ratioLoadings          package:compositions          R Documentation

_L_o_a_d_i_n_g_s _o_f _r_e_l_a_t_i_o_n_s _o_f _t_w_o _a_m_o_u_n_t_s

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

     In a compositional dataset the relation of two objects can be
     interpreted better than a single amount. These functions compute,
     display and plot the corresponding pair-information for the
     various principal component analysis results.

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

     relativeLoadings(x,...)
     ## S3 method for class 'princomp.acomp':
     relativeLoadings(x,...,log=FALSE,scale.sdev=NA,cutoff=0.1)
     ## S3 method for class 'princomp.aplus':
     relativeLoadings(x,...,log=FALSE,scale.sdev=NA,cutoff=0.1)
     ## S3 method for class 'princomp.rcomp':
     relativeLoadings(x,...,scale.sdev=NA,cutoff=0.1)
     ## S3 method for class 'princomp.rplus':
     relativeLoadings(x,...,scale.sdev=NA,cutoff=0.1)
     ## S3 method for class 'relativeLoadings.princomp.acomp':
     print(x,...,cutoff=attr(x,"cutoff"),
                                                      digits=2
                                                      )
     ## S3 method for class 'relativeLoadings.princomp.aplus':
     print(x,...,cutoff=attr(x,"cutoff"),
                                                      digits=2
                                                      )
     ## S3 method for class 'relativeLoadings.princomp.rcomp':
     print(x,...,cutoff=attr(x,"cutoff"),
                                                      digits=2
                                                      )
     ## S3 method for class 'relativeLoadings.princomp.rplus':
     print(x,...,cutoff=attr(x,"cutoff"),
                                                      digits=2
                                                      )
     ## S3 method for class 'relativeLoadings.princomp.acomp':
     plot(x,...)
     ## S3 method for class 'relativeLoadings.princomp.aplus':
     plot(x,...)
     ## S3 method for class 'relativeLoadings.princomp.rcomp':
     plot(x,...)
     ## S3 method for class 'relativeLoadings.princomp.rplus':
     plot(x,...)

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

       x: a result from an amount PCA
          'princomp.acomp'/'princomp.aplus'/'princomp.rcomp'/'princomp.
          rplus'

     log: a logical indicating to use log-ratios instead of ratios

scale.sdev: If not 'NA', a number specifying the multiple of a standard
          deviation the component is to be multiplied with.

  cutoff: A single number. Changes under that (log)-cutoff are not
          displayed.

  digits: The number of digits to be displayed

     ...: further parameters to internally-called functions

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

     The relative loadings of components allow a direct interpretation
     of the effects of principal components. For acomp/aplus classes
     the relation is induced by a ratio, which can optionally be
     log-transformed. For the rcomp/rplus-classes the relation is
     induced by a difference, which is quite meaningless when the units
     are different.

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

     The value is a matrix of type '"relativeLoadings.princomp.*"',
     containing the ratios in the compositions represented by the
     loadings (optionally scaled by the standard deviation of the
     components and 'scale.sdev').

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

     'princomp.acomp',   'princomp.aplus', 'barplot'

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

     data(SimulatedAmounts)
     pc <- princomp(acomp(sa.lognormals5))
     pc
     summary(pc)
     relativeLoadings(pc,log=TRUE)
     relativeLoadings(pc)
     relativeLoadings(pc,scale.sdev=1)
     relativeLoadings(pc,scale.sdev=2)

     plot(relativeLoadings(pc,log=TRUE))
     plot(relativeLoadings(pc))
     plot(relativeLoadings(pc,scale.sdev=1))
     plot(relativeLoadings(pc,scale.sdev=2))

