tmixture                package:limma                R Documentation

_E_s_t_i_m_a_t_e _S_c_a_l_e _F_a_c_t_o_r _i_n _M_i_x_t_u_r_e _o_f _t-_D_i_s_t_r_i_b_u_t_i_o_n_s

_D_e_s_c_r_i_p_t_i_o_n:

     This function estimates the unscaled standard deviation of the log
     fold change for differentially expressed genes. It is called by
     the function 'ebayes' and is not intended to be called by users.

_U_s_a_g_e:

     tmixture.vector(tstat,stdev.unscaled,df,proportion,v0.lim=NULL)
     tmixture.matrix(tstat,stdev.unscaled,df,proportion,v0.lim=NULL)

_A_r_g_u_m_e_n_t_s:

   tstat: numeric vector or matrix of t-statistics

stdev.unscaled: numeric matrix conformal with 'tstatf' containing the
          unscaled standard deviations for the coefficient estimators

      df: numeric vector giving the degrees of freedom associated with
          'tstat'

proportion: assumed proportion of genes which are differentially
          expressed

  v0.lim: numeric vector of length 2, assumed lower and upper limits
          for the estimated unscaled standard deviation

_D_e_t_a_i_l_s:

     The values in each column of 'tstat' are assumed to follow a
     mixture of an ordinary t-distribution, with mixing proportion
     '1-proportion', and '(v0+v1)/v1' times a t-distribution, with
     mixing proportion 'proportion'. Here 'v1=stdev.unscaled^2' and
     'v0' is the value to be estimated.

_V_a_l_u_e:

     Numeric vector of length equal to the number of columns of 'tstat'
     and 'stdev.unscaled'.

_A_u_t_h_o_r(_s):

     Gordon Smyth

_S_e_e _A_l_s_o:

     'ebayes'

