I am analyzing the impact of two FTAs (signed between two countries only, one between country A and country B, the other between country A and country C) on bilateral trade. The results are turning insignificant. Should I include other FTAs signed by these countries and other countries also to prevent omitted variable bias? Can I include the FTA dummy which covers all FTAs with value 1 for country pairs having FTA between them? Kindly suggest to me possible solutions.
Thank you.
Thank you.