QQplot                package:UsingR                R Documentation

_C_r_e_a_t_e_s _a _q_q_p_l_o_t _w_i_t_h _s_h_a_d_e_d _d_e_n_s_i_t_y _e_s_t_i_m_a_t_e

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

     Creates a qqplot of two variables along with graphs of their
     densities, shaded so that the corresponding percentiles are
     clearly matched up.

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

     QQplot(x, y, n = 20, xsf = 4, ysf = 4, main = "qqplot", xlab = deparse(substitute(x)), ylab = deparse(substitute(y)), pch = 16, pcol = "black", shade = "gray", ...)

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

       x: The x variable

       y: The y variable 

       n: number of points to plot in qqplot. 

     xsf: scale factor to adjust size of x density graph 

     ysf: scale factor to adjust size of y density graph 

    main: title 

    xlab: label for x axis 

    ylab: label for y axis 

     pch: plot character for points in qqplot 

    pcol: color of plot character 

   shade: shading color 

     ...: extra arguments passed to 'plot.window' 

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

     Shows density estimates for the two samples in a qqplot. Meant to
     make this useful plot more transparent to first-time users of
     quantile-quantile plots.

     This function has some limitations: the scale factor may need to
     be adjusted; the code to shade only shaded trapezoids, and does
     not completely follow the density.

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

     Produces a graphic

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

     John Verzani

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

     'qqplot', 'qqnorm'

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

     x = rnorm(100)
     y = rt(100, df=3)
     QQplot(x,y)

