The negative binomial unit deviance
\(2\{y \log(y/\mu) - (y + 1/\phi) \log((y + 1/\phi)/(\mu + 1/\phi))\}\),
elementwise over a genes x cells matrix, on the CPU or – when y
or mu is a torch tensor – on that tensor's device.
Examples
y <- matrix(rpois(20, 3), 4, 5)
nbUnitDeviance(y, mu = y + 0.5, phi = 0.1)
#> [,1] [,2] [,3] [,4] [,5]
#> [1,] 0.04029267 0.03059289 0.04029267 0.08715366 0.97580328
#> [2,] 0.02418059 0.04029267 0.16700856 0.08715366 0.05634445
#> [3,] 0.04029267 0.03059289 0.04029267 0.02418059 0.97580328
#> [4,] 0.04029267 0.05634445 0.16700856 0.01967605 0.05634445