Mathematica Stack Exchange is a question and answer site for users of Mathematica. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I want to plot the histogram and pdf of 2 X - 100 with X a binomial distribution, but I'm having trouble with the pdf -- I just get a line y = 0. I tried ploting a simple binomial distribution, but I don't get anything with that either and it takes so much time.

Li[n_] := 2*RandomVariate[BinomialDistribution[n, 1/2], n] - n;
Tb[n_, m_] := Table[Li[n], {i, 1, m}];
y = Tb[100, 1000];
Show[ 
 Histogram[y, 40, "PDF"], 
 Plot[PDF[2*BinomialDistribution[100, 1/2] - 100, x], {x, -10, 10}, 
   PlotStyle -> Thick]]
share|improve this question

closed as off-topic by Bob Hanlon, Kuba, MarcoB, blochwave, Öskå Oct 11 '15 at 13:16

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question arises due to a simple mistake such as a trivial syntax error, incorrect capitalization, spelling mistake, or other typographical error and is unlikely to help any future visitors, or else it is easily found in the documentation." – Bob Hanlon, Kuba, MarcoB, blochwave, Öskå
If this question can be reworded to fit the rules in the help center, please edit the question.

1  
That's (among other things) because giving ...2*BinomialDistribution[100, 1/2]-100... as the argument to PDF is nonsense. I suggest you avail yourself of the documentation to understand how to properly utilize the probability functions. – ciao Oct 9 '15 at 8:15
up vote 3 down vote accepted

As commented, you're not using the functions properly. I think what you're after is:

DiscretePlot[PDF[TransformedDistribution[2*z - 100, 
                 z \[Distributed] BinomialDistribution[100, 1/2]], x], {x, -10, 10}]

enter image description here

Note the use of DiscretePlot - the binomial is a discrete distribution, so a discrete plot is appropriate. You can cajole things to use Plot, but that's goofy IMO...

share|improve this answer
    
@ciao...the quick or the dead...just deleting my response :) – ubpdqn Oct 9 '15 at 8:21
    
@ubpdqn: Lol, once again, you cause me to spit-laugh my tea onto my netbook. Cleaning now.... – ciao Oct 9 '15 at 8:23
    
"…but that's goofy…" - Hyuck! :) – J. M. Oct 9 '15 at 9:31

Not the answer you're looking for? Browse other questions tagged or ask your own question.