Hello
My data is panel data with strongly balanced . As I want to know the effect of lpi on export and import I have chosen export and import as dep vars and lpi, gdp, distance and dummy as indep vars. The summaries of my data as follow as
Because the cases with the export or import value is equal to 0 account for about 18% of total obs so I decided to use pplm to analyse. My equation becomes like this
Ex= a ln(gdp) + b ln(dis) + c ln( lpi) + e. dummy ( landlocked)
But there are some missing data on lpi because in some years in some specific countries , LPI were not collected
So I wonder whether my equation is suitable or not. If not what is equation should I use?
Please give me advice
Thank so much
My data is panel data with strongly balanced . As I want to know the effect of lpi on export and import I have chosen export and import as dep vars and lpi, gdp, distance and dummy as indep vars. The summaries of my data as follow as
Code:
Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- export | 1,328 833.446 3024.465 0 41549.71 import | 1,328 837.313 3961.817 0 58532.57 distance | 1,328 8860.618 4304.137 478.553 19228.99 gdp | 1,328 4523.65 16524.65 1.97454 196236.7 landlocked | 1,328 .2108434 .4080611 0 1 -------------+--------------------------------------------------------- lpi0 | 1,262 2.879012 .5787635 1.598322 4.225967 lpi1 | 1,262 2.691696 .5987479 1.111111 4.20779 lpi2 | 1,262 2.754088 .6829058 1.237654 4.439356 lpi3 | 1,262 2.846396 .5248384 1.362654 4.235 lpi4 | 1,262 2.828908 .608916 1.394253 4.31065 -------------+--------------------------------------------------------- lpi5 | 1,262 2.886015 .6297591 1.513605 4.377678 lpi6 | 1,262 3.253649 .5854234 1.665079 4.795714
Ex= a ln(gdp) + b ln(dis) + c ln( lpi) + e. dummy ( landlocked)
But there are some missing data on lpi because in some years in some specific countries , LPI were not collected
Code:
gen ll1=ln(lpi1) (66 missing values generated)
Please give me advice
Thank so much
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