------------------------------------------------------------------------------------------------------------- * osa 2 . xtset ID year Panel variable: ID (strongly balanced) Time variable: year, 1950 to 2004 Delta: 1 unit * osa 3 . xtline EXP . xtline EXP, byopts(yrescale) * osa 4 . gen l_exp=ln(EXP) * osa 5 . xtline l_exp * osa 6 . xtunitroot ips l_exp, trend Im–Pesaran–Shin unit-root test for l_exp ---------------------------------------- H0: All panels contain unit roots Number of panels = 5 Ha: Some panels are stationary Number of periods = 55 AR parameter: Panel-specific Asymptotics: T,N -> Infinity Panel means: Included sequentially Time trend: Included ADF regressions: No lags included ------------------------------------------------------------------------------ Fixed-N exact critical values Statistic p-value 1% 5% 10% ------------------------------------------------------------------------------ t-bar -1.7476 -3.000 -2.750 -2.630 t-tilde-bar -1.6620 Z-t-tilde-bar -0.5022 0.3078 ------------------------------------------------------------------------------ * osa 7 . gen dl_exp=D.l_exp (5 missing values generated) * osa 8 . xtline dl_exp * osa 9 . xtunitroot ips dl_exp Im–Pesaran–Shin unit-root test for dl_exp ----------------------------------------- H0: All panels contain unit roots Number of panels = 5 Ha: Some panels are stationary Number of periods = 54 AR parameter: Panel-specific Asymptotics: T,N -> Infinity Panel means: Included sequentially Time trend: Not included ADF regressions: No lags included ------------------------------------------------------------------------------ Fixed-N exact critical values Statistic p-value 1% 5% 10% ------------------------------------------------------------------------------ t-bar -5.6894 -2.420 -2.160 -2.020 t-tilde-bar -4.4810 Z-t-tilde-bar -8.2738 0.0000 ------------------------------------------------------------------------------ * osa 10 . xtunitroot hadri dl_exp Hadri LM test for dl_exp -------------------------- H0: All panels are stationary Number of panels = 5 Ha: Some panels contain unit roots Number of periods = 54 Time trend: Not included Asymptotics: T, N -> Infinity Heteroskedasticity: Not robust sequentially LR variance: (not used) ------------------------------------------------------------------------------ Statistic p-value ------------------------------------------------------------------------------ z 5.4802 0.0000 ------------------------------------------------------------------------------ . xtunitroot hadri dl_exp if ID==1 | ID==2 | ID==3 | ID==4 Hadri LM test for dl_exp -------------------------- H0: All panels are stationary Number of panels = 4 Ha: Some panels contain unit roots Number of periods = 54 Time trend: Not included Asymptotics: T, N -> Infinity Heteroskedasticity: Not robust sequentially LR variance: (not used) ------------------------------------------------------------------------------ Statistic p-value ------------------------------------------------------------------------------ z 1.0525 0.1463 ------------------------------------------------------------------------------ -------------------------------------------------------------------------------------------------------------