larkery

Conjecture about K-complexity

Thu, 02 Feb 2012 14:31:00 +0000

Conjecture: for any finite set of bit strings S and a chosen ordering of S, it is possible to define (or there exists) a machine M where sorting S by the Kolmogorov complexity of its members with respect to M constructs the chosen ordering.

Answers on a postcard.

"He has an honorary position as official Shoutsperson of the University of York’s Douglas Adams..."

Mon, 12 Dec 2011 22:10:07 +0000

“He has an honorary position as official Shoutsperson of the University of York’s Douglas Adams Society,[14] and in 2011 the University’s student body voted to name a new study space as the ‘Brian Blessed Centre for Quiet Study’.[15]”

- Brian Blessed - Wikipedia, the free encyclopedia

(Untitled)

Sat, 12 Nov 2011 12:51:18 +0000

(Untitled)

The Social Graph is Neither

Thu, 10 Nov 2011 12:14:21 +0000

The Social Graph is Neither:

Lazyweb writes the article that explains what I think yet again.

(Untitled)

Mon, 07 Nov 2011 04:04:44 +0000

(Untitled)

Monochrome cupboard cat

Wed, 02 Nov 2011 10:06:53 +0000

Monochrome cupboard cat

The Mensch Hypothesis

Mon, 31 Oct 2011 10:17:00 +0000

You may have seen Louise Mensch being needled on HIGNFY recently; if you haven’t, take a look, it’s awful and funny at once.

Mensch suggests that there’s something wrong about the Occupy LSX protestors drinking coffee from the nearby Starbucks, something which renders their position invalid. Merton & Hislop both mock this view, and get some good laughs in the process; fair enough for a comedy show but this is the internet where such things are SRS BZNS. Let’s look at what Mrs Mensch says a bit more closely, as it’s a common refrain - “look at those guardianistas, smashing their system on their iPhones”, hilarity and dismissal ensue.

The argument here is one of hypocrisy, that lattes etc. are fruits of the economic system, and their consumption implies and depends upon supporting it. The protestors should be ignored because they are hypocrites (the cardinal modern sin), saying one thing and acting in contradiction. Let’s consider what is needed for this critique to hold up:

The protestors believe they ought to be able to have a coffee
The protestors take issue with the skewed wealth distribution and other current inequalities.
(MH) Said wealth distribution is necessarily implied by the availability of a coffee.
Thus, the protestors’ actions (1) contradict their complaints (2) - they are not walking the walk.

From this we have the Mensch Hypothesis of capitalism: there can be no economy in which a coffee may be bought for a low price in which executive remuneration does not double every couple of years. No lattes may be had without the top 1% holding a radically disproportionate fraction of the wealth (and thus power). To shave even a single pound from the pension of Fred Goodwin or the salary of Bob Diamond would octuple the price of espresso, in all possible worlds.

cat helping with work

Mon, 22 Nov 2010 10:17:00 +0000

[Flash 10 is required to watch video.]

cat helping with work

Time Tree: phylogenetic common-ancestor lookup

Sat, 11 Sep 2010 11:52:49 +0100

Time Tree: phylogenetic common-ancestor lookup

The Acceleration of Addictiveness

Tue, 03 Aug 2010 16:32:22 +0100

The Acceleration of Addictiveness:

An interesting note by Paul Graham

(via dihard, via jakelodwick via Ronen Reblogs)

Ergonomics

Tue, 13 Jul 2010 15:30:26 +0100

Been typing a lot recently and I have just noticed something blindingly obvious: the num pad is on the wrong side of the keyboard for right handers. Either the mouse ends up off to the right, or your left arm has to be in the wrong place. Why is this considered a good idea?

Conway's Free Will Theorem

Fri, 21 May 2010 12:12:00 +0100

Conway's Free Will Theorem

Electoral Reform

Fri, 07 May 2010 18:14:00 +0100

We need to reform the electoral system in the UK; I know it’s a topic which sounds utterly dry and tedious, but the lack of fair representation is at the heart of many of the problems in our politics at the moment. If you are already convinced of the need for reform, please take a moment to sign this petition at 38degrees. If not, read on for an explanation of the faults in the system and possible solutions.

