Temperature changes variation, not factuality

Turning the temperature down makes a model more predictable. It does not make it more accurate.

Low temperature means it picks the most likely continuation more consistently, so you get the same answer each time. If that answer is wrong, you now get the same wrong answer reliably. It is a control over variation, frequently misunderstood as a control over truthfulness, and the confusion leads people to believe they have tuned away hallucination.

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