scaler                package:mvpart                R Documentation

_R_o_w _a_n_d _C_o_l_u_m_n _S_c_a_l_i_n_g _o_f _a _D_a_t_a _M_a_t_r_i_x

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

     The function provides some popular (and effective) standardization
     methods for community ecologists.

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

     scaler(x, col = NULL, row=NULL)

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

       x: Data matrix.

     col: Character vector of column standardizations.

     row: Character vector of row standardizations.

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

     The function offers following data matrix standardizations:

        *  'mean1 ': scale to mean of 1.

        *  'max1 ': scale to maximum of 1.

        *  'ssq1 ': scale to sums of sqaures equal 1.

        *  'range01 ': scale range to 0-1.

        *  'zsc ': standardize to z-scores (mean=0, sd=1).

        *  'pa ': scale to presence/absence scale (0/1).

        *  'rank ': scale to rank order (1=lowest).

     Standardizations are performed first on columns then on rows. "pa"
     applies to the whole matrix and can be specied using row or col.

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

     Returns the standardized matrix.

_N_o_t_e:

     Common transformations can be made with standard R functions.

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

     Jari Oksanen - modified Glenn De'ath (Dec 03)

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

     data(spider)
     spid.data <- scaler(spider, col = "max", row="mean1")

