Variance ratio and z*

[markeepa28]

Hello, i m currently finishing my dissertation(and my MSc) and the last test I have to run is Variance ratio . I have as sample stock returns and I choose the option of variance ratio (2,4,8,16) . I may studied accounting and finance but i dont know how this test works exactly. I am trying to figure it out ,how i m gonna estimate my Z* and when I reject the values. I have seen tables from other dissertations and they estimate z*. Could anybody help me...!?