getVariance            package:beadarray            R Documentation

_G_e_t_s _t_h_e _b_e_a_d-_t_y_p_e _v_a_r_i_a_n_c_e_s _f_r_o_m _a_n _E_x_p_r_e_s_s_i_o_n_S_e_t_I_l_l_u_m_i_n_a _O_b_j_e_c_t

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

     Calculates the variance for each bead-type on each array from an
     'ExpressionSetIllumina' object.

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

     getVariance(object, offset=0)

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

  object: 'ExpressionSetIllumina' object

  offset: numeric value to add to the variances to avoid very small
          values

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

     'getVariance' uses the 'se.exprs' and 'NoBeads' slots in
     'assayData' to calculate the variances for each bead-type on each
     array.

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

     A matrix containing the variances.

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

     Matt Ritchie

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

     data(BSData)
     v = getVariance(BSData)
     boxplot(as.data.frame(log2(v)), ylab="log2var", xlab=colnames(BSData), las=2)

