#offsets

d2l labels the offset of an anchor $A$ (centre $(x_a, y_a)$, size $w_a \times h_a$) towards its ground-truth box $B$ (centre $(x_b, y_b)$, size $w_b \times h_b$) as $\left(\frac{(x_b - x_a)/w_a}{\sigma_x}, \frac{(y_b - y_a)/h_a}{\sigma_y}, \frac{\log(w_b/w_a)}{\sigma_w}, \frac{\log(h_b/h_a)}{\sigma_h}\right)$ with $\sigma_x = \sigma_y = 0.1$ and $\sigma_w = \sigma_h = 0.2$. The anchor has centre $(100, 100)$ and size $50 \times 100$; the ground truth has centre $(110, 90)$ and size $60 \times 80$ (width × height).

The $x$ offset is and the width offset is .