Eye chart number). The denominator indicates the distance in feet at which a person with normal vision could stand to correctly identify the same symbols identified by the person tested. For example, a visual acuity of 20/20 is considered normal. Numerous types of eye charts exist and are used in various situations. For example, the Snellen chart is designed for use at 6 meters or 20 feet, and is thus appropriate for testing distance vision. There is often also a need to test a subject's vision at near or occupational tasks (such as reading or computer use). For these situations, a Rosenbaum
Name-letter effect counts of any letter, which also caused Nuttin to cast doubt on whether Zajonc's theory could hold true in the real world. Subjective frequency is how frequently subjects a stimulus appears. Name letters may be noticed more and, consequently, assumed to occur more frequently than other letters. Early research into the impact of exposure showed that differences in subjective frequency yielded different results even when the frequency was identical. Hoorens and Nuttin tested whether subjective frequency could be an explanation for the name-letter effect by asking subjects to rank-order the entire alphabet twice, once according to their letter preference and