My understanding is that base models are reasonably well calibrated but the RLHF and other tuning that turns them into chat assistants screws up the calibration.
There’s much that is lost but imo gpt-4-base would be borderline unusable for most of us compared to its descendants — perhaps even more so than GPT-3 davinci, at least relative to its time.
4 can be an absolute demonic hallucinating machine.
