## Eviews D functions

For technical questions regarding estimation of single equations, systems, VARs, Factor analysis and State Space Models in EViews. General econometric questions and advice should go in the Econometric Discussions forum.

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Eoghan
Posts: 11
Joined: Sun Mar 19, 2017 7:23 am

### Eviews D functions

I have two variables RGDP and WAGES
I'm supposed to generate two new series D_RGDP and D_WAGES using eviews D functions:
D(X) = X-X(-1)
D(X) = X(t)-X(t-1)

t and t-1 are subscripts

what would be the commands to do this?
I get syntax error/(-1) not good when i try genr series d_rgdp = grgdp-grgdp(-1) for the first one
and I'm not sure at all how to generate the second one with my variables

startz
Non-normality and collinearity are NOT problems!
Posts: 3416
Joined: Wed Sep 17, 2008 2:25 pm

### Re: Eviews D functions

Eoghan wrote:I have two variables RGDP and WAGES
I'm supposed to generate two new series D_RGDP and D_WAGES using eviews D functions:
D(X) = X-X(-1)
D(X) = X(t)-X(t-1)

t and t-1 are subscripts

what would be the commands to do this?
I get syntax error/(-1) not good when i try genr series d_rgdp = grgdp-grgdp(-1) for the first one
and I'm not sure at all how to generate the second one with my variables

any of

Code: Select all

`genr d_rgdp = grgdp-grgdp(-1) series d_rgdp = grgdp-grgdp(-1) series d_rgdp = d(grgdp)`

Just don't say both genr and series.

Eoghan
Posts: 11
Joined: Sun Mar 19, 2017 7:23 am

### Re: Eviews D functions

thanks, how would I then do the one with the D(X)=Xt-Xt-1 for wages

startz
Non-normality and collinearity are NOT problems!
Posts: 3416
Joined: Wed Sep 17, 2008 2:25 pm

### Re: Eviews D functions

Eoghan wrote:thanks, how would I then do the one with the D(X)=Xt-Xt-1 for wages

Code: Select all

`series d_wages = d(wages)`

Eoghan
Posts: 11
Joined: Sun Mar 19, 2017 7:23 am

### Re: Eviews D functions

I thought they were two different commands?
or are they the same then?
D(X)=X-X(-1) verse D(X)=Xt-Xt-1

startz
Non-normality and collinearity are NOT problems!
Posts: 3416
Joined: Wed Sep 17, 2008 2:25 pm

### Re: Eviews D functions

In EViews a number in parentheses gives a lag. You don't explicitly put in the t.

Eoghan
Posts: 11
Joined: Sun Mar 19, 2017 7:23 am

### Re: Eviews D functions

ah ok, thank you!
Do you know how I would run 10 forecasts using 200 observations each
this is to help calculate MAPE and RMSE

startz
Non-normality and collinearity are NOT problems!
Posts: 3416
Joined: Wed Sep 17, 2008 2:25 pm

### Re: Eviews D functions

That sort of thing depends on exactly what you're trying to do. You might want to read some of the online tutorials or EViews Illustrated to get a head start on how to use EViews tools.