HairEyeColor            package:datasets            R Documentation

_H_a_i_r _a_n_d _E_y_e _C_o_l_o_r _o_f _S_t_a_t_i_s_t_i_c_s _S_t_u_d_e_n_t_s

_D_e_s_c_r_i_p_t_i_o_n:

     Distribution of hair and eye color and sex in 592 statistics
     students.

_U_s_a_g_e:

     HairEyeColor

_F_o_r_m_a_t:

     A 3-dimensional array resulting from cross-tabulating 592
     observations on 3 variables.  The variables and their levels are
     as follows:

       No  Name  Levels
        1  Hair  Black, Brown, Red, Blond
        2  Eye   Brown, Blue, Hazel, Green
        3  Sex   Male, Female

_D_e_t_a_i_l_s:

     The Hair x Eye table comes rom a survey of students at the
     University of Delaware reported by Snee (1974).  The split by
     'Sex' was added by Friendly (1992a) for didactic purposes.

     This data set is useful for illustrating various techniques for
     the analysis of contingency tables, such as the standard
     chi-squared test or, more generally, log-linear modelling, and
     graphical methods such as mosaic plots, sieve diagrams or
     association plots.

_S_o_u_r_c_e:

     <URL:
     http://euclid.psych.yorku.ca/ftp/sas/vcd/catdata/haireye.sas>

     Snee (1974) gives the two-way table aggregated over 'Sex'.  The
     Sex split of the 'Brown hair, Brown eye' cell was changed in R
     2.6.0 to agree with that used by Friendly (2000).

_R_e_f_e_r_e_n_c_e_s:

     Snee, R. D. (1974) Graphical display of two-way contingency
     tables. _The American Statistician_, *28*, 9-12.

     Friendly, M. (1992a) Graphical methods for categorical data. _SAS
     User Group International Conference Proceedings_, *17*, 190-200.
     <URL: http://www.math.yorku.ca/SCS/sugi/sugi17-paper.html>

     Friendly, M. (1992b) Mosaic displays for loglinear models.
     _Proceedings of the Statistical Graphics Section_, American
     Statistical Association, pp. 61-68. <URL:
     http://www.math.yorku.ca/SCS/Papers/asa92.html>

     Friendly, M. (2000) _Visualizing Categorical Data._ SAS Institute,
     ISBN 1-58025-660-0.

_S_e_e _A_l_s_o:

     'chisq.test', 'loglin', 'mosaicplot'

_E_x_a_m_p_l_e_s:

     require(graphics)
     ## Full mosaic
     mosaicplot(HairEyeColor)
     ## Aggregate over sex (as in Snee's original data)
     x <- apply(HairEyeColor, c(1, 2), sum)
     x
     mosaicplot(x, main = "Relation between hair and eye color")

