按组获取标准偏差并从 R 中的平均列标准偏差中减去
Get a standard deviation by group and subtract from mean column standard deviation in R
我有一个玩具 df 包含在下面。对于 Grades 和 Age 列，我需要通过 University[ 找出平均标准差与总标准差之间的差异=32=]。新的 table 中的值 - 应该有 4 行和 2 列 - 因此应该代表 Grades 和 Age[= 的标准差差异每个 University 中的 32=] 与 Grades 和 Ages 的总 df 标准偏差（在所有大学）。
数据：
library(dplyr)
df <- tibble::tribble(
~University, ~Countries, ~Grades, ~Age,
"University-1", "USA", 46, 29,
"University-1", "UK", 84, 30,
"University-1", "Sweden", 5, 28,
"University-1", "Spain", 40, 26,
"University-1", "Portugal", 49, 29,
"University-1", "Italy", 16, 24,
"University-1", "USA", 34, 19,
"University-1", "UK", 66, 28,
"University-1", "Sweden", 9, 25,
"University-1", "Spain", 80, 20,
"University-1", "Portugal", 55, 20,
"University-1", "Italy", 4, 21,
"University-1", "USA", 93, 18,
"University-1", "UK", 62, 28,
"University-1", "Sweden", 80, 30,
"University-2", "Spain", 1, 22,
"University-2", "Portugal", 56, 25,
"University-2", "Italy", 9, 29,
"University-2", "USA", 40, 21,
"University-2", "UK", 54, 20,
"University-2", "Sweden", 60, 24,
"University-2", "Spain", 77, 21,
"University-2", "Portugal", 22, 18,
"University-2", "Italy", 53, 29,
"University-2", "USA", 11, 21,
"University-2", "UK", 65, 27,
"University-2", "Sweden", 24, 27,
"University-2", "Spain", 18, 23,
"University-2", "Portugal", 73, 19,
"University-2", "Italy", 79, 22,
"University-1", "USA", 2, 26,
"University-1", "UK", 83, 23,
"University-1", "Sweden", 5, 19,
"University-1", "Spain", 75, 19,
"University-1", "Portugal", 12, 21,
"University-1", "Italy", 68, 29,
"University-1", "USA", 100, 21,
"University-1", "UK", 49, 21,
"University-1", "Sweden", 81, 20,
"University-1", "Spain", 99, 23,
"University-1", "Portugal", 82, 24,
"University-1", "Italy", 23, 26,
"University-1", "USA", 86, 30,
"University-1", "UK", 50, 20,
"University-1", "Sweden", 4, 19,
"University-2", "Spain", 12, 25,
"University-2", "Portugal", 12, 21,
"University-2", "Italy", 45, 21,
"University-2", "USA", 16, 26,
"University-2", "UK", 56, 23,
"University-2", "Sweden", 63, 24,
"University-2", "Spain", 37, 28,
"University-2", "Portugal", 86, 21,
"University-2", "Italy", 95, 18,
"University-2", "USA", 56, 20,
"University-2", "UK", 27, 20,
"University-2", "Sweden", 3, 27,
"University-2", "Spain", 18, 27,
"University-3", "Portugal", 68, 27,
"University-3", "Italy", 48, 21,
"University-3", "Portugal", 86, 21,
"University-3", "Italy", 95, 18,
"University-3", "USA", 56, 20,
"University-3", "UK", 27, 20,
"University-3", "Sweden", 3, 27,
"University-3", "Spain", 18, 27,
"University-3", "Portugal", 68, 27,
"University-3", "Italy", 48, 21,
"University-4", "Portugal", 86, 21,
"University-4", "Italy", 95, 18,
"University-4", "USA", 56, 20,
"University-4", "UK", 27, 20,
"University-4", "Sweden", 3, 27,
"University-4", "Spain", 18, 27,
"University-4", "Portugal", 68, 27,
"University-4", "Italy", 48, 21
)
我对此的尝试：
df <- df %>%
mutate(grades_sd = sd(Grades),
age_sd = sd(Age)) %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - grades_sd,
Age_sd = sd(Age) - age_sd)
这段代码执行了正确的（我认为）计算，但以错误的格式输出了 table。我很感激任何关于这方面的指导。
编辑：包括下面的预期输出。
output <- tibble::tribble(
~University, ~Grades_sd, ~Age_sd,
"University-1", 2.666482, 0.40233934,
"University-2", -2.790652, -0.34945170,
"University-3", 0.881169, -0.03754330,
"University-4", 2.398070, 0.06701784)
由于每个组都有相同的记录，summarise 重复它们。取唯一值将 return 只有一个，并且每个组将有一个摘要行。
df %>%
mutate(grades_sd = sd(Grades),
age_sd = sd(Age)) %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - unique(grades_sd),
Age_sd = sd(Age) - unique(age_sd))
输出；
University Grades_sd Age_sd
<chr> <dbl> <dbl>
1 University-1 2.67 0.402
2 University-2 -2.79 -0.349
3 University-3 -0.881 -0.0375
4 University-4 2.40 0.0670
我们可以使用 df 的未分组版本。
library(dplyr)
df %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - sd(df$Grades),
Age_sd = sd(Age) - sd(df$Age))
#> # A tibble: 4 × 3
#> University Grades_sd Age_sd
#> <chr> <dbl> <dbl>
#> 1 University-1 2.67 0.402
#> 2 University-2 -2.79 -0.349
#> 3 University-3 -0.881 -0.0375
#> 4 University-4 2.40 0.0670
