subclassify             package:MatchIt             R Documentation

_S_u_b_c_l_a_s_s_i_f_y _u_n_i_t_s

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

     This is a sub-function of 'matchit' which generates subclasses of
     units given a propensity score.

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

     subclassify <- subclassify(formula, data, in.sample, pscore, nearest=TRUE, match.matrix, 
                     subclass=0, sub.by="treat", counter=TRUE, full=FALSE, full.options=list())

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

 formula: (required).  Takes the form of 'T ~ X1 + X2', where 'T' is a
          binary treatment indicator and 'X1' and 'X2' are the
          pre-treatment covariates, and 'T', 'X1', and 'X2' are
          contained in the same data frame.  The '+' symbol means
          "inclusion" not "addition." You may also include interaction
          terms in the form if 'I(X1*X2)' or squared terms in the form
          of 'I(X1^2)'.

    data: (required).  Data frame containing the variables called in
          the 'formula'.   The dataframe should not include variables
          with the names 'psclass', 'psweights', or 'pscore', as these
          are expressly reserved in the output dataframe for MatchIt.

in.sample: (required).  Vector of length n showing whether each unit
          was eligible for matching due to common support restrictions
          with 'discard'.  Generally created by 'distance'.

  pscore: (required).  Vector of estimated propensity scores. 
          Generally created by 'distance'.

 nearest: Whether to perform nearest-neighbor matching (default=TRUE).  

match.matrix: (required) n1 by ratio data frame where the rows
          correspond to treated units and the columns store the names
          of the control units matched to each treated unit.  NA
          indicates that treated unit was not matched.  Generally
          created by 'matchdef'.

subclass: Either a scaler specifying the number of subclasses
          (default=0) or a vector of probabilities to create quantiles
          based on 'sub.by'.

  sub.by: If 'subclass!=0', by what criteria to subclassify.  "treat"
          (default) =by the number of treated units, "control"=by the
          number of control units, "all"=by the total number of units.

 counter: Whether to display counter indicating the progress of the
          matching (default=TRUE).

    full: Whether to do full matching (default=FALSE).  Requires
          ``optmatch" package.

full.options: Additional options for full matching.

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

     This function creates subclasses of units based on their covariate
     values, usually defined by the propensity score.  This function is
     called directly by 'matchit' and does not generally need to be
     called directly by users; these details are included for advanced
     users.

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

 psclass: Subclass index in an ordinal scale from 1 to the number of
          subclasses.   Unmatched units have subclass=0.

   q.cut: Subclass cut points.

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

     Daniel Ho <deho@fas.harvard.edu>;  Kosuke Imai
     <kimai@princeton.edu>; Gary King <king@harvard.edu>; Elizabeth
     Stuart<stuart@stat.harvard.edu>

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

     Please use 'help.matchit' to access the matchit reference manual. 
     The complete document is available online at <URL:
     http://gking.harvard.edu/matchit>.

