Tag Archives: experiment

Things 109: Jonathan’s Card, Dr Who Cats, Mix Shift Visualisation

Question – Nothing to Hide
As technology makes surveillance of many kinds ever easier, some people  are worried about Big Brother, two words which conveniently encompass the general idea that this would be bad, via Orwell’s 1984, which incidentally is one of those classics that you really should read if you haven’t yet as it is only becoming more relevant.

In response to this, others say “If you have nothing to hide, then you have nothing to fear,” which is powerfully concise rebuttal to these vague fears.

I can think of some counterarguments to that, but they tend to be long, and as noted by The Brads, something that takes more than 140 characters to explain doesn’t generally spread. So: this week’s challenge is to come up with a counterargument for “nothing to hide” that is 140 characters long or fewer.

Link
A while ago, as an experiment, Jonathan Stark made his Starbucks card details public, so anyone could add credit and anyone could spend that credit. His page explaining this is here. (Note the caveat at the top – this no longer works).

Sam Odio found an easy way to transfer credit to his own Starbucks card, and I recommend reading his take on the idea (and his exploit) here.

If you don’t have time for that, you could just read this summary of the whole story over at Good, which lays out the whole strange tale.

Quote
Les Dawson:

“There is a remote tribe that worships the number zero. Is nothing sacred?”

Picture (via Jason)
Pure internet linkbait, but with an execution this good, it deserves to be: Dr Who cats.

Previous Puzzle
Last time I asked for ways to visualise data in such a way that mix shifts affecting conversion rate would be readily apparent.

Adam naturally had a full consultant’s answer, explaining how he would show the data different ways depending on the audience (sales director, website content manager, SEO manager…), and how he might talk through the component parts of the change in a sequence of slides, which is all very sensible. However, what I really want is something that I as an analyst can look at to apprehend the whole situation, ideally in a generic way, so any given shift becomes clear.

Simon described an interesting single-view answer, but in preparing this post I realised I needed to confirm some of its details with him, so that will have to wait for a later edition of Things.

On to my answer… the data set was as follows:

[before mix shift | after mix shift]:

Banjo section visits [10,000 | 20,000] – lots more traffic
Banjo section sales [100 | 220]
Banjo section conversion [1.0% | 1.1%] – conversion increases!

Gun section visits [1,000 | 1,000] – same traffic as ever
Gun section sales [100 | 110]
Gun section conversion [10% | 11%] – conversion increases!

Overall conversion before:
(100 + 100) / (10,000 + 1,000) = 1.82%
Overall conversion after:
(220 + 110) / (20,000 + 1,000) = 1.57% – overall conversion has decreased!

My solution looks like this:

This shows how the total visits and orders (black lines) are composed of the individual sections (red/gun and blue/banjo). While both the blue and red arrows get steeper (representing improved conversion, although it’s hard to see this on the red arrow), the angle of the black line decreases (representing the overall decrease in conversion), since the blue arrow became so much longer.

This pretty much works for the extreme example given. However, it has significant weaknesses as a general solution:

  • It doesn’t work as a trended view – conceivably it could be animated, but that seems like overkill
  • It’s hard to compare the angle of arrows when traffic changes significantly, as in the gun section above
  • It tends to encode all the interesting information into a narrow diagonal band of the chart.

Further improvements are of course welcome!

-Transmission Ends

Things 44: Celebrations Results, Cat vs Squirrel, Procrastination Flowchart

(Originally sent April 2009)

Movies
This week I chose to see a film with Nicolas Cage in it instead of Slumdog Millionaire at the cinema, and I did not regret it. Insane big-budget B-movies like Knowing are the best thing to see on a big screen.

My review:

httpv://www.youtube.com/watch?v=uevBawlFZ1g

Blog
A rare event – I updated my blog, with the results from my Celebrations experiment.

Link
A reference for April Fool’s websites in 2009.

Quote
As referenced by my flatmate in the review of Knowing – Donald Rumsfeld, 2003, making a good point badly:

“Reports that say that something hasn’t happened are always interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t know we don’t know.”

Followed up by:

“I believe what I said yesterday. I don’t know what I said, but I know what I think… and I assume it’s what I said.”

Last Week’s Puzzle
Last week I asked about the 3rd most abundant element in the universe – it turns out to be Oxygen.

Puzzle
This week: a puzzle I don’t think I am quite able to set with sufficient precision, but will try anyway. You can buy some things in packets/tins/boxes and they list the number of items they contain, such as 6 eggs, 12 spoons, 52 playing cards. With a budget of £5, what would you buy to get the largest possible value for this number?

Video
Squirrel vs cat:

httpv://www.youtube.com/watch?v=RNhbTmKqQOE

Picture
A procrastination flow chart (click for big):

Things 96: Rocket Path-Dependency, Lipstick Animals, 3D Doesn’t Work

Link
When speculating on the subject of extraterrestrial space-faring life, it’s all too easy to forget the many development factors that are likely to be local to us, and to assume that too much of what we have done will generalise to other life forms out there. This article puts forward a compelling argument that our rocket-based space-faring only arose because of certain very specific and not particularly likely events.

Quote
While I don’t think it could be objectively assessed, I rather like Arthur Koestler’s observation on originality:

The more original a discovery, the more obvious it seems afterwards.

Picture
This is one of the things that makes me think of that Arthur Koestler quote: lipstick animals.

