Add new series to panel data after filtering

[student_m]

Hi,

I am working with panel data and have runned a lot of filters to exclude unwanted observations, such as data before year 2000 and financial firms etc. However, just noticed that I need to add an extra series to the data set. Will this mess up my already filtered datas? Do I have to run the filters again? How do I remove the unwanted observations from the new series such that it will fit the already filtered data set?

[EViews Gareth]

Since EViews doesn't have "filters", perhaps you could go into more detail about what you have done?

[student_m]

I am working with a data set too big to handle in excel, or at least my version of excel. The data set consist of different accounting statements from different firms over a period from 1994 to 2011. However, to "clean" the data set to make it fit my purpose of use, I had to remove all data from 1994 to 2000, I had to remove all firms with negative operating income, remove firms with no employees etc. I used proc contract current page and "if" to do this. But today I noticed that I was missing two types of accounting statements. I will be able to get these, but how can I include them in the already existing data set? Because all the "filters" I have runned on the exsisting data set removing firms that do not fit for my purpose should also apply for the two new series of acounting statements.

[EViews Gareth]

Hard to say without seeing the data. What you're describing is too abstract at the moment.

[student_m]

I can try to give an simpler example. Say I have data of operating income for 3 different firms from the period 1990 to 1995. I import these datas into eviews, creating a workfile of panel data. I then remove (drop) the observations for the year 1990 by using "proc" --> "contract current page" --> 1991 1995. Then I remove (drop) one of the firms due to the reason it has negative operating income by using "proc" --> "contract current page" --> 1991 1995 if operating_income > 0. This removes one of the firms. Thus, after have done these two commands, my work file consist of operating income from 2 firms for the period 1991 to 1995. But then I wish to add a new serie to the workfile, say "long term debt". I have the observations of debt for the 3 firms(same firms) over the period 1990 to 1995. What will happen if I import this "long term debt series" into the work file? Since this series consist of 3 firms from the period 1990 to 1995, but my workfile only consist of 2 firms from the period 1991 to 1995. Will eviews correct the new "long term debt" series by dropping observations from year 1990 and the one firm?

[EViews Gareth]

Yes, it will.