Multipliers with log-data in first differences
Posted: Mon Sep 05, 2016 4:26 am
I estimated fiscal multipliers (via Blanchard and Perotti decomposition) in levels, which is suggested by mentioned authors even if series are I(1). And I mostly got estimates that are broadly in line with relevant literature.
However, for the sake of robustness check, I want to test how would my results change if I imply the same procedure, but instead of using log levels, I will use log of first differences. This is, in the end, how textbook on time series taught us so, compared to the empirical literature (Blanchard and Perotti (2002), Perotti (2004),. etc.) => if variables are non-stationary (for example, I(1)), we should make them stationary - by calculating first differences. Problem is also that even on the internet, I couldn't find any paper at all that deals with estimation of structural VAR with log-data in first differences, with a goal to calculate multipliers.
All in all, my question is: how can multipliers, calculated by structural VAR with log-data in differences, be interpreted? (For log-data in levels it is easy -> if you increase X by one unit, what is the change in Y). And also, is there any particular reason why I couldn't find any paper dealing with this issue?
Thanks a lot in advance,
Tibius Thewad Askölääinounen
However, for the sake of robustness check, I want to test how would my results change if I imply the same procedure, but instead of using log levels, I will use log of first differences. This is, in the end, how textbook on time series taught us so, compared to the empirical literature (Blanchard and Perotti (2002), Perotti (2004),. etc.) => if variables are non-stationary (for example, I(1)), we should make them stationary - by calculating first differences. Problem is also that even on the internet, I couldn't find any paper at all that deals with estimation of structural VAR with log-data in first differences, with a goal to calculate multipliers.
All in all, my question is: how can multipliers, calculated by structural VAR with log-data in differences, be interpreted? (For log-data in levels it is easy -> if you increase X by one unit, what is the change in Y). And also, is there any particular reason why I couldn't find any paper dealing with this issue?
Thanks a lot in advance,
Tibius Thewad Askölääinounen