pairwise.t.test            package:stats            R Documentation

_P_a_i_r_w_i_s_e _t _t_e_s_t_s

_D_e_s_c_r_i_p_t_i_o_n:

     Calculate pairwise comparisons between group levels with
     corrections for multiple testing

_U_s_a_g_e:

     pairwise.t.test(x, g, p.adjust.method=p.adjust.methods, pool.sd=TRUE, ...)

_A_r_g_u_m_e_n_t_s:

       x: Response vector 

       g: Grouping vector or factor 

p.adjust.method: Method for adjusting p values (see 'p.adjust') 

 pool.sd: Switch to allow/disallow the use of a pooled SD 

     ...: Additional arguments to pass to 't.test' 

_V_a_l_u_e:

     Object of class '"pairwise.htest"'

_S_e_e _A_l_s_o:

     't.test', 'p.adjust'

_E_x_a_m_p_l_e_s:

     data(airquality)
     attach(airquality)
     Month <- factor(Month, labels = month.abb[5:9])
     pairwise.t.test(Ozone, Month)
     pairwise.t.test(Ozone, Month, p.adj = "bonf")
     pairwise.t.test(Ozone, Month, pool.sd = FALSE)
     detach()

