r - geom_smooth 中二项式公式的语法

Question

我在 R 中计算了二项式回归:

Call:
glm(formula = cbind(success, failure) ~ x * f, family = "binomial", 
    data = tb1)

Deviance Residuals: 
    Min       1Q   Median       3Q      Max  
-3.6195  -0.9399  -0.0493   0.5698   2.0677  

Coefficients:
              Estimate Std. Error z value Pr(>|z|)    
(Intercept) -2.3170182  0.0622600 -37.215  < 2e-16 ***
x            0.0138201  0.0009892  13.972  < 2e-16 ***
fTRUE        0.6466238  0.1976115   3.272  0.00107 ** 
x:fTRUE     -0.0035741  0.0032587  -1.097  0.27273    
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1

(Dispersion parameter for binomial family taken to be 1)

    Null deviance: 479.88  on 147  degrees of freedom
Residual deviance: 201.53  on 144  degrees of freedom
  (7 observations deleted due to missingness)
AIC: 870.72

Number of Fisher Scoring iterations: 4    

我想把它形象化。我想绘制数据和回归曲线。我可以轻松地使线性更平滑:

ggplot(tb1, aes(x, success/(success+failure), colour=f)) +
  geom_point() +
  geom_smooth(method="lm")

但我真正想要的是通过数据绘制逻辑曲线。当我尝试:

ggplot(tb1, aes(x, success/(success+failure), colour=f)) +
  geom_point() +
  geom_smooth(
    method="glm",
    method.args=list(family="binomial"),
  )

我得到这个图:



这似乎不对。标准误差不应该那么大。我想我需要在 geom_smooth 中明确指定公式，但我无法正确使用语法。当我尝试

ggplot(tb1, aes(x, success/(success+failure), colour=f)) +
  geom_point() +
  geom_smooth(
    method="glm",
    method.args=list(
      family="binomial",
      formula = cbind(success, failure) ~ x
    )
  )

我得到

Warning message:
Computation failed in stat_smooth():
object 'success' not found

如何正确指定公式？

Answer 1

与二项式回归一样，geom_smooth 中的公式需要有一个成功和失败的矩阵作为响应。需要在美学中定义相应的变量:

ggplot(tb1, aes(x, y=success/(success+failure), colour=f, succ=success, fail=failure)) +
  geom_point() +
  geom_smooth(
    method="glm",
    method.args=list(family="binomial"),
    formula = cbind(succ, fail) ~ x
  )

现在它的工作原理:



感谢 NelsonGon指出这一点。