I was pretty disappointed to learn that the METR metric isn't actually evaluating a model's ability to complete long duration tasks. They're using the estimated time a human would take on a given task. But it did explain my increasing bafflement at how the METR line keeps steadily going up despite my personal experience coding daily with LLMs where they still frequently struggle to work independently for 10 minutes without veering off task after hitting a minor roadblock.
On a diverse set of multi-step software and reasoning tasks, we record the time needed to complete the task for humans with appropriate expertise. We find that the time taken by human experts is strongly predictive of model success on a given task: current models have almost 100% success rate on tasks taking humans less than 4 minutes, but succeed <10% of the time on tasks taking more than around 4 hours. This allows us to characterize the abilities of a given model by “the length (for humans) of tasks that the model can successfully complete with x% probability”.
For each model, we can fit a logistic curve to predict model success probability using human task length. After fixing a success probability, we can then convert each model’s predicted success curve into a time duration, by looking at the length of task where the predicted success curve intersects with that probability.
[1] https://metr.org/blog/2025-03-19-measuring-ai-ability-to-com...
It makes perfect sense to use human times as a baseline. Because otherwise, the test would be biased towards models with slower inference.
If model A generates 10 tokens a second and model B generates 100 tokens a second, then using real LLM inference time puts A at a massive 10x advantage, all other things equal.