Category Archives: General

How to detect AI snake oil

This is a great set of slides by Arvind Narayanan of Princeton, on the dangers of assuming that current AI, powerful though it is, can make much in the way useful predictions when it comes to complex social factors.

His key claim:

For predicting social outcomes, AI is not substantially better than manual scoring using just a few features.

It would be nice if he had more than one example in the talk, but the one he’s picked is a good one, and these are very readable slides.

The question UK voters should be asking this morning

Well, we live in interesting times! The key emotion most of us felt, I imagine, on hearing the election results, was one of amazement, closely followed by joy, anger, disappointment etc depending on your political persuasion. Almost nobody expected this result, and though the polls had been predicting a probable Conservative win, it was expected to be a modest one, and their lead had been diminishing in recent weeks. So this was fairly astonishing.

If you are as surprised as I am this morning, and as I imagine most of my acquaintances will be, whatever their political persuasion, then I think there’s a key question to ask yourself:

What is it about my social circle (both online and offline), my sources of news, my breadth of reading, my understanding of politics, my grasp of statistics, or my knowledge of history, that caused me to be so mistaken about the country’s mood? And how should I rectify that?

Capitalism and Machine Learning

You may have wondered why AI companies, like DeepMind, who specialise in machine learning systems, seem to devote so much time to creating systems that can play chess, or Go, or Space Invaders. Why don’t they do something more useful?

Well, part of the answer is that a machine, like a child, can only learn the right things if you give it very clear feedback about how it’s doing. And the key thing about games is that they have scores, which quickly give you this simple, unambiguous, reinforcement. And they do so without much delay, and in particular without much interpretation or interference by fallible humans.

Compare that with, say, recognising that a dot on an X-ray taken in one hospital eventually became a tumour which was diagnosed two years later by a physician in another clinic inspecting an MRI image taken from another angle. The key problem, in the majority of machine learning systems, is not the one of noticing the dot or even distinguishing it from other dots. It’s the one of assigning it a score, when there are so many complicated factors in the way.

I was thinking of this when reading David Brooks’s opinion piece in the NYT: “I Was Once a Socialist. Then I Saw How It Worked.” (This is behind a partial paywall, but you can probably read it with some carefully-placed clicks or a free subscription.)

Extract:

Socialist planned economies — the common ownership of the means of production — interfere with price and other market signals in a million ways. They suppress or eliminate profit motives that drive people to learn and improve.

It doesn’t matter how big your computers are, the socialist can never gather all relevant data, can never construct the right feedback loops. The state cannot even see the local, irregular, context-driven factors that can have exponential effects. The state cannot predict people’s desires, which sometimes change on a whim. Capitalism creates a relentless learning system. Socialism doesn’t.

Lots of good stuff in here, and most of it, no doubt, is not new, but I don’t normally spend more time than I have to thinking about politics!

All of these leaders understood that the answer to the problems of capitalism is wider and fairer capitalism.

But capitalism, like all human systems, is always unbalanced one way or another. Over the last generation, capitalism has produced the greatest reduction in global income inequality in history. The downside is that low-skill workers in the U.S. are now competing with workers in Vietnam, India and Malaysia. The reduction of inequality among nations has led to the increase of inequality within rich nations, like the United States.

These problems are not signs that capitalism is broken. They are signs that we need more and better capitalism.

A big mistake those of us on the conservative side made was to think that anything that made the government bigger also made the market less dynamic. We failed to distinguish between the supportive state and the regulatory state.

The supportive state makes better and more secure capitalists. The Scandinavian nations have very supportive welfare states. They also have very free markets. The only reason they can afford to have generous welfare states is they also have very free markets.

(Emphasis mine)

Good reading, given the current rhetoric of the UK political parties as we approach our election on Thursday.

Renewing your sense of pride?

The UK doesn’t have much to be proud of at present, but I think we can rightly feel pleased with ourselves about this:

In the third quarter of 2019, we generated 1% of our electricity from coal, 20% from nuclear, 38% from oil and gas. And 40% from renewables.

More details on this page. Extract:

This is the first-ever quarter where renewables outpaced fossil fuels since the UK’s first public electricity generating station opened in 1882. It is another symbolic milestone in the stunning transformation of the UK’s electricity system over the past decade.

