Error: inadequate matsize; must be at least 461
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, try 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);

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我的数据是非平衡长面板，在做组间同期相关检验时出现这个结果