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 found a positive correlation between the frequency of occurrence of letters and phonemes and how attractive they were judged to be. Zajonc extended these studies, using foreign symbols and controlling the number of exposures. This led him to formulate the mere-exposure hypothesis: the more you see something, the more you like it. Nuttin's original study showed that mere exposure can not be the cause of the name-letter effect, as letters with equal frequency were evaluated differently by people who had the letter in their names and those who did not. He also found that whereas the letter B is of