Matrix for MRQAP/network regression

[MilaB]

Hey everyone!
I have data on the sex of the respondents with 1=male 2=female.

To performe MRQAP I need a relational matrix as independent variable where 1=same gender 0=different gender.
How can I generate a matrix like this from my initial data on sex?

Thanks for your help!

[AlexisW]

For those of us not familiar with MRQAP it would help to provide an example of what you're trying to achieve.

If I understand correctly, you have a vector like this:

respondents <- sample(c(1, 2), size = 6, replace = TRUE)
respondents
#> [1] 2 1 2 1 1 1

And you want to make a matrix by comparing the vector to itself. You can do that with outer(), telling it that the operation you are doing to compare these vectors is equality ==

outer(respondents, respondents, "==")
#>       [,1]  [,2]  [,3]  [,4]  [,5]  [,6]
#> [1,]  TRUE FALSE  TRUE FALSE FALSE FALSE
#> [2,] FALSE  TRUE FALSE  TRUE  TRUE  TRUE
#> [3,]  TRUE FALSE  TRUE FALSE FALSE FALSE
#> [4,] FALSE  TRUE FALSE  TRUE  TRUE  TRUE
#> [5,] FALSE  TRUE FALSE  TRUE  TRUE  TRUE
#> [6,] FALSE  TRUE FALSE  TRUE  TRUE  TRUE

Or if you want it with 0 and 1 instead of TRUE/FALSE:

1L * outer(respondents, respondents, "==")
#>      [,1] [,2] [,3] [,4] [,5] [,6]
#> [1,]    1    0    1    0    0    0
#> [2,]    0    1    0    1    1    1
#> [3,]    1    0    1    0    0    0
#> [4,]    0    1    0    1    1    1
#> [5,]    0    1    0    1    1    1
#> [6,]    0    1    0    1    1    1

^{Created on 2022-11-10 by the reprex package (v2.0.1)}