如下结果，请大家指教

Date: 02/20/09   Time: 20:23    
Sample: 1978 2007    
Exogenous variables: None    
Automatic selection of maximum lags    
Automatic selection of lags based on SIC: 0 to 3    
Newey-West bandwidth selection using Bartlett kernel    
    
   Cross- 
Method Statistic Prob.** sections Obs
Null: Unit root (assumes common unit root process)     
Levin, Lin & Chu t*  14.1955  1.0000  29  819
    
Null: Unit root (assumes individual unit root process)     
ADF - Fisher Chi-square  2.20611  1.0000  29  819
PP - Fisher Chi-square  0.71767  1.0000  29  841
    
** Probabilities for Fisher tests are computed using an asymptotic Chi    
        -square distribution. All other tests assume asymptotic normality.