proc model data=ipo.fna1; parms b0-b29; retnfstd=b0+b1*age+b2*lnamnt+b3*shrcntr+b4*bj+b5*gg+b6*indcd1+b7*indcd2+b8*indcd3 +b9*indcd4+b10*indcd5+b11*yr90+b12*yr91+b13*yr92+b14*yr93+b15*yr94+b16*yr95+b17*yr96 +b18*yr97+b19*yr98+b20*yr99+b21*yr00+b22*yr02+b23*yr02+b24*yr03+b25*yr04+b26*yr05+b27*yr06 +b28*yr07+b29*yr08; fit retnfstd/gmm kernel=(bart,1,0); run; 这是关于回归的一段程序,indcd1-indcd5是行业虚拟变量,yr90-yr99 及yr00-yr08是年份虚拟变量。 但log 显示如下错误: ERROR: The number of parameters (31) is greater than the number of unique instruments (30) times the number of equations (1). 请问是哪里出问题了? |