AI writing is measurably harder to read, and the training mix is part of the cause
AspireAI community · arXiv (Why is AI-generated language so hard to understand?)
*AI writing is measurably harder to read, and the training mix is part of the cause.*
Researchers at NYU and UT Austin profiled nine frontier models against human writing. Every one used more inanimate subjects with animate verbs and more rare word pairings than people do, and most used longer dependencies, more stacked nouns and more dropped relative markers.
The proposed cause is the objective. Math, code and reasoning tasks reward correctness and information density, while nothing rewards whether a human can parse the result, so post-training pushes models toward a register that reads well to other models and badly to us. Fine-tuning a model with a length penalty reproduced the drift.
The honest limit: nine models, and the cause is a tested hypothesis rather than a proven mechanism.
https://arxiv.org/abs/2610.29162
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