title: Posterior probability after robot movement
body: <p>Suppose robot moves in cells and there are 5 cells. Their dist. is as follows:
  |   1/9  |   1/3  |   1/3  |   1/9  |  1/9  |</p>
  
  <p>The robot moves one cells towards right. And the world is cyclic. When it moves to the most right cell, it return back to the most left one. </p>
  
  <p>And the posterior probability after one cell movement is as follows:
  |  1/9   |   1/9  |   1/3  |   1/3  |   1/9 |</p>
  
  <p>The following diagram is a good illustration. 
  <img src="https://i.stack.imgur.com/IdJqV.png" alt="enter image description here"></p>
  
  <p>Can any guy tell me why the posterior probability shifts to the right one cell?
  Thanks in advance!</p>