Friday, January 06, 2017

The infrastructure of life 2 - Transparency

Part 2: Autonomous Systems and Transparency

In my previous post I argued that a wide range of AI and Autonomous Systems (from now on I will just use the term AS as shorthand for both) should be regarded as Safety Critical. I include both autonomous software AI systems and hard (embodied) AIs such as robots, drones and driverless cars. Many will be surprised that I include in the soft AI category apparently harmless systems such as search engines. Of course no-one is seriously inconvenienced when Amazon makes a silly book recommendation, but consider very large groups of people. If a truth such as global warming is - because of accidental or willful manipulation - presented as false, and that falsehood believed by a very large number of people, then serious harm to the planet (and we humans who depend on it) could surely result.

I argued that the tools barely exist to properly assure the safety of AS, let alone the standards and regulation needed to build public trust, and that political pressure is needed to ensure our policymakers fully understand the public safety risks of unregulated AS.

In this post I will outline the case that transparency is a foundational requirement for building public trust in AS based on the radical proposition that it should always be possible to find out why an AS made a particular decision.

Transparency is not one thing. Clearly your elderly relative doesn't require the same level of understanding of her care robot as the engineer who repairs it. Not would you expect the same appreciation of the reasons a medical diagnosis AI recommends a particular course of treatment as your doctor. Broadly (and please understand this is a work in progress) I believe there are five distinct groups of stakeholders, and that AS must be transparent to each, in different ways and for different reasons. These stakeholders are: (1) users, (2) safety certification agencies, (3) accident investigators, (4) lawyers or expert witnesses and (5) wider society.
  1. For users, transparency is important because it builds trust in the system, by providing a simple way for the user to understand what the system is doing and why.
  2. For safety certification of an AS, transparency is important because it exposes the system's processes for independent certification against safety standards.
  3. If accidents occur, AS will need to be transparent to an accident investigator; the internal process that led to the accident need to be traceable. 
  4. Following an accident lawyers or other expert witnesses, who may be required to give evidence, require transparency to inform their evidence. And 
  5. for disruptive technologies, such as driverless cars, a certain level of transparency to wider society is needed in order to build public confidence in the technology.
Of course the way in which transparency is provided is likely to be very different for each group. If we take a care robot as an example transparency means the user can understand what the robot might do in different circumstances; if the robot should do anything unexpected she should be able to ask the robot 'why did you just do that?' and receive an intelligible reply. Safety certification agencies will need access to technical details of how the AS works, together with verified test results. Accident investigators will need access to data logs of exactly what happened prior to and during an accident, most likely provided by something akin to an aircraft flight data recorder (and it should be illegal to operate an AS without such a system). And wider society would need accessible documentary-type science communication to explain the AS and how it works.

In IEEE Standards Association project P7001, we aim to develop a standard that sets out measurable, testable levels of transparency in each of these categories (and perhaps new categories yet to be determined), so that Autonomous Systems can be objectively assessed and levels of compliance determined. It is our aim that P7001 will also articulate levels of transparency in a range that defines minimum levels up to the highest achievable standards of acceptance. The standard will provide designers of AS with a toolkit for self-assessing transparency, and recommendations for how to address shortcomings or transparency hazards.

Of course transparency on its own is not enough. Public trust in technology, as in government, requires both transparency and accountability. Transparency is needed so that we can understand who is responsible for the way Autonomous Systems work and - equally importantly - don't work.

Thanks: I'm very grateful to colleagues in the IEEE global initiative on ethical considerations in Autonomous Systems for supporting P7001, especially John Havens and Kay Firth-Butterfield. I'm equally grateful to colleagues at the Dagstuhl on Engineering Moral Machines, especially Michael Fisher, Marija Slavkovik and Christian List for discussions on transparency.

Related blog posts:
The Infrastructure of Life 1 - Safety
Ethically Aligned Design
How do we trust our Robots?
It's only a matter of time

Sunday, January 01, 2017

The infrastructure of life 1 - Safety

Part 1: Autonomous Systems and Safety

We all rely on machines. All aspects of modern life, from transport to energy, work to welfare, play to politics depend on a complex infrastructure of physical and virtual systems. How many of us understand how all of this stuff works? Very few I suspect. But it doesn't matter, does it? We trust the good men and women (the disgracefully maligned experts) who build, manage and maintain the infrastructure of life. If something goes wrong they will know why. And (we hope) make sure it doesn't happen again.

All well and good you might think. But the infrastructure of life is increasingly autonomous - many decisions are now made not by a human but by the systems themselves. When you search for a restaurant near you the recommendation isn't made by a human, but by an algorithm. Many financial decisions are not made by people but by algorithms; and I don't just mean city investments - it's possible that your loan application will be decided by an AI. Machine legal advice is already available; a trend that is likely to increase. And of course if you take a ride in a driverless car, it is algorithms that decide when the car turns, brakes and so on. I could go on.

These are not trivial decisions. They affect lives. The real world impacts are human and economic, even political (search engine results may well influence how someone votes). In engineering terms these systems are safety critical. Examples of safety critical systems that we all rely on from time to time include aircraft autopilots or train braking systems. But - and this may surprise you - the difficult engineering techniques used to prove the safety of such systems are not applied to search engines, automated trading systems, medical diagnosis AIs, assistive living robots, delivery drones, or (I'll wager) driverless car autopilots.

Why is this? Well, it's partly because the field of AI and autonomous systems is moving so fast. But I suspect it has much more to do with an incompatibility between the way we have traditionally designed safety critical systems, and the design of modern AI systems. There is I believe one key problem: learning. There is a very good reason that current safety critical systems (like aircraft autopilots) don't learn. Current safety assurance approaches assume that the system being certified will never change, but a system that learns does – by definition – change its behaviour, so any certification is rendered invalid after the system has learned.

And as if that were not bad enough, the particular method of learning which has caused such excitement - and rapid progress - in the last few years is based on Artificial Neural Networks (more often these days referred to as Deep Learning). A characteristic of ANNs is that after the ANN has been trained with datasets, any attempt to examine its internal structure in order to understand why and how the ANN makes a particular decision is impossible. The decision making process of an ANN is opaque. Alphago's moves were beautiful but puzzling. We call this the black box problem.

Does this mean we cannot assure the safety of learning autonomous/AI systems at all? No it doesn't. The problem of safety assurance of systems that learn is hard but not intractable, and is the subject of current research*. The black box problem may be intractable for ANNs, but could be avoided by using approaches to AI that do not use ANNs.

But - here's the rub. This involves slowing down the juggernaut of autonomous systems and AI development. It means taking a much more cautious and incremental approach, and it almost certainly involves regulation (that, for instance, makes it illegal to run a driverless car unless the car's autopilot has been certified as safe - and that would require standards that don't yet exist). Yet the commercial and political pressure is to be more permissive, not less; no country wants to be left behind in the race to cash in on these new technologies.

This is why work toward AI/Autonomous Systems standards is so vital, together with the political pressure to ensure our policymakers fully understand the public safety risks of unregulated AI.

In my next blog post I will describe one current standards initiative, towards introducing transparency in AI and Autonomous Systems based on the simple principle that it should always be possible to find out why an AI/AS system made a particular decision.

The next few years of swimming against the tide is going to be hard work. As Luke
Muehlhauser writes in his excellent essay on transparency in safety-critical systems "...there is often a tension between AI capability and AI transparency. Many of AI’s most powerful methods are also among its least transparent".

*some, but nowhere near enough. See for instance Verifiable Autonomy.

Related blog posts:
Ethically Aligned Design
How do we trust our Robots?
It's only a matter of time