Ord                 package:spatstat                 R Documentation

_G_e_n_e_r_i_c _O_r_d _I_n_t_e_r_a_c_t_i_o_n _m_o_d_e_l

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

     Creates an instance of an Ord-type interaction point process model
     which can then be fitted to point pattern data.

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

       Ord(pot, name)

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

     pot: An S language function giving the user-supplied interaction
          potential.

    name: Character string.

_D_e_t_a_i_l_s:

     Ord's point process model (Ord, 1977) is a Gibbs point process of
     infinite order. Each point x[i] in the point pattern x contributes
     a factor g(a[i]) where a[i] = a(x[i], x) is the area of the tile
     associated with x[i] in the Dirichlet tessellation of x.

     Ord (1977) proposed fitting this model to forestry data when g(a)
     has a simple ``threshold'' form. That model is implemented in our
     function `OrdThresh'. The present function `Ord' implements the
     case of a completely general Ord potential g(a) specified as an S
     language function `pot'.

     This is experimental.

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

     An object of class `"interact"' describing the interpoint
     interaction structure of a point process.

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

     Adrian Baddeley adrian@maths.uwa.edu.au <URL:
     http://www.maths.uwa.edu.au/~adrian/> and Rolf Turner
     rolf@math.unb.ca <URL: http://www.math.unb.ca/~rolf>

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

     Baddeley, A. and Turner, R. (2000) Practical maximum
     pseudolikelihood for spatial point patterns. Australian and New
     Zealand Journal of Statistics 42, 283-322.

     Ord, J.K. (1977)  Contribution to the discussion of Ripley (1977).

     Ord, J.K. (1978)  How many trees in a forest? Mathematical
     Scientist 3, 23-33.

     Ripley, B.D. (1977) Modelling spatial patterns (with discussion).
     Journal of the Royal Statistical Society, Series B, 39, 172 - 212.

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

     `mpl', `ppm.object', `OrdThresh'

