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help for scm
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Social Cognitive Mapping

        scm infilename , [ options ]

Description

    scm processes group nomination data described by infilename for the
    detection of interaction, conomination, and similarity groups using
    Cairns' "Social Cognitive Mapping" procedure.  This command does not
    affect the data in memory.


Options
    reporters(int) reports interaction groups and their corresponding levels
        of consensus; int specifies the number of respondents providing
        reports of group membership.
    conom(diagonal | normalize) specifies special treatment of the
        co-nomination matrix (see notes below).
    minsim(real) dichotomizes the similarity matrix such that Aij = 1 if the
        Pearson correlation coefficient of i's and j's conomination profiles
        is at least real, and otherwise is 0.
    savelog(outfilename) saves the displayed output as a text file named
        outfilename.txt.
    savematrix(outfilename) saves the co-nomination matrix as a
        comma-delimited file named outfilename_conom.csv, and the similarity
        matrix as a comma-delimited file named outfilename_sim.csv.
    noisolates excludes from analysis all individuals who were not nominated
        as a member of any group.


Treatment of the co-nomination matrix
    By default, the co-nomination matrix includes only off-diagonal cells, in
    which Aij = the number of times individual i and j were named as members
    of the same group.  The conom option can be used to modify this:
      conom(diagonal) specifies that the diagonal cells be included in the
      co-nomination matrix, where Aii = the total number of times that
      individual i was named as a member of any group.  This option yields
      results that mirror those produced by the SCM 4.0 software, but is
      not recommended because the resulting "similarity" matrix cannot be
      interpreted as displaying similarities in individuals' co-nomination
      profiles.

      conom(normalize) specifies that the off-diagonal cell values, Aij, be
      normalized to control for the total number of times that individuals
      i and j were each nominated as group members.


Input
    infilename must be a comma-delimited file in which rows represent
    individuals, and columns represent reported group memberships, such that
    cell Aij = 1 if person i is reported to be a member of group j, and
    otherwise is 0.  The first column must contain IDs, which may include any
    combination of numbers and letters.


References
Neal, J. W., Neal, Z. P.  (In press).  The multiple meanings of peer groups in
     social cognitive mapping, Social Development doi:
     10.1111/j.1467-9507.2012.00656.x.

Cairns, R. B., Perrin, J. E., & Cairns, B. D.  (1985).  Social structure and
     social cognition in early adolescence: Affiliative patterns, The Journal
     of Early Adolescence, 5, 339-355.


Author
Zachary Neal
Department of Sociology
Michigan Sate University
zpneal@msu.edu