Pathologically Eclectic Rubbish Lister PerlMonks

### RE (tilly) 2 (no assumptions): Spooky math problem

by tilly (Archbishop)
 on Nov 02, 2000 at 02:12 UTC ( #39518=note: print w/replies, xml ) Need Help??

in reply to RE: Spooky math problem
in thread Spooky math problem

Read the problem again. Were such assumptions needed you can be sure I would have stated them. But they are not.

The key is that your random number needs some chance of falling in the interval between the numbers. As long as you can guarantee that, you get better than even odds. But it turns out that is not hard to guarantee. However if the two numbers differ by, say, 1 from each other it turns out that on average you are ahead by all of zero percent (very large tails with probabilities near 50% dominate). So against a mildly malicious opponent you - on average - don't come out ahead. But that is an average across an infinite number of situations, every last one of which you came out ahead in. (Infinity has lots of strange stuff like this.)

Again, the probability of your winning depends on the two numbers that I have. But it is always better than even. And you can guarantee that no matter how I tried to produce my numbers.

• Comment on RE (tilly) 2 (no assumptions): Spooky math problem

Create A New User
Node Status?
node history
Node Type: note [id://39518]
help
Chatterbox?
 [Discipulus]: how I can tell in which perl version was included List::Util 1.29 ? [Discipulus]: to specify use 5.0.x to be sure to have pairmap from the module.. [Corion]: Discipulus: I think Module::Corelist ( or corelist ) can tell you that [Corion]: Meh - Module::CoreList [choroba]: Just use List::Util 1.29 [choroba]: Be kind to people using old Perl with newer version of the module [Corion]: But why not simply specify 'List::Util' => 1.29 in your prerequisites? People might install a more recent version of the module into their Perl [Corion]: (what choroba said)

How do I use this? | Other CB clients
Other Users?
Others studying the Monastery: (6)
As of 2017-05-25 09:17 GMT
Sections?
Information?
Find Nodes?
Leftovers?
Voting Booth?
My favorite model of computation is ...

Results (187 votes). Check out past polls.