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Things 127: Partner Parity Problem, Games and Stories, Beautiful Pictures

Mild NSFW warning: the last part of this edition embeds some pictures of female comic characters. There’s also a cat video, but I just assume everyone is fine with that.

Make-your-own hyperlapse video
Well, this is incredible: set a start and end point in Google street view, a target for the camera, and get as output a time-lapse video of that journey, in which you can still control the direction of the gaze – Google Street View Hyperlapse.

Here’s the demo reel.

Rabbit Hole: No to No UI
Timo Arnall says No to No UI (more commonly referred to as “invisible design”), and puts forth a detailed and cogent argument, but the main reason I recommend reading it is the warren of rabbit-hole links he uses as implicit citations. For example, Kevin Slavin talks about algorithms, how they don’t share our goals and can have emergent properties we can’t understand like a flash crash due to algorithmic stock trading, and then he takes a hop from “60% of Netflix viewing comes from the recommendation algorithm” (not true if you check carefully), a skip to “Epagogix can algorithmically evaluate the box office potential of a scipt” (no) to jump to this wonderfully flippant quote:

What does a flash crash look like in hollywood? Maybe it’s already happened! How would we know?!

Puzzle and Tim Link

Reporting on a reasonably conducted study’s findings on heterosexual parternships, the Telegraph ran with the headline “Average man has 9 sexual partners in lifetime, women have 4.”

First, what’s wrong with this claim?

Second, how does such a result come about?

Third, as the second is too easy for Things readers, I invite you to guess: which sub-set of respondents is most responsible for the discrepancy?

As some of you will know, I work at a web analytics consultancy where we disentangle data conundrums not dissimilar to this, so I wrote up my findings in a blog post – I found the answer to the last question quite satisfying!

Animal Videos – flocking starlings, evil cat
Kottke has the perfect pair of Starling flock videos – the standard high definition, clean and beautiful static camera one, and then a low resolution one that’s much more thrilling. You should watch both on as big a screen as you can.

Meanwhile, in the sub-genre of YouTube videos enlivened by a dramatic movie score, I declare this cat video the winner:

Games and stories
There is a tension between making a fun game and telling a good story; it seems to be very hard to do both at the same time. I think this might be because these represent two opposite learning methods; learning from someone else’s example, and learning by trying stuff out yourself in a safe environment.

But there’s a flip side of this conflict: sometimes, in the course of playing a game, you generate your own story, one you would never normally get to tell. Here’s an example.

I once played a match of 4-player local GoldenEye, back when I wouldn’t have needed to specify that 4-player GoldenEye was local. I ran out of ammo, and was chased down a twisty dead end by my friend who had some kind of machine gun, so I was pretty much doomed. I did have one thing though, and I said as much:

“I’ve got a proximity mine. If you come any closer I’ll kill us both!”

He laughed, and continued to pursue me round the final tight corner.

I set the proximity mine.

It killed us both.

I don’t remember the final score of that game – I don’t think I did well. But that tiny story remains one of my favourite gaming moments. For that reason, I was very interested to read Tom Armitage’s review of Game Dev Story, a cute little game that crudely simulates running a game development studio through the major console generations, because he made this assessment:

Game Dev Story exemplifies a kind of mechanical storytelling: stories told not through text or voice-acting, but through coherent systems that cannot help but generate stories.

I gave it a go, and he was absolutely right. Apart from the sense of ownership you get from making company decisions, the ability to name your company and the games you produce has some kind of magical effect that makes the whole thing strangely compelling.

It’s not a great story, but it meant a lot to me: after a difficult start, Squidopolis released a string of titles whose success built a war chest which specially trained hardware engineer Stephen Jobson put to use in developing the ultimate console: the Kraken, for which we then produced a string of hits, despite some major setbacks in production.

Game Dev Story is available on Android and iOS.

