如何在观星台中忽略操纵变量？

Question

我想在观星者中省略操纵变量。这里的受控变量表示我的数据集中没有这些变量，例如，我引入了平方项。 下面是我的代码。如何省略log（fall_t）和log（fall_t）^ 2之类的变量。我的数据集中确实有fall_t。

runmtw2_cp_oz11 <- plm(formula = lnyield ~ log(fall_t) + I(log(fall_t)^2) + 
                                 winter_t + wintertsq + 
                                 log(spring_t) + I(log(spring_t)^2) +
                                 log(fall_p) + I(log(fall_p)^2) + 
                                 log(winter_p) + I(log(winter_p)^2) + 
                                 log(spring_p) + I(log(spring_p)^2) + 
                                 ltt + qtt, 
                      data = dfto, effect = c("individual"), 
                      model = c("within"))


stargazer(runmtw2_cp_oz11, runmtw2_cp_oz6, runmtw2_cp_oz8, runmtw2_cp_oz10, 
          title = "Panel data with time trend",
          model.names = F, model.numbers = F,
          dep.var.caption = "Yield", dep.var.labels.include = F,
          notes = "*Average and square temperature of Winter are not in log form
          due to negative values.",
          align = T, no.space = T, column.sep.width = "1pt", omit.stat = "f")