Estimation problem.

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.

Moderators: EViews Gareth, EViews Moderator

jayjalvi
Posts: 4
Joined: Wed May 30, 2012 7:38 am

Estimation problem.

Postby jayjalvi » Wed May 30, 2012 7:46 am

I am trying to estimate log(TC) = β1 + β2 log(Q) + β3 log(p1) + β4 log(p2) β5 log(p3) +e

Where p1 to p3 are factors prices for inputs of a firm being wage, capital and fuel respectively).

I am trying to Estimate the equation by the least-squares method but I havnt done log equations before. Any help would be highly appriciated. Also how do we plot squared of residual from the said equation again log(Q) with squared residual on y axis?

Thanks a lot in advance. I am still learning eviews.

FIle is attached.
Attachments
electricity.wf1
(16.41 KiB) Downloaded 190 times

EViews Gareth
Fe ddaethom, fe welon, fe amcangyfrifon
Posts: 13604
Joined: Tue Sep 16, 2008 5:38 pm

Re: Estimation problem.

Postby EViews Gareth » Wed May 30, 2012 7:55 am

Just estimate it in the same way you would estimate a non-log equation, but rather than typing in your variables type in log(variable) instead.

jayjalvi
Posts: 4
Joined: Wed May 30, 2012 7:38 am

Re: Estimation problem.

Postby jayjalvi » Wed May 30, 2012 8:01 am

log(tc) c log(Q) log(wage) log(capital) log(fuel)

I tried this and it came up with an error saying insuffiecnt number of observations and after several attempts it came up with this.

Dependent Variable: LOG(TC)
Method: Least Squares
Date: 05/31/12 Time: 01:00
Sample: 1 145
Included observations: 145

Variable Coefficient Std. Error t-Statistic Prob.

C -3.526503 1.774367 -1.987471 0.0016
LOG(Q) 0.720394 0.017466 41.24448 NA
LOG(WAGE) 0.436341 0.291048 1.499209 0.1361
LOG(CAPITAL) -0.219888 0.339429 -0.647819 0.5182
LOG(FUEL) 0.426517 0.100369 4.249483 0.0000

S.E. of regression 0.392356 Akaike info criterion 1.000578
Sum squared resid 21.55201 Schwarz criterion 1.103224
Log likelihood -67.54189 Hannan-Quinn criter. 1.042286
Durbin-Watson stat 1.013062

jayjalvi
Posts: 4
Joined: Wed May 30, 2012 7:38 am

Re: Estimation problem.

Postby jayjalvi » Wed May 30, 2012 8:02 am

What I am not sure about it now is that if the output is correct after that error that I got. :(

Thanks a lot for your reply it atleast got me till here :)

Could you please help me with my 2nd concern as well? ABout plotting the squared residuals?

EViews Gareth
Fe ddaethom, fe welon, fe amcangyfrifon
Posts: 13604
Joined: Tue Sep 16, 2008 5:38 pm

Re: Estimation problem.

Postby EViews Gareth » Wed May 30, 2012 8:19 am

Make a series of squared residuals, put it in a group with the other variables you want, then make a graph out of them.

jayjalvi
Posts: 4
Joined: Wed May 30, 2012 7:38 am

Re: Estimation problem.

Postby jayjalvi » Wed May 30, 2012 8:34 am

I already have a series called resid in my workfile and I want to plot it again log(Q) . How do I go about with Sqyared of Residual using the series resid? SOrry for being a pain but I am just trying to get my head around it. I don't want to look annoying just that I can't understand. COuld you please, please explain it a little more.

I shall be very thnakful!

EViews Gareth
Fe ddaethom, fe welon, fe amcangyfrifon
Posts: 13604
Joined: Tue Sep 16, 2008 5:38 pm

Estimation problem.

Postby EViews Gareth » Wed May 30, 2012 9:42 am

Series residsq = resid^2


Return to “Estimation”

Who is online

Users browsing this forum: No registered users and 1 guest