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How to replace Values after TF-IDF

RucaRuca Member Posts: 13 Contributor II
edited November 2018 in Help
Hi all,

Sorry if this topic was already answered by I was not able to find it.
Here's the situation.
I've perfomed a TF-IDF score to a set of documents and my idea is to get rid of words were their tf-idf score is very low (ex. below 0.001).
How can I "clean" my example set in order to set values that are below 0.001 to 0.
It's not simple to set a word tf-idf score into 0, because a word can have a higher tf-idf in particular document and low values in order documents.
I hope I could made myself clear.
Any help would be very much apreciated.
Thank's a lot

Cheers,

Ruca

Answers

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    MariusHelfMariusHelf RapidMiner Certified Expert, Member Posts: 1,869 Unicorn
    Hi, you can use Generate Attributes to conditionally replace the values of a certain attribute:
    if(myAttribute < 0.001, 0, myAttribute)
    To do this iteratively for all attributes (i.e. words in your case) you can use the aforementioned expression in Generate Attributes together with the Loop Attributes operator.

    Regards,
    Marius
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    RucaRuca Member Posts: 13 Contributor II
    Hi Marius,

    Already implemented your approach. I'm usign the "Loop Attributes" operator, with the "Generate Attributes" in its subprocess.
    It's seems that the loop_attribute generated by the "Loop Attributes" is not recognized inside the "Generate Attributes" operator.
    Shouldn't the loop_attribute be the iterator variable?

    Thank you,

    Ruca
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    RucaRuca Member Posts: 13 Contributor II
    It seems that I'm not able to get it working...
    Do I have to perform a "set macro" somewhere within the process?
    Here's my example.
    Any hint is more than welcome!

