Bias number 27 is known as the conjunction fallacy. This is a cognitive bias that arises when we make assumptions about the occurrence of more than one condition, such as a personality trait.
For the statisticians amongst us, this is an interesting cognitive bias because it assumes that specific conditions are more probable when they occur together over the occurrence of a single condition. This is statistically improbable, and yet our thought processes, relying less on fact and more on assumption, will infer otherwise.
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