求助！
    在用SPSS做conjoint analysis（联合分析）时，程序文件无法正常运行，总是跳出以下界面：

Warnings
SEQUENCE, RANK, OR SCORES SUBCOMMAND -- Too few variables are specified. There should be exactly as many variables as regular cards plus holdouts on plan file.
This command is not executed.

    那位同学能帮忙看看到底是为什么啊？万分感谢！