使用skimr创建汇总统计数据框架

Question

我最近遇到了一个名为skimr的包，它有助于创建有用的汇总统计信息。我编写了以下代码，以便仅在数字列上提取汇总统计信息。我的第一个问题是，skimr有没有一种更直接的方式来指定我想要汇总统计信息的变量类型？我的第二个问题是，当我编写my_skim“闭包”时，append == TRUE实际上实现了什么？

library(skimr)
library(dplyr)

### Creating an example dataset 

test.df1 <- data.frame("Year" = sample(2018:2020, 20, replace = TRUE), 
                       "Firm" = head(LETTERS, 5), 
                       "Exporter"= sample(c("Yes", "No"), 20, replace = TRUE), 
                       "Revenue" = sample(100:200, 20, replace = TRUE),
                         stringsAsFactors =  FALSE)

test.df1 <- rbind(test.df1, 
                    data.frame("Year" = c(2018, 2018),
                               "Firm" = c("Y", "Z"),
                               "Exporter" = c("Yes", "No"),
                               "Revenue" = c(NA, NA)))

test.df1 <- test.df1 %>% mutate(Profit = Revenue - sample(20:30, 22, replace = TRUE ))

### Using skimr package to extract summary stats

my_skim <- skim_with(numeric = sfl(minimum = min, maximum = max, hist = NULL), append = TRUE)

test.df1_skim1 <- test.df1 %>% 
 group_by(Year) %>% 
  my_skim() %>% 
   filter (skim_type != "character") %>% 
    select(-starts_with("character"))

Answer 1

如果您只需要数字变量的摘要，则可以将所有其他类型设置为NULL，或者可以运行skim并使用yank()获取某个类型的子表。来自https://docs.ropensci.org/skimr/articles/skimr.html#reshaping-the-results-from-skim-

  skim(Orange) %>% yank("numeric")

append选项允许您替换默认统计信息或附加到默认值。