Eddington's bias

Eddington's bias occurs in observational astronomy when measurement errors cause more faint objects to be mistakenly counted as brighter (and thus more detectable) than brighter objects are to be counted as fainter. Because there are more faint objects than bright ones, this bias leads to an overestimation of the number of objects at higher brightness levels. Essentially, measurement uncertainties combined with the uneven distribution of objects can skew the observed data, making the population appear brighter or more abundant than it truly is. Proper statistical correction is needed to account for this bias and obtain accurate results.