Why I’m jealous of my eldest son

In his recent blog-post The pillars of tax wisdom, Tim Harford (author of The Undercover Economist) discusses “James Mirrlees — now a Nobel laureate — who tried to figure out what could be said about optimal income taxation. One of his conclusions, surprising to him as much as anyone else, was that an optimal income tax might impose flat or even falling marginal tax rates.”

Osborne’s spending review

So what do we all think?

My, and my wife’s, submissions on the NHS Agenda

Another day, another attempt to slow our government’s dismantling of everything of value in this country. Yesterday it was freedom of information, the day before it was the BBC; today it’s the NHS.

Turns out the Government has proposed “a new mandate to NHS England for this Parliament“, and asked for comments … but very, very quietly, in case someone hears and actually submits some.

My comments on the Government’s call for evidence on Freedom Of Information

The UK government is presently running a call for evidence on Freedom of Information. (It closes at midnight tonight, so if you want to contribute, get your skates on! Here’s a simple way to do it.)

A coding confession

I just found this code in one of my source files:

for (HashMap.Entry<String, Void> e2: map.entrySet()) {
  if (eventName.equals(e2.getKey())) {
    m.handle(eventName, data);
  }
}

Yes. I was iterating through the keys in a HashMap to find out whether the one I wanted was there. But the whole point of a HashMap is that looking up a key is an O(1) operation.

What I should have written is:

if (map.containsKey(eventName)) {
  m.handle(eventName, data);
}

The moral of the story: I can be really, really dumb. (But hey, at least my code worked!)

How to measure the strength of the economy, redux

Last month, I argued the point (admittedly at rather more length than necessary) that GDP does not measure what we’re interested in. I’m currently reading Tim Harford’s fascinating book The Undercover Economist [amazon.com, amazon.co.uk] — which, by the way I highly recommend — and I was pleased to discover that he agrees with me.

Application to coach the England rugby team

I just sent this letter off to the Rugby Football Union:

Marquise au Chocolat

I generally don’t like to make desserts. I tend not to eat them in restaurants, either. The question I always ask myself is, is this dessert going to be better than a bar of chocolate? Usually, the answer is no. But for marquise au chocolat, the answer is a definite yes.

Is the stock market zero-sum?

Suppose I buy a share in Microsoft from you at $400. Microsoft do well, and it increases in value to $500. At that point, I don’t want to push my luck any further, and sell my share for $500. It just so happens that you are the buyer.

In this scenario I have made $100 by “playing the markets”. But you have lost $100: you received $400 and paid $500, and ended up holding the same share that you started with. In effect, I have taken $100 from you. (Thanks!)

That was a zero-sum transaction, because your loss exactly cancelled out my win.

My question: is the whole stock-market zero-sum?

How to drive away a repeat customer, in four identical steps

Step 1. Offer to sell the customer an extended warranty
Step 2. Offer to sell the customer an extended warranty
Step 3. Offer to sell the customer an extended warranty
Step 4. Offer to sell the customer an extended warranty

This is, evidently, the strategy of Bosch, a white-goods manufacturer with a good reputation for quality and reliability, but who I will quite possibly never buy another device from because they will not stop spamming me.