DebateLab@KIT computational philosophy projects
Thinking Aloud: Dynamic Context Generation Improves Zero-Shot Reasoning Performance of GPT-2
Thinking Aloud is well-studied and widely used meta-cognitive strategy to improve one’s reasoning skill. In our paper “Thinking Aloud: Dynamic Context Generation Improves Zero-Shot Reasoning Performance of GPT-2” we explore whether neural language models like GPT-2 can similarly (self-)improve their performance on a reasoning task by elaborating the problem before providing an answer.
We create a simple multi-hop deductive inference task and evaluate various “elaboration strategies,” e.g., by including different sample elaborations in the prompt, or by querying the model iteratively.
Our main findings are:
- GPT-2 seems to follow a simple syntactic heuristic when solving our multi-hop inference task. This heuristic leads the model astray if the problem is sufficiently hard, causing fallacious reasoning and systematic bias.
- Self-generated problem elaborations can de-bias the system and increase accuracy by up to 8% for hard problems.
- The effectiveness of a given problem elaboration seems to depend on how well the elaboration coheres with the original problem description. (Most-faithful elaborations boost accuracy by up to 24%.)
As a follow-up to this study, we’re thinking about how a neural language model might acquire (be taught) the general competence to effectively and sensibly elaborate on a given problem.
Post Scriptum 09/05/2022: Google has recently published results for its latest Large Language Model called PaLM – a language model more than two orders of mangintude larger than the GPT-2 model we’ve been using in our Thinking Aloud study (175B > 1.5B parameters). It’s fascinating to see that PaLM exhibits clearly and precisly the skill we’ve been testing for: PaLM has a few-shot ability to generate sensible “chains of thought” in response to problems, and can use these auto-generated texts for improving the accuracy of its answers (Wei et al. 2022).
Post Post Scriptum 03/06/2022: While Wei et al. (2022) prove, as mentioned above, the capability of LLMs’ few-shot ability of effective problem elaboration, Kojima et al. (2022) demonstrate that chain of thought (CoT) prompting is also effective in a zero-shot setting (with a 175B parameter model). :-)