What’s wrong with what we have?

Parliamentary elections in the UK are currently decided using First Past the Post (FPTP). In a FPTP election, some candidates stand in each constituency and are listed on each ballot paper. You, the voter, express your preference by making a mark next to a candidate. In each constituency, the winner is the candidate with the most marks, who then goes on to represent you and your fellow constituents in Parliament. A completed ballot paper looks something like this, with the vote marked by X :

Joe Bloggs (Lab)
Jan Smith (Con)
Phil Jones (Lib)
Emma Thomas (Plaid) X
Adolf Hitler (BNP)

Here I have voted for Emma Thomas, because of my strong Welsh Nationalism. Anyway, although this seems like a fair way of choosing a candidate, it is fraught with problems, in particular the need for tactical voting and giving power to the media and selection committees. It also fails to represent minority interests at a national scale. It does however provide the important benefit of the so-called constituency link, as every voter has an MP who is supposed to represent their local interests in Parliament. Now let’s look at some of these problems in more detail.

Tactical Voting

Tactical voting is the practice of voting for a candidate other than the candidate you would ideally like to win; to see why this can be necessary, consider the example above. Say the hypothetical constituency described has a hard core of BNP voters, who make up 21% of the voting population, but has equally shared support for the other four candidates. If the 79% of non-BNP voters all feel that they would rather have any other candidate than Adolf, but they all vote for their first choice, each non-BNP candidate will receive 19.75% of the vote, and Adolf will win with 21%. This is a bad outcome because what has happened is what the overwhelming majority of the voters least wanted to happen.

To achieve a desirable outcome, every non-BNP voter needs to somehow agree on which of the other 4 candidates they will select; consequently the correct vote for each individual depends on how they believe every other individual will vote (and vice-versa). This need to guess others’ votes is what causes the other negatives of FPTP. Firstly, it gives a lot of power to the media and opinion polls, because the media’s representation of how the popular vote will go affects everyone’s tactical voting choices. Secondly, FPTP gives power to the parties, as they can field unpopular candidates against even less popular opponents; every voter in a constituency can be faced with the dilemma of voting for a good representative from a party they dislike or for a non-local poor representative parachuted in by a party whose manifesto they prefer. Because fielding two candidates in the same constituency would split the vote, no party will ever offer voters that choice, and we are stuck with the lesser of two evils.

Finally it’s worth noting that FPTP regularly elects candidates with minority support in their constituency, and that most people who go to the polls might just as well have stayed in bed! It is in this sense that most votes are wasted.

All of these problems stem from the fact that FPTP doesn’t recognise that most voters have a ranking of the candidates, from most favoured to least favoured, instead of just a single favourite. One way to accommodate voters’ true preference is Preference Voting.

Preference Voting

Joe Bloggs (Lab)
Jan Smith (Con) 2
Phil Jones (Lib) 3
Emma Thomas (Plaid) 1
Adolf Hitler (BNP)

Here I have placed Emma Thomas first, Jan Smith second and Phil Jones third in my ranking. To decide an election we count up everyone’s first choice vote (this part is just like an FPTP election). Now, if any candidate has sufficiently many votes (more than half, for example), they are the winner. If there is no clear winner, the candidate with the fewest votes is eliminated and their votes are re-allocated according to their supporters’ next choice; this process repeats until there is a clear winner.

Preference voting ensures that any candidate selected is acceptable to a majority of the constituents, given their fellow constituents’ decisions, and takes power from the media and party selection committees by making voting intentions irrelevant (you no longer need to guess how your neighbours will vote to vote effectively; the process effectively tactically votes on your behalf) and allowing multiple candidates from the same party to stand in one constituency without splitting that party’s vote.

This superior voting scheme (variously called Instant Runoff Voting, the Alternative Vote and Preference Voting) can only serve to strengthen the constituency link and restore fairness to the system by ensuring that every MP has the broadest possible support of their constituents and making every vote count.

