regTermTest              package:survey              R Documentation

_W_a_l_d _t_e_s_t _f_o_r _a _t_e_r_m _i_n _a _r_e_g_r_e_s_s_i_o_n _m_o_d_e_l

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

     Provides a Wald test of the hypothesis that all coefficients
     associated with a particular regression term are zero (or have
     some other specified values). Particularly useful as a substitute
     for 'anova' when not fitting by maximum likelihood.

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

     regTermTest(model, test.terms, null=NULL)

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

   model: A model object with 'coef' and 'vcov' methods

test.terms: Character string or one-sided formula giving name of term
          or terms to test

    null: Null hypothesis values for parameters. Default is zeros

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

     An object of class 'regTermTest'.

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

     'anova', 'vcov', 'contrasts'

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

      data(esoph)
      model1 <- glm(cbind(ncases, ncontrols) ~ agegp + tobgp * 
          alcgp, data = esoph, family = binomial())
      anova(model1)

      regTermTest(model1,"tobgp")
      regTermTest(model1,"tobgp:alcgp")
      regTermTest(model1, ~alcgp+tobgp:alcgp)

