One Van, Two Rectangles

A detector is evaluated on a single delivery van. Every box is written as $(x_1, y_1, x_2, y_2)$ — the top-left and the bottom-right corner, in pixels.

The ground-truth box is

$G = (10,\ 10,\ 50,\ 40)$

Two detectors each return one box for that van:

box	corners	how it was drawn
$A$	$(0,\ 0,\ 60,\ 50)$	generously — it contains the whole van with room to spare
$B$	$(22,\ 10,\ 50,\ 40)$	cautiously — it sits entirely inside the van, clipping one end

Each box is scored against $G$ by IoU, and a detection counts as correct when its IoU reaches the threshold in use.

Which statement describes the verdicts at a threshold of $0.5$ , and then at a threshold of $0.75$ ?

One Van, Two Rectangles

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