MultiStraussHard          package:spatstat          R Documentation

_T_h_e _M_u_l_t_i_t_y_p_e/_H_a_r_d _C_o_r_e _S_t_r_a_u_s_s _P_o_i_n_t _P_r_o_c_e_s_s _M_o_d_e_l

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

     Creates an instance of the multitype/hard core Strauss point
     process model which can then be fitted to point pattern data.

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

       MultiStraussHard(types, iradii, hradii)

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

   types: Vector of all possible types (i.e. the possible levels of the
          `marks' variable in the data)

  iradii: Matrix of interaction radii

  hradii: Matrix of hard core radii

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

     This is a hybrid of the multitype Strauss process (see
     `MultiStrauss') and the hard core process (case gamma = 0 of the
     Strauss process). A pair of points of types i and j must not lie
     closer than h[i,j] units apart; if the pair lies more than h[i,j]
     and less than  r[i,j] units apart, it contributes a factor
     gamma[i,j] to the probability density.

     The matrices `iradii' and `hradii' must be symmetric, with entries
     which are either positive numbers or `NA'.  A value of `NA'
     indicates that no interaction term should be included for this
     combination of types.

     Note that only the interaction radii and hardcore radii are
     specified in `MultiStraussHard'. The canonical parameters
     log(beta[j]) and log(gamma[i,j]) are estimated by `mpl()', not
     fixed in `MultiStraussHard()'.

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

     An object of class `"interact"' describing the interpoint
     interaction structure of the multitype/hard core Strauss process
     with interaction radii iradii[i,j] and hard core radii
     hradii[i,j].

_W_a_r_n_i_n_g_s:

     The argument `types' is interpreted as a set of factor levels.
     That is, in order that `mpl' can fit the multitype Strauss model
     correctly to a point pattern `X', this must be a marked point
     pattern; the mark vector `X$marks' must be a factor; and  the
     argument `types' must equal `levels(X$marks)'.

_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>

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

     `mpl', `pairwise.family', `ppm.object', `MultiStrauss', `Strauss'

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

        library(spatstat)
        r <- matrix(3, nrow=2,ncol=2)
        h <- matrix(c(1,2,2,1), nrow=2,ncol=2)
        MultiStraussHard(1:2, r, h)
        # prints a sensible description of itself
        data(catWaessle)
        r <- 0.03 * matrix(c(1,2,2,1), nrow=2,ncol=2)
        h <- 0.03 * matrix(c(NA,1,1,NA), nrow=2,ncol=2)
        mpl(catWaessle, ~1, MultiStraussHard(c("0","1"), r, h), rbord=0.06)
        # fit the stationary multitype hardcore Strauss process to `catWaessle'

