我做的面板数据结果如下，怎么没有R值d.w和F值呢?刚刚自学的面板数据，不知道这个现象是不是正常的？请各位高手帮忙解决！

Dependent Variable: LRG-LRG(-1)
Method: Panel Generalized Method of Moments
Transformation: First Differences
Date: 12/23/06 Time: 20:31
Sample (adjusted): 2000 2005
Cross-sections included: 5
Total panel (balanced) observations: 30
Difference specification instrument weighting matrix
White period standard errors & covariance (d.f. corrected)
Instrument list: @DYN(LRG-LRG(-1),-2) LRG(-1) LTO LBC
@LEV(@SYSPER)

Variable Coefficient Std. Error t-Statistic Prob.

LRG(-1) -0.205708 0.225462 -0.912383 0.3719
LTO -0.000482 0.007586 -0.063499 0.9500
LBC -0.035096 0.009484 -3.700363 0.0013
@LEV(@ISPERIOD("2000")) 0.003299 0.012551 0.262811 0.7953
@LEV(@ISPERIOD("2001")) 0.025578 0.017914 1.427809 0.1680
@LEV(@ISPERIOD("2002")) 0.025294 0.019233 1.315126 0.2026
@LEV(@ISPERIOD("2003")) 0.021576 0.019111 1.128948 0.2717
@LEV(@ISPERIOD("2004")) 0.036310 0.018602 1.951966 0.0644
@LEV(@ISPERIOD("2005")) 0.023407 0.026497 0.883370 0.3870

Effects Specification

Cross-section fixed (first differences)
Period fixed (dummy variables)

Mean dependent var 0.007051 S.D. dependent var 0.014366
S.E. of regression 0.012334 Sum squared resid 0.003195
J-statistic 15.61771 Instrument rank 23.00000