我正在尝试对具有许多因素的负二项式模型进行逐步分析:
step(glm.nb(totphy~lat+long+elev+cult+poll+blkage+canden+irr+dust+dustcon+mid+herb+miteprob+ermprob+tsmprob+mcdprob+brprob+armprob+mitapp+acra+agri+carz+envi+fujim+next+vend+zeal+cover+orchtype+pestint+mating+ties+rimon+igr+lime+naa+sevin+land+area+ermpres+tsmpres+mcdpres+armpres+zmalipres+ltemp+lmaxtemp+lmintemp+ldewp+lrh+lwindsp+lwinddir+lsolar+lprecip+lleaf+lsoil,data=mites), direction="forward", criterion=aic)
如果我只包含最多“fujim”的变量,则此代码有效,添加更多变量会导致此错误:
Error in eval(expr, envir, enclos) :
no loop for break/next, jumping to top level
我对R相当不熟悉,那么这是什么意思?