Traceback - Viterbi Decoding of a CpG-Island HMM Step by Step

Backpointers recover the most likely hidden state path.

highlighted = computed this step

The final column has a tie

After the final A, states I and N both have value 81/2048. State order breaks the tie in favor of I.

\frac{81}{2048}=\frac{81}{2048}

Following the backpointers gives path I, I, I with joint probability 81/2048.

P(\text{I,I,I},\text{GGA})=\frac{81}{2048}