Folk Games
I like the term ‘folk games’ for equipmentless games a group of people can spontaneously play, such as Standoff, or Ninja, or Fantasy Fencing. I highly recommend all of those, the last one being particularly notable as it is an example of the ‘Tiny Games’ that Hide & Seek are putting into an app (so you don’t have to memorise these sort of things for every occasion). That’s happening on Kickstarter, and with a day to go at the time of writing it’s already funded, but I still recommend the £12 tier (which includes their Board Game Remix kit) to help reach the stretch goals!

Tim Link: Devil May Dance
I like putting in place processes in which incremental progress is made towards a goal, and this year I reached the end of my biggest project so far: I finished my webcomic, Devil May Dance, which I had been updating weekly since April 2006.

The premise was to swap the macho protagonist of the video game Devil May Cry with the feminine lead of seminal rhythm action game Space Channel 5, and see how they got on in one another’s shoes, partly as a way to investigate gender expectations, and partly as an attempt to get some cheap laughs.

If that sounds interesting to you, or if you’re curious what would happen if I wrote a story involving time travel, you should check it out.

I also did a little summary of the web stats of the comic over its lifetime.

Beautiful pictures.
Sunset on mars. Pictures with High Dynamic Range. Icebergs that are naturally stripey. An abandoned epic communist building.

But more importantly, there’s another Kickstarter I’d like to draw your attention to. A friend of mine illustrates comics using primarily traditional techniques, and although she works incredibly hard, I get the impression this means she can’t turn out pages at the kind of speed a regular publisher would like (on account of having to wait for individual colours to dry!), so this is exactly the kind of thing Kickstarter is good for – delivering the kind of projects the invisible hand would usually hold back.

Unfortunately, according to kicktraq’s projection, at a little over half way through, the project has a 50/50 chance of success, so it’s going to need some extra help to make it. Check it out before April 24th!

-Transmission finally ends

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Things 121: Kitten Cam, Chain World, Hand-Waving Explanations

Tim Game Thing
If you ever watched Knightmare and wanted to be the kid in the vision-restricting helmet asking “Where Am I?”, or if you wanted to be the team responding “You’re In A Room” and then frantically shouting “Sidestep left”, or perhaps if you wanted to come up with your own ideas for dungeons for those players to explore, then I recommend you come along to Hide & Seek’s free Sandpit event this Friday 25th May (6.30pm-10pm at the Royal Festival Hall near Waterloo), where I’ll be running a game that gives you an opportunity to do exactly those things.

There will also be a lot of other games going on, which sound pretty amazing, so read all about it, and come along.

VideoCat and Kitten webcams
Which is more compelling: a high resolution webcam of some kittens, or low-resolution webcams you can move around and remotely operate cat toys through (if you’re prepared to use Internet Explorer and Silverlight)?

It turns out that even though the latter sounds superficially cooler and more engaging, it’s nowhere near as good as high-resolution kittens.

LinkJason Rohrer’s Chain World
Jason Rohrer has made some very interesting games (I particularly like Sleep Is Death (or at least the idea of it – I haven’t played it yet), Inside a Star-filled Sky, and Passage is apparently pretty amazing (and very short) if you don’t play it stupidly the first time like I did), so it’s not particularly surprising that he came up with the winning concept in a competition to pitch an idea for a game that in some way represented the abstract idea of religion, and which, when actually released into the world, generated some pretty fascinating results.

Heavily Caveated Film Recommendation
The Green Hornet is a Seth Rogen action/comedy vehicle directed by Michel Gondry. If you analyse that sentence you may realise that this was recipe for disaster. With Seth Rogen starring and also writing (with long-time friend and collaborator Evan Goldberg), there was inevitably going to be some creative conflict with a director as idiosyncratic and driven as Michel Gondry (the man behind some of my favourite music videos).

Trailer: (2’06” is the moment that screams “Gondry!”)

Refreshingly, listening to the commentary makes this very clear, as Gondry, Goldberg and Rogen frequently reference the arguments behind almost every good idea in the movie, and occasionally break into new arguments about them (“We had to convince you that this would work!” “No no no! This was my idea! You guys didn’t want to let me do it!”).

