To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.off-topic.geekOpen lugnet.off-topic.geek in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Off-Topic / Geek / 4173
4172  |  4174
Subject: 
Re: math question (or pattern... whatever...)
Newsgroups: 
lugnet.off-topic.geek
Date: 
Mon, 3 Mar 2003 21:13:50 GMT
Viewed: 
256 times
  
On Mon, Mar 03, 2003 at 08:54:01PM +0000, David Koudys wrote:
r(1) r(2)
r(1) b
r(1) w
r(2) b
r(2) w

(b w being still eliminated due to red already being in your hand) that a
last possible combination:

r(2) r(1)

fits into the mix, so 2 out of 6, which still equals 33 percent

Any stats people out there that could shed logic on this?

I'm not a stats person, but I agree with your friend.  r(2) r(1) is the
same as r(1) r(2), because order doesn't matter.  If it does, then you
end up with more combos (w r(2), etc)...

--

that's what I was going to say.  But, I decided to run a small
simulation:

$ perl -le '
$rr = 0;
$count = 0;
for (1..10000) {
  $count ++;
  @bag = qw/r r w b/;
  $hand = "";
  for (1..2) {
    $pos = int(rand($#bag));
    $hand .= $bag[$pos];
    splice @bag, $pos, 1;
  }
  $rr++ if $hand eq "rr"
}
print "$rr/$count = ", $rr/$count;
'
3391/10000 = 0.3391

so, once again, I learn I don't quite understand statistics as I think
I do.  :)

--
Dan Boger
dan@peeron.com



Message has 2 Replies:
  Re: math question (or pattern... whatever...)
 
(...) Wow! You wrote a program! Thanks Dan! Again I'm impressed with the knowledge and skills of those that partake in LUGNET! Adding to my case, Dave K (22 years ago, 3-Mar-03, to lugnet.off-topic.geek)
  Re: math question (or pattern... whatever...)
 
(...) I don't quite get why this works-- if you're doing rand($#bag), won't that always pick r, r, or w for the 1st value? Hence, theoretically, you could pick "wb", which isn't in your sample set... on the other hand, you're increasing the chance (...) (22 years ago, 3-Mar-03, to lugnet.off-topic.geek)

Message is in Reply To:
  math question (or pattern... whatever...)
 
k, here's something that came across my desk... you have a bag with 4 marbles in it. 2 of the marbles are red 1 marble is white 1 marble is blue you reach in and grab 2 random marbles you open up your hand a bit to only see the colour of one of (...) (22 years ago, 3-Mar-03, to lugnet.off-topic.geek)

61 Messages in This Thread:




















Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR