A location engine is disclosed that estimates the location of a wireless terminal using (i) cell ID, (ii) triangulation, (iii) GPS, (iv) RF pattern-matching, or (v) any combination of them. The location engine is adept at discounting the contribution of apparently reasonable but erroneous data. The location engine receives data that are evidence of the location of a wireless terminal at each of a plurality of different times. The location engine then generates an initial hypothesis for the location of the wireless terminal at each time assuming that all of the data is correct and equally probative. Next, the location engine generates one alternative hypothesis for each initial hypothesis and each datum assuming that the datum is erroneous. Finally, the location engine generates the estimate for the location of the wireless terminal at each time by determining which combination of initial hypotheses and alternative hypothesis is the most self-consistent.