pathCEF              package:adaptTest              R Documentation

_F_u_n_c_t_i_o_n _t_o _p_l_o_t _s_e_v_e_r_a_l _c_o_n_d_i_t_i_o_n_a_l _e_r_r_o_r _f_u_n_c_t_i_o_n_s _r_u_n_n_i_n_g _t_h_r_o_u_g_h _a "_p_a_t_h" _o_f _g_i_v_e_n _p_o_i_n_t_s

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

     This function plots several conditional error functions of the
     same family such that each one runs through one of several given
     points.

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

     pathCEF(typ = NA, fun = NA, dis = NA, p1 = 1:49/50, p2 = p1,
             x = 0:200/200, plt.pt = FALSE, plt.ptann = FALSE, xlab = NA, ylab = NA, ...)

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

     typ: type of test: '"b"' for Bauer and Koehne (1994), '"l"' for
          Lehmacher and Wassmer (1999), '"v"' for Vandemeulebroecke
          (2006) and '"h"' for the horizontal conditional error
          function

     fun: a conditional error function

     dis: a distortion method for a supplied conditional error function
          (see details): '"pl"' for power lines, '"vt"' for vertical
          translation

      p1: a vector (at least of length 2) of p-values p1 of the test
          after the first stage

      p2: a vector (at least of length 2) of p-values p2 of the test
          after the second stage, defaults to 'p1'; must be of same
          length as 'p1'

       x: vector on which the conditional error functions are plotted
          (should be relatively dense in [0,1])

  plt.pt: logical determining whether the points that the conditional
          error functions are made to run through should be plotted or
          not (default: not)

plt.ptann: logical determining whether the points that the conditional
          error functions are made to run through should be annotated
          or not (default: not)

    xlab: a label for the x axis (default: no label)

    ylab: a label for the y axis (default: no label)

     ...: arguments to be passed on to the underlying 'plot' and
          'points' functions (e.g., graphical parameters)

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

     It can be instructive to plot not only one conditional error
     function, but to visualize a whole family. This can easily be done
     with 'pathCEF'. The function is used in a similar way as
     'plotCEF', but 'p1' and 'p2' are now vectors (of the same length,
     at least of length 2). Conditional error functions are plotted
     that run through the specified elementwise points '(p1,p2)' (which
     by default lie on the main diagonal).

     Internally, 'pathCEF' uses 'plotCEF' to plot the individual
     conditional error functions; see this latter function for further
     details.

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

     The function 'pathCEF' is invoked for its plotting effect; it
     returns no meaningful value.

_N_o_t_e:

     Provide either 'typ' or 'fun', not both! If 'fun' is provided,
     then also specify 'dis'. 

     Unlike 'plotCEF', it is not possible with 'pathCEF' to specify the
     conditional error functions by the parameter alpha2 or the
     parameter c. 

     'plt.ptann' is not considered if 'plt.pt = FALSE'.

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

     Marc Vandemeulebroecke

_R_e_f_e_r_e_n_c_e_s:

     Bauer, P., Koehne, K. (1994). Evaluation of experiments with
     adaptive interim analyses. _Biometrics_ 50, 1029-1041.

     Lehmacher, W., Wassmer, G. (1999). Adaptive sample size
     calculations in group sequential trials. _Biometrics_ 55,
     1286-1290.

     Vandemeulebroecke, M. (2006). An investigation of two-stage tests.
     _Statistica Sinica_ 16, 933-951.

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

     'adaptTest' package description, 'CEF', 'plotCEF', 'tsT'

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

     ## Compare the tests by Bauer and Koehne (1994), Lehmacher and Wassmer (1999) and Vandemeulebroecke (2006)
     oldmfcol <- par(mfcol=c(1,3))
     pathCEF(typ="b", main="BK 94")
     pathCEF(typ="l", main="LW 99")
     pathCEF(typ="v", main="V 06")
     par(oldmfcol)

