The sale looked impressive – posters in the window guaranteed savings of “up to” 80%. Wow. We were about to go into the store when my friend asked: “But what does that mean?” Read the rest of this entry »

An article in the Liverpool Daily Post tells us that, “Beer sales fell more than 8% in the first three months of the year compared with 2008. The British Beer & Pub Association (BBPA) said 1.7m fewer pints were drunk daily from January to March than in the same period last year.”

So far, so good – that’s 1.7m fewer pints each day for 90 days (31+28+31), making a total of 153m fewer pints sold in the first quarter of 2009.

But then, a few paragraphs later, we learn this: “The BBPA’s UK Quarterly Beer Barometer showed a total of 68m fewer pints – more than 750,000 a day – were sold.”

What? This flatly contradicts the intro. So is the true figure 1.7m fewer pints daily or 750,000 pints? After all, the difference represents a hell of a lot of lager! Read the rest of this entry »

An article from this morning’s Liverpool Daily Post claims that Wirral West MP Stephen Hesford is Merseyside’s most expensive. He claimed £166,866 in expenses which, the article tells us, is “£22,000 more than the Commons average”.

That makes the average claim £144,866 (the report doesn’t define which “average” is being used, but presumably it’s the mean). Mr Hesford, we’re informed, “ran up a Parliamentary bill 16% above average last year”. Not on the quoted figures, he didn’t. The figure of 22,000 represents  a 15.2% increase over the average of 144,866 (to one decimal figure). The rule for rounding is clear – if you’re rounding a figure to whole numbers, look at the first decimal place (in this instance, it’s “2”). If it’s less than five, round down; if it’s five or greater, round up. So in this case, 15.2% becomes 15% not 16%.

What’s happened here? Well, it’s odd that Mr Hesford’s claim is given to the pound whereas the amount by which this differs from the average is given to a round figure of £22,000, clearly not the true figure.

Although other newspapers (such as The Guardian) use a rounded off figure of £144,000 for the average, the true figure according to the Daily Mail website is actually £144,176. That differs from the figure implied in the Liverpool Daily Post report by £690. Using the Daily Mail’s figure does indeed show that Mr Hesford’s expenses were 15.7% (to one decimal place) above average, and we can quite rightly round this to 16%. So the Daily Post’s article is indeed correct, but it’s figures are misleading.

The lesson? If you’re quoting figures (salaries, expenses) to the nearest pound, then do so throughout – if you suddenly change the level of accuracy (that missing £690 from the Parliamentary average is 0.48% away from the true figure), then some readers will realise that the sums don’t add up.

Naturally, we don’t want to stupify readers with the minutiae of numerical detail, but this strikes me as an example of needless imprecision – the reporter clearly had the accurate figures because they came up with the right answer (16%); so why not share that level of detail with the rest of us?

None of which makes the behaviour of some of our MPs appear less than avaricious, though.

(The above isn’t meant as a criticism of the Liverpool Daily Post in particular. I worked at this paper for many years, and it is generally more accurate than most – but as it is a paper I am familiar with, I tend to draw examples from it!).