Viterbi Calculator

[HugoCarr]

Hello,

I am using the JAHMM package to try and replicate in Java some results
that I got in Matlab. Essentially what I am looking for is the stage
just before the Viterbi path is calculated. Usually you are given the
most probable sequence of states given an input.

eg: a bistable system is observed with a small amount of noise
1 1 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 1 1 1 1 1 0 1 1 1
the viterbi path predicting what the signal looks like without noise
might be
1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1

What I am interested in is the array of probabilities for the states
that the viterbi path uses to create the path. Something along the
lines of:

1 1 0 1 1 0 0 0 ...
1 1 1 1 1 0 0 0 ...
0.9 0.9 0.7 0.9 0.9 0.5 0.1 0.1 ...
0.9 0.1 0.3 0.1 0.1 0.5 0.9 0.9 ...

Where the first line is the observation, the second line is the
viterbi path and the third and fourth lines represent the
probabilities that the actual state is either 1 or 0

Thanks in advance,
Hugo Carr

[HugoCarr]

sorry the first 0.9 on the last number of lines should be 0.1

[HugoCarr]

Not to worry

I have just hacked the source of the ViterbiCalculator with a
getDelta() function

[Jean-Marc François]

Ok, well done.

JM

> --
> You received this message because you are subscribed to the Google Groups "Jahmm HMM library" group.
> To post to this group, send email to jahmm-...@googlegroups.com.
> To unsubscribe from this group, send email to jahmm-discus...@googlegroups.com.
> For more options, visit this group at http://groups.google.com/group/jahmm-discuss?hl=en.
>

[Sanish Rai]

Hi HugoCarr,

Can you also help me with that? 

I also need similar data, to find the probabilities of all the states for the given observation.

Thanks.