    Thanks a lot,

    <?xml version="1.0" encoding="UTF-8" standalone="no"?>
    <process version="5.2.008">
      <context>
        <input/>
        <output/>
        <macros/>
      </context>
      <operator activated="true" class="process" compatibility="5.2.008" expanded="true" name="Process">
        <parameter key="logverbosity" value="all"/>
        <parameter key="logfile" value="H:\SEKS\KnowledgeSources\log.txt"/>
        <parameter key="resultfile" value="H:\SEKS\KnowledgeSources\result.csv"/>
        <parameter key="parallelize_main_process" value="true"/>
        <process expanded="true" height="791" width="815">
          <operator activated="false" class="text:process_document_from_file" compatibility="5.2.004" expanded="true" height="76" name="Process Documents from Files" width="90" x="45" y="30">
            <list key="text_directories">
              <parameter key="Waste Management" value="H:\SEKS\KnowledgeSources\ICONDA\Waste Management\TXT"/>
              <parameter key="Climate Control" value="H:\SEKS\KnowledgeSources\ICONDA\Climate Control\TXT"/>
              <parameter key="Utility &amp; Transportation" value="H:\SEKS\KnowledgeSources\ICONDA\Utility and Transportation\TXT"/>
              <parameter key="Electric Power &amp; Lighting" value="H:\SEKS\KnowledgeSources\ICONDA\Electric Power and Lighting\TXT"/>
              <parameter key="Information &amp; Communication" value="H:\SEKS\KnowledgeSources\ICONDA\Information and Communication\TXT"/>
            </list>
            <parameter key="content_type" value="pdf"/>
            <parameter key="prune_method" value="percentual"/>
            <parameter key="prunde_below_percent" value="2.0"/>
            <parameter key="prune_above_percent" value="100.0"/>
            <parameter key="prune_below_rank" value="0.9"/>
            <parameter key="prune_above_rank" value="0.5"/>
            <parameter key="parallelize_vector_creation" value="true"/>
            <process expanded="true" height="663" width="1094">
              <operator activated="false" class="text:tokenize" compatibility="5.2.004" expanded="true" height="60" name="Tokenize" width="90" x="112" y="75"/>
              <operator activated="false" class="text:transform_cases" compatibility="5.2.004" expanded="true" height="60" name="Transform Cases" width="90" x="112" y="210"/>
              <operator activated="false" class="text:filter_stopwords_english" compatibility="5.2.004" expanded="true" height="60" name="Filter Stopwords (English)" width="90" x="122" y="351"/>
              <operator activated="false" class="text:stem_snowball" compatibility="5.2.004" expanded="true" height="60" name="Stem (Snowball)" width="90" x="112" y="480"/>
              <operator activated="false" class="text:filter_by_length" compatibility="5.2.004" expanded="true" height="60" name="Filter Tokens (by Length)" width="90" x="380" y="480">
                <parameter key="max_chars" value="50"/>
              </operator>
              <operator activated="false" class="text:generate_n_grams_terms" compatibility="5.2.004" expanded="true" height="60" name="Generate n-Grams (Terms)" width="90" x="581" y="345">
                <parameter key="max_length" value="3"/>
              </operator>
              <connect from_port="document" to_op="Tokenize" to_port="document"/>
              <connect from_op="Tokenize" from_port="document" to_op="Transform Cases" to_port="document"/>
              <connect from_op="Transform Cases" from_port="document" to_op="Filter Stopwords (English)" to_port="document"/>
              <connect from_op="Filter Stopwords (English)" from_port="document" to_op="Stem (Snowball)" to_port="document"/>
              <connect from_op="Stem (Snowball)" from_port="document" to_op="Filter Tokens (by Length)" to_port="document"/>
              <connect from_op="Filter Tokens (by Length)" from_port="document" to_op="Generate n-Grams (Terms)" to_port="document"/>
              <connect from_op="Generate n-Grams (Terms)" from_port="document" to_port="document 1"/>
              <portSpacing port="source_document" spacing="0"/>
              <portSpacing port="sink_document 1" spacing="0"/>
              <portSpacing port="sink_document 2" spacing="0"/>
            </process>
          </operator>
          <operator activated="false" class="data_to_similarity" compatibility="5.2.008" expanded="true" height="76" name="Data to Similarity (2)" width="90" x="246" y="435">
            <parameter key="measure_types" value="NumericalMeasures"/>
          </operator>
          <operator activated="false" class="data_to_similarity" compatibility="5.2.008" expanded="true" height="76" name="Data to Similarity" width="90" x="246" y="75">
            <parameter key="measure_types" value="NumericalMeasures"/>
            <parameter key="numerical_measure" value="CosineSimilarity"/>
          </operator>
          <operator activated="false" class="store" compatibility="5.2.008" expanded="true" height="60" name="Store" width="90" x="441" y="59">
            <parameter key="repository_entry" value="ICONDAwl"/>
          </operator>
          <operator activated="false" class="item_distribution_performance" compatibility="5.2.008" expanded="true" height="76" name="Performance (4)" width="90" x="581" y="615"/>
          <operator activated="false" class="cluster_count_performance" compatibility="5.2.008" expanded="true" height="76" name="Performance (3)" width="90" x="581" y="525"/>
          <operator activated="false" class="map_clustering_on_labels" compatibility="5.2.008" expanded="true" height="76" name="Map Clustering on Labels" width="90" x="581" y="705"/>
          <operator activated="false" class="cluster_density_performance" compatibility="5.2.008" expanded="true" height="112" name="Performance" width="90" x="581" y="390"/>
          <operator activated="true" class="retrieve" compatibility="5.2.008" expanded="true" height="60" name="Retrieve" width="90" x="45" y="255">
            <parameter key="repository_entry" value="ICONDA/2nd Iteration/wordlist2"/>
          </operator>
          <operator activated="true" class="loop_attributes" compatibility="5.2.008" expanded="true" height="60" name="Loop Attributes" width="90" x="246" y="255">
            <process expanded="true" height="645" width="1076">
              <operator activated="true" class="generate_attributes" compatibility="5.2.008" expanded="true" height="76" name="Generate Attributes" width="90" x="313" y="30">
                <list key="function_descriptions">
                  <parameter key="loop_attribute" value="if(loop_attribute &lt; 0.001, 0, loop_attribute)"/>
                </list>
              </operator>
              <connect from_port="example set" to_op="Generate Attributes" to_port="example set input"/>
              <connect from_op="Generate Attributes" from_port="example set output" to_port="example set"/>
              <portSpacing port="source_example set" spacing="0"/>
              <portSpacing port="sink_example set" spacing="0"/>
            </process>
          </operator>
          <operator activated="true" class="k_means" compatibility="5.2.008" expanded="true" height="76" name="Clustering" width="90" x="447" y="255">
            <parameter key="k" value="5"/>
            <parameter key="determine_good_start_values" value="true"/>
          </operator>
          <operator activated="true" class="cluster_distance_performance" compatibility="5.2.008" expanded="true" height="94" name="Performance (2)" width="90" x="648" y="255"/>
          <connect from_op="Retrieve" from_port="output" to_op="Loop Attributes" to_port="example set"/>
          <connect from_op="Loop Attributes" from_port="example set" to_op="Clustering" to_port="example set"/>
          <connect from_op="Clustering" from_port="cluster model" to_op="Performance (2)" to_port="cluster model"/>
          <connect from_op="Clustering" from_port="clustered set" to_op="Performance (2)" to_port="example set"/>
          <connect from_op="Performance (2)" from_port="performance" to_port="result 1"/>
          <connect from_op="Performance (2)" from_port="example set" to_port="result 2"/>
          <connect from_op="Performance (2)" from_port="cluster model" to_port="result 3"/>
          <portSpacing port="source_input 1" spacing="0"/>
          <portSpacing port="sink_result 1" spacing="0"/>
          <portSpacing port="sink_result 2" spacing="0"/>
          <portSpacing port="sink_result 3" spacing="0"/>
          <portSpacing port="sink_result 4" spacing="0"/>
        </process>
      </operator>
    </process>
  • Options
    MariusHelfMariusHelf RapidMiner Certified Expert, Member Posts: 1,869 Unicorn
    Hi,

    to access the value of a macro you have to enclose it in curly braces preceded by a percentage sign, like this: %{myMacro}

    Happy Clustering!
    ~Marius
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