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The Scott effect is a bias that affects surveys of distant galaxy clusters that are identified by finding their constituent galaxies. The presence of unusually bright galaxies increases the chances that a cluster is identified, leading to a bias toward finding clusters with bright galaxies. Without compensating for this, it will appear that distant clusters have brighter galaxies or more bright galaxies than nearby ones. This is a lot like the Malmquist bias, but this effect relates to two levels of a hierarchy of objects: galaxies and clusters.