由 reprex package (v2.0.1)
创建于 2022-01-06
我有一个玩具 df 包含在下面。对于 Grades 和 Age 列，我需要通过 University[ 找出平均标准差与总标准差之间的差异=32=]。新的 table 中的值 - 应该有 4 行和 2 列 - 因此应该代表 Grades 和 Age[= 的标准差差异每个 University 中的 32=] 与 Grades 和 Ages 的总 df 标准偏差（在所有大学）。
数据：
library(dplyr)
df <- tibble::tribble(
~University, ~Countries, ~Grades, ~Age,
"University-1", "USA", 46, 29,
"University-1", "UK", 84, 30,
"University-1", "Sweden", 5, 28,
"University-1", "Spain", 40, 26,
"University-1", "Portugal", 49, 29,
"University-1", "Italy", 16, 24,
"University-1", "USA", 34, 19,
"University-1", "UK", 66, 28,
"University-1", "Sweden", 9, 25,
"University-1", "Spain", 80, 20,
"University-1", "Portugal", 55, 20,
"University-1", "Italy", 4, 21,
"University-1", "USA", 93, 18,
"University-1", "UK", 62, 28,
"University-1", "Sweden", 80, 30,
"University-2", "Spain", 1, 22,
"University-2", "Portugal", 56, 25,
"University-2", "Italy", 9, 29,
"University-2", "USA", 40, 21,
"University-2", "UK", 54, 20,
"University-2", "Sweden", 60, 24,
"University-2", "Spain", 77, 21,
"University-2", "Portugal", 22, 18,
"University-2", "Italy", 53, 29,
"University-2", "USA", 11, 21,
"University-2", "UK", 65, 27,
"University-2", "Sweden", 24, 27,
"University-2", "Spain", 18, 23,
"University-2", "Portugal", 73, 19,
"University-2", "Italy", 79, 22,
"University-1", "USA", 2, 26,
"University-1", "UK", 83, 23,
"University-1", "Sweden", 5, 19,
"University-1", "Spain", 75, 19,
"University-1", "Portugal", 12, 21,
"University-1", "Italy", 68, 29,
"University-1", "USA", 100, 21,
"University-1", "UK", 49, 21,
"University-1", "Sweden", 81, 20,
"University-1", "Spain", 99, 23,
"University-1", "Portugal", 82, 24,
"University-1", "Italy", 23, 26,
"University-1", "USA", 86, 30,
"University-1", "UK", 50, 20,
"University-1", "Sweden", 4, 19,
"University-2", "Spain", 12, 25,
"University-2", "Portugal", 12, 21,
"University-2", "Italy", 45, 21,
"University-2", "USA", 16, 26,
"University-2", "UK", 56, 23,
"University-2", "Sweden", 63, 24,
"University-2", "Spain", 37, 28,
"University-2", "Portugal", 86, 21,
"University-2", "Italy", 95, 18,
"University-2", "USA", 56, 20,
"University-2", "UK", 27, 20,
"University-2", "Sweden", 3, 27,
"University-2", "Spain", 18, 27,
"University-3", "Portugal", 68, 27,
"University-3", "Italy", 48, 21,
"University-3", "Portugal", 86, 21,
"University-3", "Italy", 95, 18,
"University-3", "USA", 56, 20,
"University-3", "UK", 27, 20,
"University-3", "Sweden", 3, 27,
"University-3", "Spain", 18, 27,
"University-3", "Portugal", 68, 27,
"University-3", "Italy", 48, 21,
"University-4", "Portugal", 86, 21,
"University-4", "Italy", 95, 18,
"University-4", "USA", 56, 20,
"University-4", "UK", 27, 20,
"University-4", "Sweden", 3, 27,
"University-4", "Spain", 18, 27,
"University-4", "Portugal", 68, 27,
"University-4", "Italy", 48, 21
)
我对此的尝试：
df <- df %>%
mutate(grades_sd = sd(Grades),
age_sd = sd(Age)) %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - grades_sd,
Age_sd = sd(Age) - age_sd)
这段代码执行了正确的（我认为）计算，但以错误的格式输出了 table。我很感激任何关于这方面的指导。
编辑：包括下面的预期输出。
output <- tibble::tribble(
~University, ~Grades_sd, ~Age_sd,
"University-1", 2.666482, 0.40233934,
"University-2", -2.790652, -0.34945170,
"University-3", 0.881169, -0.03754330,
"University-4", 2.398070, 0.06701784)
由于每个组都有相同的记录，summarise 重复它们。取唯一值将 return 只有一个，并且每个组将有一个摘要行。
df %>%
mutate(grades_sd = sd(Grades),
age_sd = sd(Age)) %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - unique(grades_sd),
Age_sd = sd(Age) - unique(age_sd))
输出；
University Grades_sd Age_sd
<chr> <dbl> <dbl>
1 University-1 2.67 0.402
2 University-2 -2.79 -0.349
3 University-3 -0.881 -0.0375
4 University-4 2.40 0.0670
我们可以使用 df 的未分组版本。
library(dplyr)
df %>%
group_by(University) %>%
summarise(Grades_sd = sd(Grades) - sd(df$Grades),
Age_sd = sd(Age) - sd(df$Age))
#> # A tibble: 4 × 3
#> University Grades_sd Age_sd
#> <chr> <dbl> <dbl>
#> 1 University-1 2.67 0.402
#> 2 University-2 -2.79 -0.349
#> 3 University-3 -0.881 -0.0375
#> 4 University-4 2.40 0.0670
由 reprex package (v2.0.1)
创建于 2022-01-06