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Payoff definitions are simple text files and you can also modify them in any text editor.  

The file consists of two kinds of entry: payoff element type specifications, followed by payoff elements themselves. For example:

*P

profit/1

the type

an element

is a policy payoff that will maximize the (accumulated flow) of profit.

You can mix types:

*P

profit/1

*PF

terminal value of assets/1

terminal value of environment/1

The type specification, like *P or *PF here, applies to all subsequent elements, until another type is encountered. You can repeat the type before each line, but it is not necessary.

If you are not using timing and distribution modifiers, like *PF or *CK, you can write *Policy for policy and *Calibration for calibration (only the first letter is significant).

Example

 

*CR

Var1|data1/scale1

*CK

Var2|data2/variance2

*PLI

Constraint/-1

 

The first element specifies a robust absolute error criterion for Var1.

The second element specifies a least-squares error criterion for Var2, with measurement variance variance2, which may also be estimated as an optimization control parameter.

The third element imposes a penalty on a Constraint parameter, perhaps reflecting a prior or an inequality constraint, calculated only at initial time.