Reinitializes data to original inputs, and drops any estimated
		results.

def reset(self):

		"""
		Reinitializes data to original inputs, and drops any estimated
		results.
		"""

		Y, D, X = self.old_data['Y'], self.old_data['D'], self.old_data['X']
		self.raw_data = Data(Y, D, X)
		self.summary_stats = Summary(self.raw_data)
		self.propensity = None
		self.cutoff = None
		self.blocks = None
		self.strata = None
		self.estimates = Estimators()