Will Rogers phenomenon

What it is

Moving an item from one group to another can raise the average of both groups, making things look better though nothing changed.

Related

• Framing effect bias
  Changing how items are classified changes how the statistics look without changing reality.
• The problem with averages bias
  Both show how summary statistics can mislead: an average can hide the spread, and moving items between groups can raise both averages.

Appears in

• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly#58: Will Rogers phenomenon

References

• Wikipedia: Will Rogers phenomenon en.wikipedia.org
• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly en.wikipedia.org
• Wikipedia: List of cognitive biases en.wikipedia.org
• Wikipedia: Cognitive bias codex en.wikipedia.org

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