Best Practices: Finding and classifying similar documents

This topic describes how to use the Shinydocs Cognitive Suite and Discovery Search to classify documents based on their “similarity” to other, already classified documents, in the Analytics Engine.

For example, you can choose 5–20 documents of a similar kind and classify them by their document type, such as offer letters or purchase orders. The Shinydocs Cognitive Suite will “learn” from those examples and will be able to find other similar documents for classification.

Throughout this topic, we will use financial planning concepts as examples in many cases (including in .bat and .json files). Please replace these examples with your own terms where appropriate.

Getting started  

Before you begin, the dataset must have been:

1. Crawled for metadata

2. Full text extracted

Applying ROT rules (and cleaning up that ROT) is strongly recommended. 

Classify by Find Similar

Classify by Find Similar is a process that uses a small set of example documents that are about a particular topic (or classification). Once example documents are identified, their structure will be used to find other similar documents and automatically classify them.

This topic is demonstrated using OpenText™ Content Server but can be applied to other sources for your dataset with some adjustments.

Step 1 – Create an enrichment tag in Discovery Search

Before discovering and tagging example documents in Discovery Search, you need to set up an enrichment tag for this.

Create an enrichment tag

1. Open Discovery Search as an Admin

2. Click Enrichment tags on the left navigation panel

3. Specify a name for your enrichment tag (for example, TAG-find-similar)

4. Click Save changes

Optional (but recommended) – Create a result tag

1. Click Result tags on the left navigation panel

2. Select enrichmentTags in the Index field name field

3. Specify the name of your enrichment tag in the Value field

4. Select a color in the Style field

5. Specify a name for your result tag (for example, Find Similar Tag) in the Text field

6. Click Save Changes

Now, any search results in Discovery Search that include your enrichment tag are highlighted with the result tag.

Step 2 – Tag example documents in Discovery Search

In Discovery Search, apply your enrichment tag to approximately 5–20 of the “best” example documents, so they can be used to find other similar documents. 

1. Open Discovery Search

2. Log on to OpenText™ Content Server

3. Search for relevant terms to find your example documents
   For example, if you want to classify documents related to financial planning, you could use search queries like corporate financial planning, finances, and budget.

4. Review the search results for relevant documents. For each relevant document (at least 5):

   1. Toggle on Enrichment view

   2. Check the box for your enrichment tag

   3. Click Save changes

5. Toggle off Enrichment view
   Documents with your enrichment tag are now highlighted with the result tag.

6. 

   Validate your set of example documents in Discovery Search using enrichment tags: [your enrichment tag] as your search term
   We recommend opening each example document again in their native application for final validation.

Step 3 – Determine parameters for the .bat and .json files in the Visualizer

After tagging example documents with your enrichment tag, you can use the Visualizer to determine how to modify the .bat and .json files to support your use case.

1. Make sure your Open Clustering visualization is pointing to the correct Index (shiny-cs in this example)

2. Assuming this has already been set up by your Administrator, open the Open Clustering Dashboard and add a filter for enrichmentTags.keyword is [your enrichment tag]

3. Click Save

4. Scroll down to view the Open Clustering visualization. Using this visualization, you should be able to determine values for the following parameters:

   1. Tokens: --tokens

   2. Minimum documents: --min-docs

   3. Minimum terms: --min-terms

   4. Minimum word length: --min-word-length

   5. Threshold: --threshold

   6. Match: --match

Example: Determining parameters for the .bat and .json files using Open Clustering visualization

In this graph, we are reviewing an Open Clustering visualization of a set of example documents tagged with an enrichment tag. What this graph shows are the words or terms that are used a lot in those selected documents, that are likewise NOT used very much in the rest of the index (these are words likely to be associated with financial planning). These words provide insight into how we can configure the following parameters for the Find Similar Classification process:

• Tokens: For the 100 top words (or tokens) listed, note the drop-off after the word “blue”. The words listed above this are used a lot in all of these documents, but those below not so much. So, we should consider that and the 42 words above it. --tokens 42

• Minimum Documents: With our example document set (33,000 documents), the minimum number of emails in which the word must occur for it to be considered should be about 20. This would most likely be either higher for a larger dataset, or lower for a smaller one. --min-docs: 20

• Minimum Terms: Since many of these documents (emails in this example) include attached spreadsheets, the minimum number of times that the word must occur in order for it to be considered can be fairly high. --min-terms: 20

• Minimum Word Length: In looking at the above graph, there are a few words we want to consider that are only 3 letters in length, so we should likely include those. Generally we want to make this number a little higher in most cases (4 or 5) if we can, however your Open Clustering visualization should guide you. --min-word-length: 3

• Threshold: This is a measure for the words that will occur in different documents, for the words we are considering, how many of these (by percentage) need to be the same for them to be considered similar. A good starting point is 90%. --threshold: 90

• Match: For a given document to be considered “similar” to the original set of example documents, this is the number of documents it needs to match. Since our document set is only 6, this is set to a low value. If our example document set was larger (say 20, 30, or 40), we might want to consider setting this to 2, 3, or 4. --match: 1

Step 4 – Modify .bat and .json files

With the above parameters determined, it is time to modify the supplied .bat and .json files for your use case.

