An example apparatus includes interface circuitry, machine-readable instructions, and at least one processor circuit to be programmed by the machine-readable instructions to access a first saliency map and a second saliency map associated with an image dataset, encode pixel-level intensity of the first saliency map, encode pixel-level intensity of the second saliency map, generate a saliency comparison metric based on the pixel-level intensity of the first saliency map and the pixel-level intensity of the second saliency map, and compare spatial properties of the first saliency map and the second saliency map using the saliency comparison metric.