Non-Proportional Representation

A voting system is proportionally representative if the makeup of the Parliament accurately reflects the number of votes across the country, so if a party receives 10% of the vote nationally they also have 10% of the seats in Parliament. FPTP is obviously not proportional, since if a party receives 51% of the vote in each constituency they have 100% of the seats nationally. In fact, under FPTP the party with the fewest votes overall can have the most seats, and the party with the most votes the fewest seats! Unfortunately truly proportional representation cannot be had without losing the constituency link, since you can’t have 5% of your local MP be from the Labour party and 10% from the Conservatives, and so on, and there is a real discussion to be had about whether we value localism above proportionality in our system. True proportionality also allows extreme fringe political groups into the Parliament, which some people believe is a bad thing.

Single Transferable Vote

The single transferable vote is one approach which allows a variable trade-off between proportionality and localism, hopefully allowing for a middle ground which captures enough of both laudable features. Under STV each constituency has several MPs, say 2 or 3 (so to keep Parliament the same size some constituencies would need to be merged together), and Preference Voting is used to select them (Preference Voting can choose multiple candidates by reducing the winning post and allocating the second preferences from excess votes for a winning candidate; it’s more complicated but preserves all of the good features already mentioned). In this way the makeup of the parliament is roughly proportional, but each voter is still personally connected with the MPs they have elected. In fact, by changing the number of constituencies & MPs, STV allows us to go from plain Alternative Vote with strong local representation to a fully proportional system where the entire country is a giant constituency and everyone ranks every candidate. Somewhere between these two is a fair, British compromise.

Common Canards About Electoral Reform

It Would Break the Constituency Link

As we have seen, with STV the constituency link is preserved, and Preference Voting can only serve to strengthen it by ensuring representatives have popular support.

It Would Let the BNP Into Parliament

With a small number of seats for each constituency, STV allows some proportionality but with a bias away from really small parties. More significantly, I would argue that if a lot of people vote for the BNP they should have some representation, and if their arguments are so weak they should be allowed to fall on their own. Respect for the intelligence of other voters is a cornerstone of the universal franchise of democracy, and it is profoundly undemocratic to say that some people are so wrong their voices should never be heard. If extreme views do not wilt under the light of reason, all we can hope for in the long run is a benevolent dictatorship (perhaps a philosopher king).

It Would Lead to Coalition Governments

PR systems lead to coalition government if the population vote for coalition government; coalitions have run most European states successfully for the better part of a century, and if the alternative is minority rule we might as well abandon democracy. A coalition should simply ensure that any legislation passed is supported by representatives who between them carry the majority of the popular vote. In fact, I believe that a coalition model would improve the quality of our politics dramatically, by forcing politicians to focus on common ground instead of the childish and divisive demonising of the Other Team. The political discourse in America seems like the likely end-game for adversarial politics, and it is very ugly.

It Gives Parties Too Much Power, Through Party Lists

Under list-based PR, like Israel uses to elect the Knesset, this is true. Voters choose a party, rather than a candidate, and the party then allocates its seats to candidates as it sees fit. With STV, the power of parties to select candidates is further transferred to the voters, since voters can choose between multiple candidates of the same party. This also allows voters to better communicate their support to the parties; for example you may support Old Labour and dislike New Labour. Your vote can reflect this by ranking an Old Labour type candidate above a New Labour one.

Emacs & Dictionary.app

Mon, 22 Mar 2010 13:04:00 +0000

How to integrate Mac OS X’s Dictionary.app with Emacs

You will need: a function to send the word at point to the dictionary

(defun mac-open-dictionary (the-word)
    "Open Dictionary.app for the-word"
    (interactive "sDictionary Lookup: ")
    (shell-command (concat "open\"dict:///" (replace-regexp-in-string "\"" "\\\\\"" the-word) "\"")))

And to make it even better integrated, a binding to the normal dictionary keys (⌘-⌤-D)

(global-set-key [C-s-268632068] '(lambda () (interactive) (mac-open-dictionary (current-word))))

Odds Are, It's Wrong

Fri, 19 Mar 2010 13:24:07 +0000

Odds Are, It's Wrong:

An interesting article from “Science News” about the pitfalls of ill-informed use of statistical techniques to decide on the significance of observed correlations. The subject is very complex and fraught with difficulties, and the reduction to Frequentists vs. Bayesians at the article’s end seems to misunderstand the issue in a way which is (ironically) similar to the misunderstandings of others highlighted earlier in the piece.

