An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A systematic error that can be introduced when → trigonometric parallaxes are used to calibrate a luminosity system. The bias arises when stars are selected by a lower limit in the observed parallax values. This favors the stars for which the measured parallax result is relatively too large.

Named after Th. Lutz & D.H. E. Kelker, 1973, PASP 85, 573; → bias.