Lots more here.

Question
Why 3D doesn’t work and never will. Case closed.”
Roger Ebert quotes Walter Merch, as a Man Who Knows What He’s Talking About, who presents several arguments as to why 3D cinema can never work.

I’ve heard a lot of bad arguments on both sides of this debate, so it’s nice to see someone with a deep understanding of the medium draw out their arguments clearly. My question is, is he right?

Previous Puzzle
Last time I asked how a mouse could fall any distance and survive.

As Phil pointed out, the statement is strictly false: “a mouse certainly can’t fall further than the size of the universe, for example.” So instead we restrict ourselves to consider mice falling off things that are attached to the earth, and no higher than the point at which the atmosphere becomes too thin for a mouse to breathe, and that the survivability criterion is assessed upon landing, and that the landing area itself is not deadly to mice.

First we must address the idea some people recall from school that all objects fall at the same speed, as per Galileo’s thought experiment and his apocryphal dropping-objects-from-the-tower-of-Pisa experiment. This is clearly false as a feather falls more slowly than a hammer, and the confounding factor is air resistance. Rather excellently, the hammer-feather experiment was conducted on the moon to show that in the absence of significant air resistance, they will actually fall at the same speed:

httpv://www.youtube.com/watch?v=PE81zGhnb0w

When air resistance is introduced the shape and particularly the downward-facing area dimensions of the falling objects matter, and although it’s hard to have a good intuitive feel for this when comparing such random objects as animals, I find it’s much easier to imagine a kind-of equivalent parachute with a weight attached.

A small parachute with a big bag of hammers attached will be pulled down more quickly than the same parachute with a feather attached. Alternatively, if two parachutes have equal weights attached, but one parachute is much bigger than the other, it’s easy to imagine that the bigger parachute has greater air resistance and so will fall slower.

Now if we imagine a parachute the size of a mouse, with a weight attached that is the same weight as a mouse, we can imagine it will fall pretty slowly, particularly compared to a parachute the size of an elephant with a weight attached the same weight as an elephant. So we can intuitively understand that the mouse survives.

Or perhaps we can’t? I realise that wasn’t very scientific, but I tend to prefer thought experiments of this kind as they seem to help most people grok ideas better than formulae.

This article over at Everything2 also has some concise words to say on the subject of falling animals.

Things Christmas Special 2008

(Originally sent… okay, you can probably guess)

It’s Christmas and Things has been running for over a year. I’m taking that as an excuse to break with the usual format, and also to highlight what I (and some others) consider to be the best of the year’s Things.

Urgent matters first
I bought 10 tubs of Celebrations chocolates, discovered the average distribution of the different types, then created tubs of each kind and put them on eBay for charity to determine their value. I wrote up the initial results in my new blog:

http://toweroftheoctopus.com/2008/12/the-celebrations-experiment/

The auctions end AT LUNCHTIME TODAY!

Check out how they are doing, or bid if you are so inclined, here:

http://www.tinyurl.com/TimEbay

[It’s long over now, read the final results here – T.M. 22/1/11]

Videos
Here are some videos that I like.

1) Tim ‘Speed’ Levitch is an extraordinary fellow that speaks in paragraphs that would take most other people hours to come up with. In the following video he holds forth on the New York grid plan and builds to a brilliant conclusion.

To sell you his style just a bit more, here’s his spontaneous introduction to a comment on a homeless person he passes while walking down the street: “[that person], under the white comforter, cuddled up with 34th street and Broadway, existing on the concrete of this city, hungry and dishevelled, struggling to crawl their way onto this island, with all of their machinated rages and hellishness and self-orchestrated purgatories…”

httpv://www.youtube.com/watch?v=9awJCyjt550

2) Somebody put a few frames of an anime featuring a woman spinning a leek around to a brilliantly loopy sample from an obscure band. A massive internet meme was born. Here’s where it all started (reposted).

Wikipedia article on the phenomenon.

3) This is my favourite tune and music video right now, and the intro guy is awesome too:

httpv://www.youtube.com/watch?v=wGDlCViI6k8

Pictures
This guy makes armour for cats and mice. Or perhaps more accurately, scale sculptures that resemble such things:

Best of Things 2008

Link:
Worst translated menu in the world

Quote
XKCD on dreams and possibilities.

Video
Acoustic Resonance – rice is used to illustrate standing acoustic waves on what I presume is a metal plate:

httpv://www.youtube.com/watch?v=Zkox6niJ1Wc

Picture
Analemma (click for big):

If you don’t know what an Analemma is, try to work it out from the photo.

Puzzle
The rainbow paradox, remains one of my favourite and (as far as I am concerned) unresolved puzzles:

Soundwaves can vary in frequency across a vast range, part of which we can hear. The lowest part we perceive as a deep bass, the highest as a high squeak.

Similarly, the electromagnetic spectrum consists of a vast range of frequencies, a small range of which we are able to see. The lowest frequency we can see is what we call red, and the highest frequency is what we call violet.

However, while we perceive the ends of the audible sound spectrum to be very different, the ends of the visible light spectrum, red and violet, seem very close to one another, and we even have a colour we call purple that is a mix of the two yet does not actually appear anywhere in the spectrum between them. In fact, we can draw a circle of the colours we perceive and it is not at all clear where the ‘ends’ are.

Why is this?

That’s it for Things until 2009.

Happy Thingking!

Tim