_E_x_t_r_a_c_t _M_o_d_e_l _R_e_s_i_d_u_a_l_s
	
	     residuals(x, ...)
	     resid(x, ...)
	
	_A_r_g_u_m_e_n_t_s:
	
	           x : an object for which the extraction of model
	               residuals is meaningful.
	
	         ... : other arguments.
	
	_D_e_s_c_r_i_p_t_i_o_n:
	
	     residuals is a generic function which extracts model
	     residuals from objects returned by modeling functions.
	     The abbreviated form resid is intended to encourage
	     users to access object components through an accessor
	     function rather than by directly referencing an object
	     slot.
	
	     All object classes which are returned by model fitting
	     functions should provide a residuals method.
	
	_S_e_e _A_l_s_o:
	
	     coefficients, fitted.values, glm, lm.