ONEWAY(1)                          |STAT                  December 24, 1986

NAME
     oneway - one way analysis of variance / t-test

SYNOPSIS
     oneway [-ptu] [-w plotwidth] [-s splitter] [names]

DESCRIPTION
     _o_n_e_w_a_y does a one-way analysis of variance on data from different
     groups.  These groups can have different cell sizes.  When cell sizes
     are equal across groups, the unweighted means analysis and the
     weighted means solutions produce identical results.  When cell sizes
     are unequal, the preferred analysis depends on the reasons for unequal
     cell sizes.  A text should be consulted to decide which test is most
     appropriate.

     The input format is simple: each group's data is separated from other
     groups' by including a special value, called the splitter.

OPTIONS
     Group names can be supplied on the command line.  Otherwise, names
     like ``Group-1'' are used.

     -p   Print error bar plots of each group.  The wide line of dashes is
          two standard deviations on each side of the mean of each group.
          The narrower double line is one standard deviation on each side.
          Single standard errors are marked with parentheses.  The mean of
          each group is marked with a pound sign.  The minimum and maximum
          values are delimited by angle brackets.

     -s splitter
          This value is used to tell when one group's data ends and
          another's begins.

     -t   Request a between group's t-test format for the significance
          test.  This option is ignored if there are not two groups.

     -u   Request unweighted means solution rather than the default
          unweighted.

     -w plotwidth
          Set the width of the error bar plot to a value other than the
          default 60.

EXAMPLE
     Suppose you had two groups of data in two files, called ``long'' and
     ``short.'' To compare these, you would do something like:
             echo 999 | cat long - short | oneway -s 999 long short

ALGORITHMS
     The weighted means analysis algorithm follows Guilford & Fruchter's
     _F_u_n_d_a_m_e_n_t_a_l _S_t_a_t_i_s_t_i_c_s _f_o_r _P_s_y_c_h_o_l_o_g_y _a_n_d _E_d_u_c_a_t_i_o_n (_5_t_h _E_d_i_t_i_o_n). The
     unweighted means solution follows Keppel's _D_e_s_i_g_n _a_n_d _A_n_a_l_y_s_i_s: _A
     _R_e_s_e_a_r_c_h_e_r'_s _H_a_n_d_b_o_o_k.

LIMITS
     Use the -L option to determine the program limits.

MISSING VALUES
     Missing data values (NA) are counted but not included in the analysis.

SEE ALSO
     rankind(1) for a non-parametric rank order version of the analysis.
