Tim said:

You mean that for every £100 down, you get back £90?

That's right. Expected money after investing £100.

Are you sure it is "11+" times luckier?

Well, if I start with 50000 then man-on-the-street 90% would give you 45000.

If I win 500000 then that is 500000/45000 = 11.1 times more money QED 11+

times luckier. Yes, that makes sense to me. Perhaps I should define luck

more formally. Luck (as far as I am concerned) is the factor by which the

expected return (if it can be numerically quantified) must be multiplied to

give the actual return. Thus someone who (in a particular event) has Luck >

1 has been lucky and someone who has Luck < 1 has been unlucky.

Man-on-the-street (mentioned above) ALWAYS (!) has luck of 1. I bet some

boring bloody actuary is going to tell me that a statistician decided to do

it a different way in about 1920. Never mind.

Take another example:

You toss a coin twenty times & get 10 heads & ten tails. The game was to

get as many (say) heads as possible, hence you only have average luck.

I toss a coin twenty times & get 20 heads. Wahaaaaay! I win. But, more

importantly, would you say that my luck is *twice* yours? What would I have

got if I was *three* times as lucky?? ( ... or 10 times?! )

Aha! Lets apply the theory above. Someone who gets 20 has luck of 20/10 = 2.

Quite lucky. But you can't work it round the other way and say "what if he

was three times as lucky?". Luck (as far as I'm concerned) can be calculated

for a particular event, but is not some sort of intrinsic personal variable.

The idea of someone walking into a room with a luck factor of 4 and cleaning

out a casino with certain knowledge that he is going to do so is absurd

isn't it? The reason for this is that someone's luck can only be calculated

retrospectively (otherwise it rides a coach and six through basic

probability theory as I (naively) understand it).

Lets have some more examples. There must be a contradiction in the nonsense

I've just written. Surely!

John.

PS. Remember that Red Dwarf when lister injected luck. He went and hammered

about 8 digits into a keypad and opened a door. His luck there was something

obscene. But if he had typed in 10 digits (say) it would have been even more

obscene . So luck would have to mysteriously vary due to the difficulty of

the task achieved, which doesn't bode well for the intrinsic luck argument.