Zipping along to the plumber

I’ve often bemoaned the fact that so many garments, bags, etc are spoiled by the failure of their zipper; an event which turns something previously warm and cozy into a source of frustration. But unstitching the zip and installing a new one is often tricky and therefore time-consuming or expensive; generally not worthwhile on an old garment or bag.

Not all zipper failures are terminal, however; many can obviously be repaired with a bit of jiggling, but many more can probably also be fixed with some cunning techniques. A retweet by my friend Lyndsay got me thinking along these lines, and I went and searched YouTube for ‘zipper repair’, and you can find a wealth of tips and suggestions: almost anything except significant loss of teeth can be fixed without the zipper needing to be replaced.

Here are some basic tips to get started:

But for a larger selection of example fixes, you might want to browse this playlist from UCAN, a US-based zipper company. Lots of good stuff there.

OK, so what’s that bit in the title about plumbers?

Well, it’s not, I admit, a very obvious connection, except that if you’re in the mood for fixing things yourself, I’ve become a fan of another source of YouTube wisdom. There’s a retired plumber named Al who has a great set of videos about how to fix various plumbing issues: what to do if your kitchen mixer tap is leaking into the cupboard below, suggestions for fixing leaking gutters, how to use compression couplings to join copper pipes…

Al has uploaded hundreds of videos on all sorts of topics, not just plumbing, but I do like his plumbing ones: they’re completely unpretentious, unbiased chunks of accumulated wisdom and it’s just the sort of thing YouTube does well.

Reflections on Inflections

“I expect our sales”, says the marketing manager confidently, “to have an inflection point in Q1 next year”.

This is a pet peeve of mine. I’ve often heard sales and marketing types, and even economists and scientists who should know better, use ‘inflection point’ simply to mean ‘a sudden change in the direction I’d prefer’. Perhaps they think an inflection point is the sharp bend in a hockey-stick-type curve, or the lowest point on a line that is about to turn upwards.

In fact, an inflection (or occasionally ‘inflexion’) point on a graph is technically where the second derivative is zero and changes sign: i.e. where the gradient changes from decreasing (or increasing) to increasing (or decreasing). Another way to think of it is that, viewed from the side, the line changes from concave to convex, or vice versa.

So, typically, an inflection point looks like this:

But, when touting your sales figures, remember that this is also an inflection point:

And so is this:

Doing a quick search, I came across an article from Thoughtworks all about inflection points and how they are important to your business. Sadly, they get it completely wrong.

As a technology leader, a portion of your analysis should revolve around determining inflection points, the critical phases of transitions along a technology’s journey from an abstract idea to maturity.
Inflection points are the points at which a product becomes a trend (something that will be used by a critical mass and therefore likely to drive value) instead of a fad (something that will fizzle out).

And here’s their illustration:

But you, gentle reader, know better. That’s not an inflection point! This is an inflection point:

And if your strategy was to catch technologies there, I think you’d write a rather different article.

Where the streets have many names

Here’s a pretty map of Chicago, produced by Erin Davis:

(Click for a larger image)

The colours come from the street suffixes: Green for ‘roads’, yellow for ‘streets’, etc. It’s an interesting commentary on naming trends and the historical development of the city.

Erin’s done many more, too, which you can find on her site here, and more recently including more global cities, here.

There clearly haven’t been many new ‘streets’ in London for some time…

Perchance to tweet?

The spellchecker on my iPhone 6 doesn’t know the word ‘perchance’! I desired to use it in a perfectly ordinary sentence today, and found I had to spell it out, confirming my intent with the leftmost of the available buttons.

Maybe ’tis only acceptable when followed by “to dream”? Or embedded in a flow of iambic pentameter?
In either case, you will agree this is a serious flaw, which is, no doubt, addressed in the latest version of the operating system.

Sadly, my iPhone is deemed too archaic to be able to run that version! Or perhaps it’s the owner…

Remember the pre-Twitter world?

In the beginning, Twitter only allowed messages to be 140 characters long. This was because SMS text messages were a common way of posting, and sometimes receiving, tweets, and they were limited to 160 characters; allow 20 characters for a username, and 140 is all you have left: about 20 words.

