Dynamic programming and Bellman Equation

 

[Todayfs model cannot be solved by guess and verify.]

 

We consider the following maximization problem

         

where

 on probability of p11 from state 1 to state 1 and p12 from state 2 to state 1

 on probability of p21 from state 1 to state 2 and p22 from state 2 to state 2

 

Here, p21=1-p11 and p22=1-p12. They are exactly the same as yesterdayfs.

 

However, p11 and p12 are functions of labor. Let us describe them as

 

p11(lt) and p12(lt).

 

The corresponding Bellman equations are

 

and

We guess

 

 and

 

That is

and

 

FOCfs w.r.t. are

 

        (*)

and

        (**)

 

They are almost the same as yesterdayfs but in terms of probability functions.

 

On the other hand, FOCfs w.r.t. are

For the first one

 

 (***)

 

For the second one, in the same way,

 

       (****)

 

The rest is almost the same as yesterdayfs but we cannot get constant labors.

 

That is the problem. Both E and G in value functions are no longer solvable

 

in terms of parameters and constants. They depend on  by (***) and (****)

 

that also depend on k. That is a contradiction. We fail to guess and verify.

 

We could solve as FOCfs as they are but we cannot apply the guess and verify.