In each experiment … the experimenters either created their own icons, used … [The icons were median split into] arbitrary functions … (e.g., a semicircular arrow … to represent undo … ) … Representational functions … (e.g., a picture of a printer denoting print) … [and median split into] Graphically abstract … (e.g., an outline of a printer) … Graphically concrete … ( … e.g., a detailed picture of a printer).
Google-1
Google-2
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