  Characterization of microlensing planets requires modeling of observed light
curves including many parameters. Studying the dependency of the pattern of
light curves on the lensing parameters and the correlations between the
parameters is important to understand how the uncertainties of the planetary
parameters are propagated from other parameters. In this paper, we show that
despite the apparent complexity of the pattern of light curves of planetary
lensing events, the correlations between the lensing parameters can be
understood by studying how the parameters affect the characteristics of lensing
light curves such as the height and width, the caustic-crossing time scale, and
the location and duration of planetary perturbations. Based on analytic
arguments about the dependency of light curve features on the parameters, we
obtain the correlations for the two representative cases of planetary events.
We also demonstrate the applicability of the correlations to general planetary
events by actually obtaining the correlations from modelings of light curves
produced by simulations.
