You may have heard of GPT2, a new language model. It has recently attracted attention from the general public as the foundation that published the paper, OpenAI, ironically refused to share the whole model fearing dangerous implications. Along the paper, they also published a manifesto to justify their choice: "Better Language Models and Their Implications". And soon a lot of media were publishing articles discussing the choice and its effectiveness to actually prevent bad implications. I am not here to discuss the ethical components of this choice but the actual performance of the model.
The model got my attention too and I downloaded the small model to play with. To be honest I am far from impressed by the results. Some times the first paragraph of the produced text appears to make sense, but nine times out of ten it is giberish by the first or the second sentence. Exemples given in the paper seems to be "Lucky" outputs, cherry picked by human hands. Overall, the paper may suffer from a very strong publication bias.
However most article we can read on the internet seems to take its powerfullness for granted. The MIT technology review wrote : "The language model can write like a human [...]", The Guardian wrote "When used to simply generate new text, GPT2 is capable of writing plausible passages that match what it is given in both style and subject. It rarely shows any of the quirks that mark out previous AI systems, such as forgetting what it is writing about midway through a paragraph, or mangling the syntax of long sentences.". The model appears generally qualified as a "breaktrough". These writings do not match my personnal experimentation as produced texts are rarely consistent / syntaxically correct.
My question is : whitout the release of the whole model for ethical reasons, how do we know if the model is really that powerfull ?