A three-magnet assembly configured for use in a position sensing system is disclosed. In an example, the three-magnet assembly establishes a non-linear spatially varying magnetic field configured to be measured by a magnetic field measurement device so that resolvable measurements are spatially distributed in a non-linear fashion. The resolvable measurements are distributed to a relatively higher concentration in at least one first region along a measurement stroke and to a relatively lower concentration in at least one second region along a measurement stroke, the second region being different from the first region. In an example, the different concentrations of resolvable measurements are utilized to spatially vary the precision of a position sensor along a measurement stroke. A system and methods for correlating magnetic field measurements to expected positions are also disclosed.