Two years ago, Twitter expanded the maximum length from 140 to 280 characters, though they said soon afterwards that this hadn’t actually made much difference to the average tweet length. It did, however, reduce the number of abbreviations – remember b4 this, when everything was gr8? Thank heavens we don’t have so much of that now, though I suspect an improvement in phone keyboards also played a significant role in the change.

Last night, I was contemplating the new trend for people to write long spiels using Twitter ‘threads’; typically one sentence per tweet. Sometimes you see them with ‘1/17’, ‘2/17’ etc after each post. It works, but it really seems as if Twitter is being stretched beyond its design!

I suppose the alternative would be to use Facebook, but who wants to do that?

So I was feeling a bit nostalgic for blogs and RSS feeds. Just imagine how good social media would be if:

  • (a) you could decide whether or not people could post comments on your posts,
  • (b) you could make the posts as long or as short as you liked, in whatever style you liked
  • (c) your readership would decide on whether the quality of your content justified the effort of reading it
  • (d) you could decide whom to follow, and only see their posts
  • (e) you got to see all of their posts, if you wanted, without an algorithm deciding which ones you should read
  • (f) advertising was completely optional

Doesn’t that sound good? Well, that’s what we had in 2005. 🙂

Don’t get me wrong, I do use Twitter, and I’ve had an account for over 11 years now, but I’ve had a blog, and read other blogs, for much longer, and if I ever had to make a choice between losing Twitter or losing my RSS feeds, I’d soon be waving bye-bye to the little blue bird.

But then I realised this was crazy thinking. Imagine if you had to show you could write a whole sentence before you could be elected President? Or even a paragraph just to announce a major change in policy? I guess nothing would ever be accomplished…

What you need to know about 5G coverage

I once went to a talk by Ben Goldacre, in which he said he was going to get a T-shirt printed. This was because he seemed to be giving the same response to lots of questions recently, and it would be easier if people could just read the answer as they walked up to him. The text would say, “I think you’ll find it’s a bit more complicated than that.”

It was a throwaway comment, but I often think of it, most recently as the British mobile phone networks start rolling out 5G and (because they spent so much on licensing the spectrum) are being very energetic about telling us how wonderful it is.

Yes, 5G can be faster. Potentially much faster. That’s the main marketing push, of course: you can play games more interactively and watch higher-quality videos more quickly. Marketing people like simple numbers. Which is fine, but it’s just an incremental change to 4G, and many people, including me, find it hard to get very excited about that.

I’m far from being an expert on mobile networks, but I have some friends who are, and I’m slowly learning that there are lots of other aspects to consider. Here are a few lesser-known facts about 5G:

  • First, it makes it easier to add large numbers of devices to the network, for Internet-of-things-type applications. If you’re a farmer deploying thousands of soil-humidity sensors across your fields, for example, or a council putting environment-monitoring sensors on every lamppost, 4G wouldn’t be a very viable way to do it. 5G might be, though whether it will really be an affordable one remains to be seen. It probably won’t compete with technologies like LoRaWAN and SigFox for these low-bandwidth applications, where you often want battery-powered devices with a battery life measured in years. But no doubt it will find a niche in due course.
  • One of the more interesting characteristics, for me, is the potential for much lower-latency connections. When your phone asks, say, a DNS server for the address of ‘statusq.org’, the amount of data actually being transmitted is small, and won’t be affected much by a big increase in bandwidth. What’s important is the round -trip time, and 5G offers the potential for this to be much smaller. (If you just want to send a postcard and get a reply, it doesn’t matter how big the postal service’s van’s are, but it does matter how fast they drive them to the destination and back.) This will affect how natural your video calls feel, because you won’t be talking over each other so much. It may one day affect how quickly your autonomous vehicle knows that a car ahead of you has slammed on its brakes. But in the meantime it will also speed up much more trivial things, like how quickly your email program can check whether you have new email.
  • There are several different bits of radio spectrum – three main ones – that can be used by 5G. This is actually really important, and ordinary users need to be educated about it. Why? Well, as a rough approximation, it’s a basic law that higher-frequency radio signals can transfer more information, but over shorter distances. In the UK, we currently use the middle chunk of 5G spectrum, which is a sensible compromise, but gives you neither the highest speeds, nor the biggest coverage. In some parts of the USA, they are able to use the highest frequencies already, which means you can find YouTube videos of people getting phenomenal data rates, but if you go out and spend a thousand quid on a 5G phone here, you’ll never match them. Not for the next few years, anyway. More importantly, in my opinion, there is a lower-frequency range (below 1Ghz) which will allow transmission over greater distances — which is good for coverage — but at lower speeds. Here’s the important thing: When this becomes available in the UK, it will allow the phone companies truthfully to claim substantial geographic 5G coverage. But it’s also important to note that connections in this spectrum will be slower than 4G. So if you are mostly (like me) in an area that hovers between 3G and 4G, and you hear that – hurrah! – 5G coverage is finally available in your area, you may be very excited and go and spend lots of money on a 5G phone, only to find that things get slower. You have been warned.

