Hello,

I have a basic modelling question related to an analysis I am running using STATA. I do realise that this is NOT a STATA-specific question however since it is impacting my research on STATA, I thought I would check. If you feel this question does not belong to this forum, please do let me know. I will check elsewhere.)

Here is my question:
1. I am investigating the impact of geographic diversification (quadratic term) on firm performance for the period 2001-2019
2. I would like to understand if there is a difference in impact of geographic diversification (quadratic term) on firm performance pre-2007 and post 2007 (ie before and after the Global Financial Crisis.)
3. Should I be modelling my research question as 2 sub-groups (pre-crisis and post-crisis) or should I be modelling it as an interaction effect of Crisis on impact of geographic diversification (quadratic term) on firm performance.

Thank you in advance.