This conflict doesn’t particularly damage the movie, but I ended up wishing Gondry had had more things go his way, because all the really weirdly brilliant parts are unmistakeably his. For example, at one point, the bad guy wants to send a message out through his criminal network, and this is how Gondry represents it:

http://www.youtube.com/watch?v=UA5ZuJdrgyc

It’s also great to hear his enthusiasm for his own ideas in the commentary, as when this scene starts: “This is awesome, look! Two cameras from one camera! How… did… the hell it happen?!” (Answer: they got the actors to stay in position while shooting one part, then came back to them and picked up shooting from the same position, then forced the shot to match in digital post-production, which is fine, but just count the splits and think about actually pulling that off).

The real problems with this film (to save you the trouble, it’s a 6.0 on IMDb and 44% on Rotten Tomatoes) are I think twofold:

1) Goldberg and Rogen consciously chose to reverse many of the staples (some would say clichés) of a superhero movie, which is admirable, but as is so often said, you need to be very familiar with the “rules” of any art form if you want to break them and still have the thing work, so this sentence ends in just the way you would expect.

2) There’s a fine art to crafting an action movie in which the audience can root for the protagonists, even when they’re harming or even killing bad guys. I don’t know how you pull this off, and apparently neither did anyone making The Green Hornet, because these moments frequently feel wrong.

All of which was fascinating, and I don’t regret watching the movie at all.

Answer 2A and 2B – Temperature/Pressure Pairs
Do there exist a pair of points opposite one another on the earth with exactly the same temperature and pressure? I say yes, and here’s my hand-waving explanation for that.

Stage 1
Let T(x) and P(x) denote the temperature and pressure of point x.

Choose two opposite points, A and B (if T(A) = T(B), do this stage with pressure instead of temperature). Consider a path from A to B (blue arrow in Fig 1a) and the corresponding opposite path from B to A (red arrow in Fig 1a).

In Fig 1b, we chart the temperature of the opposite points as we move around these paths. Just as with the Joss Whedon ascent/descent puzzle, since each line of temperature is continuous, they must cross at least once, and this represents a point at which the temperature is equal on opposite sides of the globe (points C and D in Fig 1b).

Stage 2
We now imagine rotating the circlular path we’ve considered about points A and B (Fig 2a). As we do this, the lines of temperature move continuously (Fig 2b), but since they always start and end at points A and B, the end temperatures remain fixed, and so the point at which the lines cross also moves continuously.

This starts to trace out a line of equal-temperature-opposite-points on the globe (turquoise and purple lines in Fig 2a).

Stage 3
If we continue that rotation all the way around, we trace out a continuous wiggly line of equal-temperature-opposite-points around the globe (Fig 3a, purple and turquoise lines).

We now consider two opposite points on this line, C and D (Fig 3a). We consider the pressure as we trace out a path from C to D (purple line) and the corresponding opposite points on the path from D to C (turquoise line). We can now apply exactly the same argument as in Stage 1 – the two lines of pressure (Fig 3b) are continuous and so must cross at some point, X. At that point, both the temperature and pressure are equal on opposite sides of the globe.

While this is not a proof, it’s reassuring that the Borsuk-Ulam theorem does prove that the result is true, although that’s no garantee that this reasoning is completely sound.

Dom Camus supplied a similarly hand-waving explanation but with a much more audacious line of attack, so if you liked the above, you should definitely check it out.

Phil has a pretty elegant approach, although he didn’t sound that convinced by it. He points out that “On any closed curve (not just great circles), the same sort of argument [as in Fig 1 above] holds […] I claim you can always construct a closed curve containing all its own opposite points and along which the temperature is everywhere equal at opposite points [like the turquoise/purple path in Fig 3]. Otherwise there would be some closed curve containing all its own opposite points, along which the temperature was never equal at opposite points, a contradiction.” You can then repeat Step 3, as above, to reach the same conclusion.

Puzzle Level 3The Crumpled Map
The final level in this series (suggested to me by Tarim) is one I don’t have any kind of hand-waving proof of, but I would love to see one.

