Statistical Inference for EveryoneXYZ Homework Edition

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14.3 Qualitative labels to probability values

Rough guide for the conversion of qualitative labels to probability values used throughout the book.

termprobability
virtually impossible1/1,000,000
extremely unlikely0.01 (i.e. 1/100)
very unlikely0.05 (i.e. 1/20)
unlikely0.2 (i.e. 1/5)
slightly unlikely0.4 (i.e. 2/5)
even odds0.5 (i.e. 50-50)
slightly likely0.6 (i.e. 3/5)
likely0.8 (i.e. 4/5)
very likely0.95 (i.e. 19/20)
extremely likely0.99 (i.e. 99/100)
virtually certain999,999/1,000,000

Adapted from Statistical Inference for Everyone, by Brian Blais (Bryant University), licensed under CC BY-SA 4.0 (dual-licensed under the GNU FDL 1.2 or later; this adaptation uses the CC BY-SA grant). Changes were made; this adaptation is distributed under the same license. License: CC-BY-SA-4.0.

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