eigenw                 package:spdep                 R Documentation

_S_p_a_t_i_a_l _w_e_i_g_h_t_s _m_a_t_r_i_x _e_i_g_e_n_v_a_l_u_e_s

_D_e_s_c_r_i_p_t_i_o_n:

     The function returns a numeric vector of eigenvalues of the
     weights matrix generated from the spatial weights object 'listw'.
     The eigenvalues are  used to speed the computation of the Jacobian
     in spatial SAR model estimation:


      log(det[I - rho W]) = logprod_{i=1}^{n}(1 - rho lambda_i)


     where W is the n by n spatial weights matrix, and lambda[i] are
     the eigenvalues of W.

_U_s_a_g_e:

     eigenw(listw, quiet=TRUE)

_A_r_g_u_m_e_n_t_s:

   listw: a 'listw' object created for example by 'nb2listw'

   quiet: set to FALSE for short summary

_V_a_l_u_e:

     a numeric vector of eigenvalues of the weights matrix generated
     from the spatial weights object 'listw'.

_A_u_t_h_o_r(_s):

     Roger Bivand Roger.Bivand@nhh.no

_R_e_f_e_r_e_n_c_e_s:

     Cliff, A. D., Ord, J. K. 1981 Spatial processes, Pion, p. 155;
     Ord, J. K. 1975 Estimation methods for models of spatial
     interaction, Journal of the American Statistical Association, 70,
     120-126.

_S_e_e _A_l_s_o:

     'eigen'

_E_x_a_m_p_l_e_s:

     data(oldcol)
     W.eig <- eigenw(nb2listw(COL.nb, style="W"))
     1/range(W.eig)
     S.eig <- eigenw(nb2listw(COL.nb, style="S"))
     1/range(S.eig)
     B.eig <- eigenw(nb2listw(COL.nb, style="B"))
     1/range(B.eig)

