard statistical bias concepts.