Two manufacturing facilities produce 1280 × 1024 LED (light-emitting diode) displays. Twelve displays are chosen at random from each lab, and the number of bad pixels is noted for each display.
Research question: At α = .05, do the medians differ?
Defects in Randomly Inspected LED Displays
Facility Number of Bad Pixels
Lab A 2 0 5 0 1 2 0 5 0 4 1 2
Lab B 0 1 2 3 1 0 0 1 2 2 1 0