KNN Classification

Shubha

Hi,

I run the below code given in the sample XML files (04_NearestNeighbours.XML) for the KNN Classification.

<operator name="Root" class="Process" expanded="yes">
    <description text="This learner uses a simple nearest neighbors classifier. This instance based classifiers just uses the other instances closest to the instance at hand in order to determine a prediction."/>
    <operator name="ArffExampleSource" class="ArffExampleSource">
        <parameter key="data_file"	value="../data/iris.arff"/>
        <parameter key="label_attribute"	value="class"/>
    </operator>
    <operator name="NearestNeighbors" class="NearestNeighbors">
        <parameter key="keep_example_set"	value="true"/>
        <parameter key="k"	value="3"/>
    </operator>
</operator>

But the result I get is a blank KNNClassification model with the contents,

KNNClassification KNNClassification (prediction model for label class)

and an id attribute added into the Exampleset.

Why are the results not displayed?

Thanks,
Shubha

keith

You created a model, but did not apply it to the dataset.  Applying the model is what generates predictions.  You need to add a ModelApplier node after creating the model.  ry this instead:

<operator name="Root" class="Process" expanded="yes">
    <description text="This learner uses a simple nearest neighbors classifier. This instance based classifiers just uses the other instances closest to the instance at hand in order to determine a prediction."/>
    <operator name="ArffExampleSource" class="ArffExampleSource">
        <parameter key="data_file"	value="../data/iris.arff"/>
        <parameter key="label_attribute"	value="class"/>
    </operator>
    <operator name="NearestNeighbors" class="NearestNeighbors">
        <parameter key="keep_example_set"	value="true"/>
        <parameter key="k"	value="3"/>
    </operator>
    <operator name="ModelApplier" class="ModelApplier">
        <list key="application_parameters">
        </list>
    </operator>
</operator>