Imagine you are on a lovely desert island with a selection of your favourite music, a pencil and paper, and an uncannily perfect map of the island. Actually, only the map is important.

If you lay the map on the ground and align it perfectly with the island itself, it’s quite easy to visualise that there must be a single point on that map which corresponds precisely to the bit of the island directly below it.

Now imagine folding and crumpling the map in any kind of way (but not tearing it) and throwing it anywhere on the ground. Wherever it happens to land, will there still be a point on the map that exactly corresponds to the place on the island directly below it?

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Things 112: Eyes, Guessing Cat, Amigara Fault

This week Things has a very slight Hallowe’en theme.

Puzzle
This is one where you should gather some people around the monitor and see who can do best: guess the cartoon (or CG) character from their eyes (mouse over the eyes to see the character outline that should tell you if you’re right).

And yes, it is pretty difficult – I only got 6, and I watch a lot of animation!

Video
Here’s a video that begs the question: is the cat playing the game, or just acting out of blind instinct?

http://www.youtube.com/watch?v=QrlTijuhVOA

To which the answer is to have a big argument about the definitions being used before concluding that you can’t tell.

Quote
In the wonderfully stylised animation The Secret of Kells, I heard the line “One beetle recognises another” and wondered if it was some kind of proverb. It turns out that it is, and actually – obviously – there are a whole bunch of Irish Proverbs, which in translated form become alternately profound, banal or hilarious, just as I imagine English proverbs must seem if you haven’t grown up with them. Here’s a list of them on Wikiquote, and here are a few of my favourites, for unstated reasons:

“Every beginning is weak.”

“Time is a good story teller.”

“A lamb becomes a sheep with distance…”

“The quiet are guilty”

Comic
The Enigma of Amigara Fault is a horror comic that impressed me with its unconventional approach. It’s 32 pages, and originally in Japanese so you have to read the panels right to left. But if you want a comic that will freak you out for Hallowe’en, it’s worth it. Unless you’re particularly claustrophobic, in which case you should probably steer clear of it entirely.

Answer – Malady X
In Things 111 I asked what the probability of having Malady X is if a randomly administered 99%-accurate test for it comes back positive. As Phil and Thomas noted, you can’t actually answer from this information alone: you also have to know what the probability of a random person actually having Malady X is. A lot of people don’t have an intuition for this fact. I’m going to attempt to explain ways to apprehend that hand-wavingly, mathematically, and visually.

Argument from hand waving and examples:
Imagine the probability of having Malady X is 0% – nobody has it. In this case, it’s certain that getting a positive result means you were simply in the 1% of cases where the test comes back incorrect.
Conversely if the probability of having it is 100% – everybody has it – then you must be in the 99% of cases where it is accurate. In this way, it’s clear the underlying probability influences the chances that the test is correct!

We might worry that these extremes somehow break the puzzle, so let’s imagine less extreme alternatives. Imagine 1,000 people are tested. If 50% (500) really have Malady X, on average we expect the test to come back positive for 99% of them (495) and also for 1% of the 500 that don’t have it (5). In this situation, 495 out of the 500 people for whom the test was positive actually have the disease – 99%.

Alternatively, if 1 person (or 0.1%) out of the 1,000 has the disease, they’re very likely to be correctly diagnosed, and we expect roughly 10 of the other 999 to get a positive result. In this case 1 out of 11 people with a positive result actually have Malady X – fewer than 10%. So clearly the underlying incidence level matters.

Argument from maths:
There are two probabilities at work: the chance the test is correct (99%) and the chance of anyone having Malady X (unknown – let’s call it X%). When you combine probabilities you multiply them, so for example the chance of anyone actually having Malady X AND getting a postive result is 99% times X%.

If someone gets a positive result and that’s all we know, we reason as follows:
A = Probability someone has Malady X and tests positive = X% times 99% times
B = Probability someone does not have Malady X but still tests positive = (100% – X%) times 1%
If you test positive, the chance you actually have it is C = A / (A+B). But if you haven’t studied probability carefully, I’m not sure you could infer this, which is why I like to come up with other ways of getting a feel for the correct answer.

