In a single case from the examine cited by AP, when a speaker described “two different ladies and one woman,” Whisper added fictional textual content specifying that they “have been Black.” In one other, the audio mentioned, “He, the boy, was going to, I’m undecided precisely, take the umbrella.” Whisper transcribed it to, “He took an enormous piece of a cross, a teeny, small piece … I’m positive he didn’t have a terror knife so he killed a variety of folks.”
An OpenAI spokesperson advised the AP that the corporate appreciates the researchers’ findings and that it actively research the right way to scale back fabrications and incorporates suggestions in updates to the mannequin.
Why Whisper confabulates
The important thing to Whisper’s unsuitability in high-risk domains comes from its propensity to generally confabulate, or plausibly make up, inaccurate outputs. The AP report says, “Researchers aren’t sure why Whisper and comparable instruments hallucinate,” however that is not true. We all know precisely why Transformer-based AI fashions like Whisper behave this fashion.
Whisper is predicated on expertise that’s designed to foretell the following most definitely token (chunk of information) that ought to seem after a sequence of tokens offered by a person. Within the case of ChatGPT, the enter tokens come within the type of a textual content immediate. Within the case of Whisper, the enter is tokenized audio information.
The transcription output from Whisper is a prediction of what’s most definitely, not what’s most correct. Accuracy in Transformer-based outputs is often proportional to the presence of related correct information within the coaching dataset, however it’s by no means assured. If there’s ever a case the place there is not sufficient contextual data in its neural community for Whisper to make an correct prediction about the right way to transcribe a selected section of audio, the mannequin will fall again on what it “is aware of” in regards to the relationships between sounds and phrases it has discovered from its coaching information.