stata中对SVAR设置限制后显示rank不足怎么解决

经管之家Stata培训，陈强老师主讲，六天掌握高级计量与Stata多维度应用，报名咨询：010-68478566 我的代码是：matrix A = (1,.,0,0,.,0,0\0,1,0,0,0,0,0\.,.,1,.,0,.,0\.,.,0,1,.,0,0\.,.,0,0,1,0,0\.,.,0,.,.,1,0\.,.,.,.,.,.,1) matrix B = (.,0,0,0,0,0,0\0,.,0,0,0,0,0\0,0,.,0,0,0,0\0,0,0,.,0,0,0\0,0,0,0,.,0,0\0,0,0,0,0,.,0\0,0,0,0,0,0,.) svar dluc dlui dlur dlcc dlcnm dlci dlrer,aeq(A) beq(B) lags(1/3) var 结果显示为：These constraints place 70 independent constraints on A and B The order condition requires at least 70 constraints. Identification requires a rank of 98, but the identification matrix only has rank 97 求问这是为什么，要怎么解决 急求！！