signorm                package:dprep                R Documentation

_S_i_g_m_o_i_d_a_l _N_o_r_m_a_l_i_z_a_t_i_o_n

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

     Function that performs sigmoidal normalization.

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

     signorm(data)

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

    data: the dataset to be normalized, including classes

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

     This method transforms the input data nonlinearly into [-1,1]
     using a sigmoid function. The original data is first centered
     about the  mean, and then mapped to the almost linear region of
     the sigmoid. Is especially appropriate when outlying values are
     present.

     Removes classes before normalization, and returns normalized data
     set complete with classes rejoined.

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

 sigdata: original dataset normalized

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

     Caroline Rodriguez and Edgar Acuna

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

     Hann, J., Kamber, M. (2000). Data Mining: Concepts and Techniques.
      Morgan Kaufman Publishers.

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

     #---- Sigmoidal Normalization ---
     data(vehicle)
     vehicle.signorm=signorm(vehicle)
     op=par(mfrow=c(2,1))
     plot(vehicle[,1])
     plot(vehicle.signorm[,1])
     par(op)

