Called by Strata class during initialization.

def _summarize_pscore(self, pscore_c, pscore_t):

		"""
		Called by Strata class during initialization.
		"""

		self._dict['p_min'] = min(pscore_c.min(), pscore_t.min())
		self._dict['p_max'] = max(pscore_c.max(), pscore_t.max())
		self._dict['p_c_mean'] = pscore_c.mean()
		self._dict['p_t_mean'] = pscore_t.mean()