. xtunitroot llc   lnr
Levin-Lin-Chu unit-root test for lnr
------------------------------------
Ho: Panels contain unit roots               Number of panels  =     29
Ha: Panels are stationary                   Number of periods =     19
AR parameter: Common                        Asymptotics: N/T -> 0
Panel means:  Included
Time trend:   Not included
ADF regressions: 1 lag
LR variance:     Bartlett kernel, 8.00 lags average (chosen by LLC)
------------------------------------------------------------------------------
                    Statistic      p-value
------------------------------------------------------------------------------
Unadjusted t         2.6257
Adjusted t*          7.5893        1.0000
------------------------------------------------------------------------------
.

xtunitroot llc   lne
Levin-Lin-Chu unit-root test for lne
------------------------------------
Ho: Panels contain unit roots               Number of panels  =     29
Ha: Panels are stationary                   Number of periods =     19
AR parameter: Common                        Asymptotics: N/T -> 0
Panel means:  Included
Time trend:   Not included
ADF regressions: 1 lag
LR variance:     Bartlett kernel, 8.00 lags average (chosen by LLC)
------------------------------------------------------------------------------
                    Statistic      p-value
------------------------------------------------------------------------------
Unadjusted t        -4.7380
Adjusted t*         -3.2754        0.0005


这个结果怎么看，，如果有单位根是不是要加入一阶滞后变量，谢谢