Crosstab for contrasts

[Andrzej]

Hi, I try to grasp a concept of contrasts (planned comparisons) in R.
I need to create such a table:

This simple table will illustrate what could be compared with what, and how many comparisons do we have to do ?

Here is my data:

dat <- structure(list(ID = c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,
29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44,
45, 46, 47, 48), Self_control = c(65, 70, 60, 60, 60, 55, 60,
55, 70, 65, 60, 70, 65, 60, 60, 50, 55, 65, 70, 55, 55, 60, 50,
50, 50, 55, 80, 65, 70, 75, 75, 65, 45, 60, 85, 65, 70, 70, 80,
60, 30, 30, 30, 55, 35, 20, 45, 40), Sex = structure(c(1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L,
2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L), levels = c("Female",
"Male"), class = "factor"), Alcohol = structure(c(1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L,
3L, 3L, 3L, 3L, 3L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L,
2L, 2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), levels = c("None",
"2 Pints", "4 Pints"), class = "factor")), row.names = c(NA,
48L), class = "data.frame")


# Factor:
dat$Sex <- factor(dat$Sex, levels=c("Male", "Female"),
                  labels=c("Male", "Female"))

dat$Sex <- relevel(dat$Sex, ref="Female")

levels(dat$Sex)

Obviously when I use:

contrasts(dat$Alcohol) 

contr.treatment(levels(dat$Alcohol))

It gives me:

but it looks rather cryptic. So I have figured that my table will be better to understand what is going on for a starting point.

How do I create such a table ? How do I start, please ? Any help will be much appreciated.
Maybe a ready function exists in R to do it ?

kind regards,

[nirgrahamuk]

maybe :

alc <- c("None", "2 Pints", "4 Pints")
alcohol <- factor(alc,levels=alc)
(a1 <- contrasts(alcohol))
a2 <- cbind(1-rowSums(a1),a1)
colnames(a2)<- rownames(a2)
a2

giving

        None 2 Pints 4 Pints
None       1       0       0
2 Pints    0       1       0
4 Pints    0       0       1

[Andrzej]

Thank you for kind reply.
What does it show us ? This is different from my desired result.

[nirgrahamuk]

Do you further want to change 1 and 0 to mathematical symbols + and × ?

[Andrzej]

Yes, I do, if possible, or other symbols just to indicate possible comparisons.

[nirgrahamuk]

alc <- c("None", "2 Pints", "4 Pints")
alcohol <- factor(alc,levels=alc)
(a1 <- contrasts(alcohol))
a2 <- cbind(1-rowSums(a1),a1)
colnames(a2)<- rownames(a2)
a2
library(tidyverse)
(a3 <- as.data.frame(a2) |> mutate_all(
  \(x)case_match(
    x,
    0~'+',
    1~'x'
  )
))

        None 2 Pints 4 Pints
None       x       +       +
2 Pints    +       x       +
4 Pints    +       +       x

[Andrzej]

Is it possible somehow to add rows and columns totals summing pluses up ?

[nirgrahamuk]

(a4 <- rownames_to_column(a3,var = " "))
(a5 <- bind_rows(
  a4,
  a4 |> summarise(across(rownames(a3),
    .fns = \(x_)as.character(sum(x_ == "+"))),
    across(" ", \(x_)"Total")
  ))
)

          None 2 Pints 4 Pints
1    None    x       +       +
2 2 Pints    +       x       +
3 4 Pints    +       +       x
4   Total    2       2       2

[Andrzej]

Thank you very much indeed for your kind help. There is no rows total column but I assume that it would be difficult to achieve.
The final table looks very nice and will be useful for me.

[nirgrahamuk]

(a4 <- rownames_to_column(a3,var = " "))
(a5 <- bind_rows(
  a4 |>  rowwise() |> mutate("Total"= sum(c_across(-" ")=='+')),
  a4 |> summarise(across(rownames(a3),
                         .fns = \(x_)as.character(sum(x_ == "+"))),
                  across(" ", \(x_)"Total")) |> 
    rowwise() |> mutate("Total"= sum(as.numeric(c_across(-" "))))
  ) |> tibble()
)

# A tibble: 4 × 5
  ` `     None  `2 Pints` `4 Pints` Total
  <chr>   <chr> <chr>     <chr>     <dbl>
1 None    x     +         +             2
2 2 Pints +     x         +             2
3 4 Pints +     +         x             2
4 Total   2     2         2             6

[Andrzej]

I would like to thank you unreservedly, be blessed, safe and healthy - always.