bootstrapT            package:maigesPack            R Documentation

_C_a_l_c_u_l_a_t_e _b_o_o_t_s_t_r_a_p _p-_v_a_l_u_e_s _f_o_r _t _s_t_a_t_i_s_t_i_c_s

_D_e_s_c_r_i_p_t_i_o_n:

     This function takes a numerical matrix and column indexes for two
     groups to calculate bootstrapped (by re-sampling) p-values
     comparing the equality of means from the two groups.

_U_s_a_g_e:

     bootstrapT(x, k=20000, obs1, obs2, ...)

_A_r_g_u_m_e_n_t_s:

       x: numerical matrix to be bootstrapped. The t statistics is
          calculated by row using the column indexes given by 'obs1'
          and 'obs2' for the two groups tested.

       k: number of bootstrap re-samplings to be done. Defaults to
          20000.

    obs1: logical or numerical column indexes of the first group.

    obs2: logical or numerical column indexes of the second group.

     ...: additional parameters for 't.test' function from package
          _stats_.

_V_a_l_u_e:

     The result of this function is a numerical matrix with number of
     rows given by the rows of the argument 'x' and 3 columns. The
     first column contain the difference of means between the two
     groups, the second one contain the original t statistic and the
     last one gives the bootstrapped p-values, for all rows of the
     matrix 'x'.

_A_u_t_h_o_r(_s):

     Gustavo H. Esteves <gesteves@vision.ime.usp.br>

_S_e_e _A_l_s_o:

     't.test' from package _stats_.

_E_x_a_m_p_l_e_s:

     z <- matrix(rnorm(100, 0, 1), 4, 25)
     bootstrapT(z, k=100, obs1=1:14, obs2=15:25)

