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            <h2><font color="#ffffff">Search Algorithms: iMAGES</font></h2>
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<p>iMAGES (Model Averaging GES) is the GES algorithm, using a model
    averaging BIC score that lets the algorithm search over multiple data
    sets simultaneously. For a description of the GES algoritihm, see <a
            href="ges.html">GES</a>.</p>

<p>iMAGES takes as input a list of continuous data sets D1 through Dn,
    all of which contain the same varibles, in the same order, and all of
    which contain the same number of cases. (The discrete case has not
    been tested.</p>

<p>The BIC score of iMAGES, for a given structural hypothesis in the
    form of a DAG G, is the average of the BIC scores for G with respect
    to each data sets Di, i = 1,...,10. The search proceeds in the order
    of GES--that is, calculating the score of the empty graph, then
    finding the edge that most increases the average BIC score and adding
    that, and so on.</p>

<p>A "discount penalty" may be applied, which multiplies the penalty
    part of the BIC score by the given number (or, equivalently, divides
    the likelihood part by the given number--a simpler interpretation when
    nonlinear functions are involved in generating the data).</p>

<p>Figure 1 shows the current dialog for this search, which includes
    an untested discrete sections.</p>

<div align="center"><img src="../../images/images.png" alt="iMAGES
dialog"></div>
<div align="center">Figure 1</div>

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