This is not a bug, but an intentional change for compatibility with Matlab (http://www.gnu.org/software/octave/NEWS-3.html): lambda is now the mean rather than 1/mean, so in your case you need to use lambda=10.
Such changes were also made to the gamma and normal distributions. ** Changed in: octave3.0 (Ubuntu) Status: New => Invalid -- Exponential distribution functions are broken https://bugs.launchpad.net/bugs/294570 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs