黃河泉 发表于 2017-4-21 08:05 
跟我猜的一样,你的 idstd 每个观察值都不一样,不可以用 areg。就正常的回归即可!
但是我用正常回归就会这样:
. xi:reg lnsales lnraildensity lnlabor_cost lncapital lnmaterials lnage i.idstd,r
i.idstd _Iidstd_522001-524848(naturally coded; _Iidstd_522001 omitted)
matsize too small
You have attempted to create a matrix with too many rows or columns or attempted to fit a model with too many variables. You need to increase matsize; it is currently 400.
Use set matsize; see help matsize.
If you are using factor variables and included an interaction that has lots of missing cells, either increase matsize or set emptycells drop to reduce the required matrix
size; see help set emptycells.
If you are using factor variables, you might have accidentally treated a continuous variable as a categorical, resulting in lots of categories. Use the c. operator on such
variables.
r(908);
这要怎么办啊...
谢谢!