Fixes to python.sty

Tue, 09 Mar 2010 10:41:00 +0000

I use python.sty, which provides a python environment to TeX whose contents are evaluated when the TeX is compiled. For example the following:

\begin{python}
x = 'hello'
print r'\section{', x, '}'
\end{python}

will effectively compile as \section{hello} in your TeX. I’ve made a small patch to the file which makes the following changes

Allows the % sign to be used within the python environment (this is just a \catcode oversight in the original).
Defines a \setpythoninterpreter macro which lets you set your python interpreter; for example if you have a script which requires python 2.6 preface it with \setpythoninterpreter{python2.6}. In fact, you could use this to set any executable on the path, so really watch out; a malicious document could have \setpythoninterpreter{rm -rf /}!

Perhaps ideally this should be refactored as script.sty and provide a primitive like this:

\begin{script}[python2.6]
print r'Hello \LaTeX!'
\end{script}

My TeX-fu doesn’t stretch to this, unfortunately. Anyway, the comment fix just requires the line

\begingroup \catcode`\^^M=12%

to become

\begingroup \catcode`\^^M=12 \catcode`\%=12 %

To get the second (dangerous) feature, add these two lines after the ProvidesPackage

\newcommand{\python@executable}{python}
\newcommand{\setpythoninterpreter}[1]{\renewcommand{\python@executable}{#1}}

And then to change the line

\immediate\write18{cat \@pythoninclude\space\jobname.py | python > \jobname.py.out 2> \jobname.py.err}

by replacing python with \python@executable.

Check Out This Maths

Tue, 05 Jan 2010 10:37:01 +0000

Check Out This Maths

Rainbow: Camera phone is a bit lame

Tue, 22 Dec 2009 16:54:53 +0000

Rainbow:

Camera phone is a bit lame

This diagram is an explanatory image related to comments on Lots...

Wed, 16 Dec 2009 10:52:00 +0000

This diagram is an explanatory image related to comments on Lots of smoke, hardly any gun. Do climatologists falsify data?. It’s intended to correct a misunderstanding about gg’s analysis which many of the skeptical comments exhibit. gg shows a histogram of the changes in derivative in recorded temperature caused by calibration adjustments in some climate dataset.

In the diagram each white diamond is a temperature reading, and each yellow diamond is an adjusted temperature reading. The blue line is the un-adjusted trend (no change), and the cyan line the adjusted trend (an increase). The misunderstanding I hope to help with is that gg is creating a histogram of value adjustments rather than of derivative adjustments. The red numbers are the adjustment values, and if they were being binned would create the flat histogram labelled WRONG. The correct approach, which gg takes, is to find the difference in the derivative of each segment of the trend line caused by the adjustment to each of its ends. In the example, the gradient of each blue segment is 0, and of each cyan segment is +1; this gives us the green numbers and corresponding RIGHT histogram wherein the bias is clearly illustrated.

The key point which I haven’t shown here is that one cannot create an apparent warming trend without skewing the histogram of changes to the derivative rightward, but this should be apparent with a little consideration.

Virgin Media Break the Internet

Fri, 04 Sep 2009 17:09:00 +0100

A new feature introduced by Virgin Media for their broadband connections is the “Advanced Network Error Search”. This responds to DNS queries for nonexistent domains with a false result which redirects the browser to a Virgin/Yahoo search page, instead of producing an RFC-compliant no-such-domain result.

Although the intention here is to help the end user [1], the service is opt-out and will no doubt have some unintended consequences. An analogy can be made to giving way to bicycles which have no right of way (another activity which raises my ire). The smooth running of the roads depend on all road users having predictable behaviour which follows the rules. Being extra helpful in a way that is contrary to protocol typically backfires and reduces the overall quality of the service.

Virgin should be good network users and follow the protocol. If clients want friendly search they can implement it in their user-agent (c.f. Firefox’s awesomebar), without disregarding the rules and good manners which make the remarkable interoperability of the internet possible.

[1] And make Virgin Media bags of cash from advertising