Change point problems: Problems with chronologically ordered data collected over the period during which there is known to have been a change in the underlying data generation course. Interest then lies in, retrospectively, making the inferences about the time period or position in the sequence in which the change occurred. A well known example is the Lindisfarne scribes data in which a count is made of the occurrences of the certain type of pronoun ending observed in 13 chronologically order edmedievalmanu scripts thought to be the work of more than one author. A plot of data shows strong evidence of a change point in the below drawn figure. An easy example of the possible model for such a problem is as follows

  

 

Interest would centre on estimating parameters in the model specifically the change point, τ