Automated Prompt Engineering for Forecasting
As part of a grant for the Foresight Institute, Metaculus has been running some experiments to make open-source research tools for forecasting bots and generally improve forecasting bot performance. This last sprint, I created an automated prompt optimizer to test whether some prompts do better than others. These are preliminary findings that we think can be useful to other researchers and bot makers. We plan to further test and improve this approach and ideally make the optimizer a publicly usable tool. Below is a snapshot of early findings. In the graphs below, the first bar represents the "perfect predictor" or the score of the community prediction (this is only perfect in the sense that it maximizes expected baseline score). The next bar is the Control Group (using the control prompt), and the final two bars are the top two scoring prompts using the training question set (collected when the prompt optimizer was run). Error bars denote 90% confidence intervals calculated using a t-t
Main Findings: Automated prompt optimization techniques create noticeable improvements in forecasting for some large language models, but not others. There were statistically significant forecasting improvements found when applying an optimizer to GPT-4.1-nano, moderate improvements to GPT-4.1, and no improvements for DeepSeek-R1. Tentatively, a prompt optimized for one model seems to work well for other models from the same provider and worse for models from other providers (though more testing is needed here). The best performing prompts for GPT-4.1 can be found here. These also…
related reading
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