当使用负二项模型时，我如何在R中绘制交互？

library(MASS)
library(ggplot2)

# 示例数据集
data <- data.frame(x = 1:10, y = c(5, 10, 15, 20, 25, 30, 35, 40, 45, 50))

# 使用负二项模型拟合数据
fit <- glm.nb(y ~ x, data = data)

# 创建一个新数据框来存储预测值
newdata <- data.frame(x = seq(1, 10, 0.1))

# 预测拟合的值
newdata$y_pred <- predict(fit, newdata = newdata, type = "response")

# 绘制原始数据散点图和拟合曲线
ggplot(data, aes(x = x, y = y)) +
  geom_point() +
  geom_line(data = newdata, aes(x = x, y = y_pred), color = "red") +
  labs(x = "x", y = "y")