Problem Set 1 Troubleshooting
Log Files Save in text format for readability: log using ps1.log, replace or: log using ps1, text
Handling Missing Values -By default, Stata excludes all observations marked with a period (.) from subsequent statistical analysis. -Best practices: -Recode appropriate survey responses to missing. Safest: replace v1 =. if v1 == 6 -Do not drop observations with missing values. -Be careful not to recode missing values by accident.
Handling Missing Values Problematic: gen dummy1 = 0 replace dummy1 = 1 if v1 == 4 | v1==5 Safe: gen dummy1 =. replace dummy1 = 1 if v1 == 4 | v1==5 replace dummy1 = 0 if v1 <= 3 gen dummy1 = 1 if v1 == 4 | v1==5 replace dummy1 = 0 if v1 <= 3
Handling Missing Values Stata handles ‘.’ as higher than any integer value. Will recode missing observations: replace dummy1 = 1 if v1 > 6 Safe: replace dummy1 = 1 if v1 > 6 & v1 !=.
Optional: PS2 Time Saver Stata supports loops: foreach x of numlist { sum spending if year==`x', detail } foreach x of varlist gdpcap pop taxhead race* { gen log_`x’ = log(`x’) sum `x’, detail hist `x’, name(`x’) }