Averaging towards the mean

Photo accompanying the 'Averaging towards the mean' story

By Mick Barrett, Technical Lead · 27 Jul 2026

At an AI in the NDIS summit panel, the concern that came up most wasn't privacy, and it wasn't cybersecurity. It was simpler than that: as automated tools start drafting plan recommendations, they tend to "average towards the mean" — producing a plausible plan for a typical participant, when no participant is actually typical.

The panel — EY's Christina Larkin, former NDIA deputy CEO Anthony Vella, UTS's Darren Chua, and Jessica Martin of Bella Sláinte — pushed past the usual "human in the loop" reassurance. Their sharper question: when a model generates a budget, can the delegate who reviews it actually change it, or can they only ask the model to try again with different inputs? Nominal human oversight without real authority to override is exactly the failure mode the Robodebt scheme was built on. The panel's proposed standard was blunter than "human in the loop" — they called it a "meaningful human decision."

Whose data trains the model

Historical bias in the underlying data compounds the problem. One panellist pointed to a pattern well documented in health research generally: bias in health data tends to skew against women, because early medical research disproportionately studied male subjects. A planning model trained on that history doesn't correct the skew — it inherits it.

What changes in December

Privacy Act changes taking effect on 10 December 2026 will require disclosure whenever an automated system substantially informs a decision about access to services — a description that fits NDIS planning directly. One assurance specialist on the panel was candid that auditing a genuinely "black box" system for bias is hard to do properly, which raises the stakes on getting the disclosure right rather than treating it as a formality.

The NDIS Quality and Safeguards Commission is already building its own model in this space: an "intelligent risk engine," part of a $160 million program, intended to assess risk across participants, providers and workers alike. Not every voice on the panel was opposed to automation — one speaker made the case that it can cut administrative burden and enable continuous monitoring across an entire participant population, rather than the sampling that's standard today.

What the panel wants done before December

Timeline: New Framework Planning began 1 July 2026. The Commission's risk engine is expected by August 2026. Full participant transition to the new framework continues through October 2029.

Read the original coverage at abilitynews.org →