When visual search dominates, time rises linearly with option count

What it is

When people do not know target location and must look through an interface, visual search can dominate time. For items requiring serial inspection, search time often increases roughly linearly with count. Hick's logarithmic relation concerns response selection among known alternatives and cannot replace a search model.

Why it happens

Visual search allocates attention, reads locations or features, and rules out candidates when a target is not salient. Each extra item can require another fixation or comparison. A unique colour, shape, or location can produce feature pop-out and weaken count dependence; searchability, not count alone, is decisive.

Studying it

Vary item count, target salience, layout rule, and whether the target is announced. Measure first fixation, location time, accuracy, and gaze path. Separate time to find from subsequent choice and pointing. Include target-absent trials to determine whether people actually searched the set.

Where it stops holding

Fixed locations, strong categories, search boxes, and learned memory lower visual-search cost; in complex lists, even few options can be slow through similarity or unreadable text. A linear trend is not guaranteed; test concrete features and layout.

Related

• Same group: B1.13.1 With unequal alternatives, decision time depends on information distribution, not count · B1.13.3 The law covers choice among known options, not time to understand them · B1.13.4 Fewer visible options can split one choice into layers without lowering total time · B1.13.5 Semantic similarity makes the law underestimate real decision time
• Nearby: B1.04 Hick-Hyman law · B1.06 Memory-scanning law
• Search terms: visual search · serial search · set-size effect