hello everyone,
i am doing my study gravity model in trade- a panel data analysis. one of the independent variable is DYPijt which denotes the absolute difference between country i's GDP per capita and country j‟s GDP per capita. the value of DYPijt in my study is negative. i am using log linear form how can i get the natural log of a negative value?
any help in this regard is really appreciable.
thanks
You would have to invent a new type of math. Natural logs are positive only.
If ALL of the values are negative, you should be able to compute an acceptable model driver. Compute the log of the absolute value instead but be sure to adjust for that calculation in your final equation.
Registration is open! SAS is returning to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. Register for just $495 by 12/31/2023.
If you are interested in speaking, there is still time to submit a session idea. More details are posted on the website.
Learn how to run multiple linear regression models with and without interactions, presented by SAS user Alex Chaplin.
Find more tutorials on the SAS Users YouTube channel.