Human biases cause problems for machines trying to learn chemistry

They found that models trained on a small randomised sample of reactions outperformed those trained on larger human-selected datasets. The results show the importance of including experimental results that people might think are unimportant when it comes to developing computer programs for chemists. Machine learning models are a valuable tool in chemical synthesis, but they're trained on data from the literature where positive results are favoured, whereas the dark reactions – the experiments that were tried but didn't work – are usually left out. 'Including these failures is essential for generating predictive machine learning models,' says Joshua Schrier of Fordham University, US, who was part of a team that studied hydrothermal syntheses of amine-templated metal oxides and found that biases were introduced into the literature by people's choices of the reaction parameters. 'We considered extra dark reactions – a class of reactions that humans don't even attempt, not because of scientific or practical reasons, but simply because it's humans who make the decisions,' Schrier says.