### Is the Director of Public Prosecutions innumerate?

 It varies a lot, so Mr Starmer couldn't average it
Listening to the Today programme on Radio 4 a few days ago (5 June), I couldn't help wonder if the Director of Public Prosecutions, the exotically named Keir Starmer, struggles with numbers and particularly with statistics.

There were two issues with Mr Starmer's answers. The interviewer was trying to get Starmer to put a percentage on the point at which the prosecution service would take a case forward. What was the probability of success required before prosecuting? Starmer couldn't reply. There just, he said, had to be a reasonable chance of success. The actual percentage could vary from case to case. That's really not good enough. What does 'a reasonable chance' mean? There is an implied number in there - but he's not admitting what it is. And if it does vary from case to case, fine. But what are the criteria? It's fair enough to say there isn't a consistent percentage of likelihood across different types of case (though there needs to be a clear reason for varying it), but there needs to be a good logical reason for doing this. Without it, the justice system is anything but transparent and potential subject to misuse.

The second problem Mr Starmer has is that he clearly doesn't understand what an average is. He was asked how long it took them to consider a case and replied 'It varies a lot, so we can't come up with a average.' Well, no Mr Starmer, this is exactly when you can come up with an average. If it was always 21 days you wouldn't need an average - it is only if there is variability that you need one. Of course if it is an interesting distribution you need to tell us a bit more - the median, perhaps, and what the distribution is like. But this provides no excuse for hiding behind vagueness.

There are two possibilities here. Either Mr Starmer is innumerate or he was trying to conceal things with deliberate vagueness. Taking the kind view that no deception was involved, perhaps we can make sure that when he is replaced we get someone who has familiarity with the basics of statistics and can make sure his department is acting fairly and logically - impossible without having a grasp of those numbers.

### Why I hate opera

If I'm honest, the title of this post is an exaggeration to make a point. I don't really hate opera. There are a couple of operas - notably Monteverdi's Incoranazione di Poppea and Purcell's Dido & Aeneas - that I quite like. But what I do find truly sickening is the reverence with which opera is treated, as if it were some particularly great art form. Nowhere was this more obvious than in ITV's recent gut-wrenchingly awful series Pop Star to Opera Star , where the likes of Alan Tichmarsh treated the real opera singers as if they were fragile pieces on Antiques Roadshow, and the music as if it were a gift of the gods. In my opinion - and I know not everyone agrees - opera is: Mediocre music Melodramatic plots Amateurishly hammy acting A forced and unpleasant singing style Ridiculously over-supported by public funds I won't even bother to go into any detail on the plots and the acting - this is just self-evident. But the other aspects need some ex

### Is 5x3 the same as 3x5?

The Internet has gone mildly bonkers over a child in America who was marked down in a test because when asked to work out 5x3 by repeated addition he/she used 5+5+5 instead of 3+3+3+3+3. Those who support the teacher say that 5x3 means 'five lots of 3' where the complainants say that 'times' is commutative (reversible) so the distinction is meaningless as 5x3 and 3x5 are indistinguishable. It's certainly true that not all mathematical operations are commutative. I think we are all comfortable that 5-3 is not the same as 3-5.  However. This not true of multiplication (of numbers). And so if there is to be any distinction, it has to be in the use of English to interpret the 'x' sign. Unfortunately, even here there is no logical way of coming up with a definitive answer. I suspect most primary school teachers would expands 'times' as 'lots of' as mentioned above. So we get 5 x 3 as '5 lots of 3'. Unfortunately that only wor