Don't understand Stats Prob: Markov chain has transition matrix...

Joystar77

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A Markov chain has transition matrix

1/3 0 2/3 0 0

0 1/2 0 1/2 0

3/4 0 1/4 0 0

0 3/4 0 1/4 0

1/3 0 1/3 0 1/3


Analyze the state space (reducibility, periodicity, recurrence, etc), and discuss the
chain's long run behavior.
 
A Markov chain has transition matrix

\(\displaystyle \begin{pmatrix}1/3 & 0 & 2/3 & 0 & 0 \\
0 & 1/2 & 0 & 1/2 & 0 \\
3/4 & 0 & 1/4 & 0 & 0 \\
0 & 3/4 & 0 & 1/4 & 0 \\
1/3 & 0 & 1/3 & 0 & 1/3 \end{pmatrix}\)


Analyze the state space (reducibility, periodicity, recurrence, etc), and discuss the
chain's long run behavior.
After reading the reference given by Denis,
Denis said:
I notice that your matrix does NOT have columns that sum to 1, so that sum of elements in the state vector is not conserved. Is it possible you have entered the Transpose of the transition matirx? What definitions are you using?

What I was going to suggest is that you calculate the first few powers of the matrix and look for patterns.
 
Hello, Joystar77!

\(\displaystyle \text{A Markov chain has transition matrix: }\;A \;=\;\begin{bmatrix}\frac{1}{3}&0&\frac{2}{3} &0&0 \\ 0&\frac{1}{2}&0&\frac{1}{2}&0 \\ \frac{3}{4}&0&\frac{1}{4}&0&0 \\ 0&\frac{3}{4} &0&\frac{1}{4}&0 \\ \frac{1}{3}&0&\frac{1}{3}&0& \frac{1}{3} \end{bmatrix}\)
\(\displaystyle \text{Discuss the chain's long run behavior.}\)

\(\displaystyle \text{Let }\,X \,=\,\begin{bmatrix}a\\b\\c\\d\\e \end{bmatrix}\:\text{ where }\:AX \:=\:X\:\text{ and }\:a+b+c+d+e \:=\:1\)

\(\displaystyle \text{We have: }\;\begin{bmatrix}\frac{1}{3}&0&\frac{2}{3} &0&0 \\ 0&\frac{1}{2}&0&\frac{1}{2}&0 \\ \frac{3}{4}&0&\frac{1}{4}&0&0 \\ 0&\frac{3}{4} &0&\frac{1}{4}&0 \\ \frac{1}{3}&0&\frac{1}{3}&0& \frac{1}{3} \end{bmatrix} \begin{bmatrix}a\\b\\c\\d\\e\end{bmatrix} \;=\;\begin{bmatrix}a\\b\\c\\d\\e \end{bmatrix}\)

. . . \(\displaystyle \begin{bmatrix}\frac{1}{3}a + \frac{2}{3}c &=& a \\ \frac{1}{2}b + \frac{1}{2}d &=& b \\ \frac{3}{4}a + \frac{1}{4}c &=& c \\ \frac{3}{4}b + \frac{1}{4}d &=& d \\ \frac{1}{3}a + \frac{1}{3}c + \frac{1}{3}e &=& 3 \end{bmatrix}\)

. . . . \(\displaystyle a +b+c+d+e \;=\;1\)


\(\displaystyle \text{Solve the system: }\:\begin{Bmatrix}a &=& \frac{1}{6} \\ b &=& \frac{1}{4} \\ c &=& \frac{1}{6} \\ d &=& \frac{1}{4} \\ e &=& \frac{1}{6} \end{Bmatrix}\)

\(\displaystyle \text{I'll let }you\text{ interpret this result.}\)
 
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