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I know that you can add equations or identities to a model using .merge ior .append but is there a way of removing equations or identities from an existing model?

Unfortunately not (at least not in a program, you can always delete them interactively with the mouse).

I guess the model object has that problem when programming - We cannot handle the equations separately and delete them or for example, changing them from stochastic with a s.d. to indentity or on the other way round, isn´t it? If so, it would be nice if this could be improved

Indeed.

Hello,

I do not think this is such a problem. having to rebuild the model each time allows you to access a full model specification and visualize its content (with explanatory comments). It gives you a better control of the process.

A series of append / delete could become quite confusing very fast.

Jean Louis Brillet.

I'd like to add my support for the request to add the ability to delete one or more equations from an existing model. In working in EViews with a variety of models, some of whose equations are estimated outside of EViews, I frequently find it necessary to replace equations (to test an alternative specification; to include a different policy rule; to avoid unruly "tail" behavior in stochastic sims, etc). Although in many cases it's straightforward to create a model without the equation that needs to be replaced and then to append or merge the new equation, there are times that this approach is limiting. For such situations we have a subroutine that uses the equation and text views of a model to find and delete an equation's text and then uses the "t" option of the merge procedure to create a model without the equation. Having something like this built into EViews itself would be a bit cleaner.

If anyone wants the subroutine, I'd be happy to post it, after making it a bit more user friendly.

It is high on our list.

This feature would be very welcomed here as well. I have a problem trying to understand why some feature exist only in interactive mode. Is that so complicated to also have a command or function for each interactive feature ?

It is simply much more complicated to refer to an individual equation in a model by command than with a mouse.

fbrayton wrote:I'd like to add my support for the request to add the ability to delete one or more equations from an existing model. In working in EViews with a variety of models, some of whose equations are estimated outside of EViews, I frequently find it necessary to replace equations (to test an alternative specification; to include a different policy rule; to avoid unruly "tail" behavior in stochastic sims, etc). Although in many cases it's straightforward to create a model without the equation that needs to be replaced and then to append or merge the new equation, there are times that this approach is limiting. For such situations we have a subroutine that uses the equation and text views of a model to find and delete an equation's text and then uses the "t" option of the merge procedure to create a model without the equation. Having something like this built into EViews itself would be a bit cleaner.

If anyone wants the subroutine, I'd be happy to post it, after making it a bit more user friendly.

I'd love this subrountine! Could you please post it?

It might be part of FRBUS:
https://www.federalreserve.gov/econres/ ... ackage.htm