如何使用“_xgb.Booster”"model_fit" 由防风草函数 boost_tree 渲染的对象来计算提升曲线和等分提升图?

How can I calculate lift curves and decile lift charts using "_xgb.Booster" "model_fit" objects rendered from parsnip function boost_tree?

我有这段代码呈现“_xgb.Booster”“model_fit”对象类。我应该,但我不确定如何在此处提供带有数据的完整可重现示例代码!

xgb <- boost_tree(mode = "classification",

                      trees = 100,
                      mtry = 0.7,
                      learn_rate = 0.15,
                      tree_depth = 10,
                      sample_size = 1) %>%
      set_engine("xgboost") %>%
      fit(Y ~ ., data = train)

如何使用此 xgb 对象计算提升曲线和等分提升图?

一旦您的数据采用示例数据集 two_class_example 中的形式,您就可以使用 lift_curve() 函数来计算它。然后就可以用提升曲线做可视化了。

library(tidymodels)

two_class_lift <- two_class_example %>%
  lift_curve(truth, Class1) 

two_class_lift %>%
  autoplot()


two_class_lift %>%
  group_by(.percent_tested = cut_interval(.percent_tested, n = 10)) %>%
  summarise(.lift = mean(.lift, na.rm = TRUE)) %>%
  ggplot(aes(.percent_tested, .lift)) +
  geom_col() +
  theme_bw() +
  labs(x = "% Tested", y = "Lift")
#> `summarise()` ungrouping output (override with `.groups` argument)

reprex package (v0.3.0.9001)

于 2020-08-26 创建

如果您需要帮助从您的 xgboost 模型中获得预测,check out this article at tidymodels.org