MarkovProcessProperties bugs
- To: mathgroup at smc.vnet.net
- Subject: [mg132132] MarkovProcessProperties bugs
- From: Lee Altenberg <pzone3141 at dynamics.org>
- Date: Fri, 20 Dec 2013 05:35:02 -0500 (EST)
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Mathematica 9 appears to have this bug:
MarkovProcessProperties[
DiscreteMarkovProcess[
initVec, {{0, 1/2, 1/2, 0}, {1, 0, 0, 0}, {0, 0, 0, 1}, {1, 0, 0,
0}} ], "Aperiodic"]
returns "False".
However, the stochastic matrix {{0, 1/2, 1/2, 0}, {1, 0, 0, 0}, {0, 0, 0, 1}, {1, 0, 0,
0}} is primitive, i.e. irreducible and aperiodic. The positive diagonal entry 1/2 at [[2,2]] guarantees aperiodicity.
Similarly, "False" is returned on {{0, 1/2, 1/2, 0}, {1, 0, 0, 0}, {0, 0, 1/2, 1/2}, {1, 0, 0, 0}}
while "True" is returned on
{{0, 1/2, 1/2, 0}, {1/2, 1/2, 0, 0}, {0, 0, 1/2, 1/2}, {1, 0, 0, 0}} .
All of these examples, however, are aperiodic.