A method for characterizing a yarn moved along its longitudinal direction. Readings of a characteristic of the yarn along the longitudinal direction of the yarn are detected. Values of a yarn parameter are determined from the readings. An event field is provided, which contains a quadrant of a two-dimensional Cartesian coordinate system, whose abscissa defines an extension of yarn parameter values in the longitudinal direction and whose ordinate defines a deviation of the yarn parameter from a desired value. Densities of events in the event field are determined from the values of the yarn parameter and their extensions in the longitudinal direction. A yarn body is represented as an area in the event field. The area on the one hand is delimited by the abscissa, on the other hand by the ordinate and further by a line in the event field that substantially follows a constant event density. The representation of the yarn body permits a clearing limit to be defined in a rapid and rational manner.