fixed and random effects estimation

[indah284]

Hi, guys.

I need your help for my problem. I'm estimating a gravity model. It's about export in 4 cross sections over 10 years. I have variables which vary in time and cross section and I have constant variable (distance between two countries). I have read that I can't estimate with fixed effect because of constant variable, but later I try to estimate with random effect and it doesn't work. I get error message "Random effects estimation requires number of cross section>number of coefs for between estimator for estimate of RE innovation variace."
I'm using eviews 8.

So what should I do with this? I hope you could help me because I have to finish my thesis.
Thank you.