So, yes, 5G is generally a good thing, or will be in a couple of years. And it has key advantages other than just streaming Netflix in higher resolution.

But perhaps the best news, if your family and friends start asking you about it, is that Ben did actually go ahead and create those T-shirts.

Gardening philosophy

A man’s reach should exceed his grasp
Or what’s a hedgetrimmer extension handle for?

The Digital What?

A good friend called me today, just to check I was OK, because I hadn’t posted on my blog for some time! He’s right — it’s been more than a month — but my radio silence is not because of any personal tragedy or illness, it’s just that I’ve had various other things going on and life hasn’t settled back into a rhythm yet!

The main change has been that I have a new job. The particular project I was working on at the University Computer Lab had come to a close, and I thought it might be good for me to have a change after six years as a Research Associate on various projects. I’m fortunate that Telemarq is not short of work, and so there wasn’t any immediate need for me to find another post, and I could just have done that full-time: there are definitely challenges when you have two half-time jobs and have to switch mental context every other day. But I do also find it valuable to put myself into new situations to make sure I keep learning from new challenges.

So for the last couple of weeks, I’ve been in a new post as the part-time, interim, Head of Engineering at the Digital Catapult.

The ‘part-time’ and ‘interim’ bits are because I decided I didn’t want to do a long-term London commute, and certainly not a full-time one. (I’ve been spoiled by living within walking or cycling distance of my work for most of the past thirty years.) But I offered to help out while they found somebody who wanted a permanent role, and, after a long search, they did finally find somebody good, so I had the slightly bizarre experience, on my first official day of work, of being told that they had just appointed my successor! He’ll be starting soon and we’ll overlap for a bit.

So what is this strangely-named Digital Catapult?

Well, a full explanation would be too long a story and you can read more about it here, but, briefly, it’s one way for the UK’s public funding bodies to allocate resources with the aim of boosting the UK economy, alongside such things as innovation grants for industry, and academic funding. There are several ‘Catapults’ with different foci – Transport, Future Cities, High-value Manufacturing etc. – and the Digital Catapult’s aim is to provide training, facilities, advice, consultancy, and so forth, to UK institutions to help them adopt the latest digital technologies. It employs around 120 people in the process, experts drawn from many different backgrounds and areas of expertise. I like working in unusual jobs and for unusual organisations, and I think this fits the bill!

The commuting is also an interesting exploration of how others live. I’m fortunate in not always having to take the peak-period trains, but it still astonishes me that so many people around here pay nearly £50 a day — about £10K a year — to travel to and from a crowded and polluted city, spending a couple of hours per day in a stuffy compartment, and regularly don’t even get a seat; today I sat on the floor in both directions. Perhaps you get inured to it after a while. In the meantime, the seat deprivation has happened often enough already that I’ve just ordered one of these to carry with me.

Don’t get me wrong, there are compensations: the people are mostly smart and interesting, the view from the office is great, and there are plenty of good cafes and lunch spots within an easy walk to ensure that this will have a detrimental effect on my waistline. And I’m learning a lot, which was, of course, the intention. So who knows, I may be there for a bit longer than originally intended if they find a suitable use for me.

In the meantime, that explains why, for the next few months at least, I can be found in the vicinity of the British Library on Mondays, Wednesdays and Thursdays. And why I haven’t been keeping up with the blog posts, though if I manage to find trains with seats, and even tables, I may manage one or two more…

© Copyright Quentin Stafford-Fraser