Chapter 7.2 - 1st Layer Normalization
Residual Output
=
[
[1.133, -0.299, 0.503],
[-0.176, 0.911, 0.143],
[0.766, 0.781,-0.518],
[1.601, -0.669,0.368],
[0.663, 0.779,0.648]
]
we calculate mean row by row (showing first row eg.)
mean = (1.133 - 0.299 + 0.503) / 3 ≈ 0.446
Calculate standard daviation
1.133 - 0.446, = 0.687, -0.299 - 0.446, = -0.745, 0.503 - 0.446 = 0.057
so final top row
[ 0.687, -0.745, 0.057 ]
calculate squares
variance = average((x - mean)²) [ 0.687², (-0.745)², 0.057² ] = [ 0.472, 0.555, 0.003 ]
Calculate average
variance = (0.472 + 0.555 + 0.003)/3
variance = 0.343
Add epsilon
variance + ε ≈ 0.343
Calculate standard daviation
standard daviation = √(variance + ε ) = √0.343 ≈ 0.586
Divide by standard deviation
[ 0.687 / 0.586, -0.745 / 0.586, 0.057 / 0.586 ] =[ 1.17, -1.27, 0.10 ]
Apply gamma and beta (optional)
LayerNorm = γ × normalized + β
values example :
γ = [1,1,1]
β = [0,0,0]
final result top row :
LayerNorm Output
= [ 1.17, -1.27, 0.10 ]
after doing with every row we get :
LayerNorm Output =
[
[ 1.40,-1.52, 0.12],
[-1.15, 1.29,-0.14],
[ 0.71, 0.70,-1.41],
[ 1.31,-1.14,-0.17],
[-0.16, 0.91,-0.75]
]