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'

