Each relation gets its own weight matrix and its own normalisation constant, the paper's default being the per-relation neighbour count. A relation with no neighbours for a node contributes nothing rather than dividing by zero.
References
Schlichtkrull, Kipf, Bloem, van den Berg, Titov and Welling (2018), Modeling relational data with graph convolutional networks, ESWC 2018, eq. (2). arXiv:1703.06103
Examples
Kgnn(A_r = c(1, 2, 3, 4, 5, 6, 7, 8), X = 5L, W_r = c(1, 2, 3, 4, 5, 6, 7, 8))
#> $estimate
#> [1] 185
#>
#> $H
#> [,1]
#> [1,] 185
#>
#> $n
#> [1] 1
#>
#> $relations
#> [1] 8
#>
#> $method
#> [1] "h' = relu(sum_r sum_j W_r h_j / |N_i^r| + W_0 h_i), Schlichtkrull et al. (2018) eq. (2)"
#>
#> attr(,"class")
#> [1] "morie_rich_result" "list"