Argument from visualisation:
Since there are two probabilities in question, and we combine probabilities by multiplying, this naturally suggests a visualisation where probability is represented by rectangular area (since area is calculated by multiplying height by breadth).

For example, if we imagine the actual incidence rate of Malady X is 50%, the picture would look like this (click for big):

If the test result is positive, you either have it and the result is correct (big yellow area) or you don’t have it but the test was incorrect (small dark blue area). The chance of you actually having Malady X is equal to the proportion of those combined areas that is yellow. In this case:
Yellow = 99% x 50% = 49.5%
Dark blue = 1% * 50% = 0.5%
Probability you have it = Proportion that is yellow = 49.5% / (49.5% + 0.5%) = 99%.

Alternatively if the incidence rate is, say, 2%, it looks like this:

Here we see the yellow and dark blue areas are very similar, so the chance of you being one or the other is much more even. In fact, it’s:
Yellow = 99% x 2% = 1.98%
Dark blue = 1% x 98% = 0.98%
Probability you have it = Proportion that is yellow = 1.98% / (1.98% + 0.98%) = 67% (ish).

As Peter Donnelly shows in this TED talk, this actually has some severe ramifications, because when the probability of the thing being tested for is extremely low, it becomes overwhelmingly likely that a positive result is false, but people intuitively feel that a 99% accurate test should be correct 99% of the time.

Thomas also noted:

If anyone is interested in playing around with the probabilities (even if you’re not familiar with the maths), I recommend GeNIe:
http://genie.sis.pitt.edu/
It lets you create networks of dependencies, set evidence and work out probabilities in problems just like these.

-Transmission finally ends

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Things 111: Malady X, Stretching Cat, 3 Panels

Question
(Thanks to Simon for reminding me of this important probability lesson!)

At random, you are tested for Malady X. Alarmingly (particularly given that you don’t even know what Malady X is) the test comes back positive. But you know these tests are not always perfect – there’s a chance that it’s wrong, and you don’t really have Malady X at all. So you ask how accurate the test is. You are told that if someone really does have Malady X, there’s a 99% chance the test will come back positive; for someone that doesn’t have it, there is a 99% chance the test will come back negative.

What is the probability that you actually have Malady X?

Animated Gif
Here is the best animated gif of a cat I have seen in a long time:

Link
(via Silv3r): A huge and (I think?) growing collection of street fliers that play with the form, some okay and others quite, quite brilliant, can be found here (browse the other pages if you like what you see).

Picture
I am proud to be able to say that I know James White, the author of this perfect 3-panel comic, personally.

Answer
Last time I asked about what people really mean when they claim “change is accelerating”.

The most direct and plausible answer came from John B, who suggested that the scope of human knowledge is the thing that is really growing, and the subjective change we experience is what arises from these discoveries. While it’s only a proxy, one way to measure this is to track how many patents are granted over time, and on a logarithmic scale this does look kind of linear (indicating acceleration).

Bex has an alternative view. The perception of change seems to generally accelerate with age (which in itself is already enough to explain why people claim this all the time). The population of the UK (at least) is ageing. Therefore, the speed-of-change will be reported to be, on average, faster over time. Sneaky!

As the Wikipedia article on the subject currently notes, another confounding factor could be the growth of the human race itself. For example, if a fixed proportion of humans files patents, exponential growth in human race will directly lead to exponential growth in patents filed.

In any field, taking any trend and extrapolating it arbitrarily far into the future is generally unwise. If we don’t know exactly what we’re measuring, and we don’t understand the factors governing the change, even less so. Given the potential disruptions of the technology we’re seeing already, if anything it seems just as likely to me that sudden power imbalances become more likely, which could lead to large swathes of humanity being wiped out, or global human society turning into a dead-end all-powerful dictatorship with no desire to change the status quo.