We recommend using a code editor, such as NotePad++, to edit these files.

1. Download the CS - find similar classification.zip provided in the Resources for this topic

2. Create a folder named COG Batch Files in the same folder your CognitiveToolkit.exe is located

3. Unzip the contents of the zip file into the COG Batch Files folder

4. If applicable, edit the file contents and file names to reflect your use case by replacing financial-planning with something more specific to your use case
   * Note: These files can be copied/duplicated for each of the classifications that you wish to use.

5. These .bat files are configured to run on a system in which the IndexName is shiny-cs and the IndexURL is http://localhost:9200. Change these values so that they point to your specific environment URL and index name

6. The .bat files are configured to use the TAG-find-similar enrichment tag. Change these values so that they use the enrichment tag name you created in Step 1 – Create an enrichment tag in Discovery Search.

7. Run the .bat files in the following sequence:

   1. COG-RunScript-Tag-CS-classification-example-financial-planning.bat – In the Index, each enrichmentTags field with your enrichment tag creates a new classification-example field with the value financial planning

   2. COG-Query-FindSimilarClassification-financial-planning.bat – In the Index, based on the classification-example field, for the specified parameters (--tokens, --min-docs, etc.), run the Shinydocs FindSimilarClassification field. This .bat file is where you should apply your edits to the options as determined in Step 3 - Determine parameters for the .bat and .json files in the Visualizer. The result of running this process is that matching Index records are tagged with the possible-classification-example field with the value financial planning

   3. COG-RunScript-Copy-Possible+Example-financial-planning-to-Classification.bat – In the Index, perform the following steps:
      * Note: When you run the .bat files you will be prompted before each step to press y to continue.

      1. Copy each classification-example field with the value financial planning to the classification field

      2. Copy each possible-classification-example field with value financial planning to the classification field

      3. Remove all of the possible-classification-example fields with value financial planning

COG-RunScript-Remove-Classification=financial-planning.bat can be used to remove the specified values (financial planning in this example) from the classification, classification-example, and possible-classification-example fields, if needed.

Step 5 – Find similar documents and auto classify them

The Shinydocs Cognitive Toolkit is an executable stored with its dependencies, examples, and resources. These are all located in a zip file provided by Shinydocs with the following naming convention: shinydocs-cognitive-toolkit-yyyy-mm-dd (X.X.X).zip.

1. Open a Windows command prompt as Administrator, and then navigate to the child COG Batch Files folder of the Cognitive Toolkit installation folder you created in Step 4 – Modify .bat and .json files

2. Run COG-RunScript-Tag-CS-classification-example-financial-planning.bat to tag similar example documents in the index based on those that were tagged in Step 2 – Tag example documents in Discovery Search

3. Press y to execute the command

4. Next, run COG-Query-FindSimilarClassification-financial-planning.bat to find similar documents using the tagged example documents and the parameters you set in Step 3 – Determine parameters for the .bat and .json files in the Visualizer

5. Press y to execute the command

The Analytics Engine analyzes your data set based on the original documents we tagged as examples of financial planning, and all similar documents are identified and classified as possible financial planning documents based on the text in those documents. Once this process has completed you can view the results in Discovery Search.

Step 6 – View results in Discovery Search

You can quickly view the results in Discovery Search by entering the following query in the search bar: possible-classification-example: “financial planning”.

Review a few of the results by clicking on the links and viewing them in their native application to verify that they are what you are expecting. If they are not, look at the values you set previously — we have found that the following tend to be values to consider refining first:

• Threshold: Is your threshold set too low (or too high)? Typically values below 85–90% may cause misclassification

• Minimum Word Length: Consider increasing this by 1 depending on the initial list of words

• Tokens: Is this value set too high? Try reducing the value by 10% and running your search query. Or, look again at the shape of the Open Clustering visualization — are you including too many words that are not significant for the purposes of similarity? Generally speaking, fewer words to match are better than more words

If you are still having difficulty, look a little closer at your example documents. There may be a stray one included that is causing issues that you are not expecting (for example, a document that is very long and covers many topics may skew your similarity results).

Step 7 – Lock in the results

If you are happy with the results, you can now “lock them in” by copying the temporary values to the classification field (or another field, if applicable).

Copy your results to the classification field

1. Open a Windows command prompt as Administrator, and then navigate to the child COG Batch Files folder of the Cognitive Toolkit installation folder you created in Step 4 – Modify .bat and .json files

2. Run COG-RunScript-Copy-Possible+Example-financial-planning-to-Classification.bat. This command does the following:

   1. Copies your financial planning examples into the classification field

   2. Copies the new possible financial planning examples into the classification field

   3. Removes the possible-classification-example field for examples that equal financial planning

View your results using the Visualizer

You can now view the results on the Classifications Dashboard in the Visualizer. In the example screenshot, there are now 77 files classified as financial planning in addition to what was classified previously.

Step 8 – Cleanup

Assuming you are doing a bunch of these back-to-back, be sure to remove the enrichment tags for the classifications you just applied so that these documents are not used for the next set of documents you are tagging.

1. In Discovery Search, search using enrichmentTags: [your enrichment tag]

2. Turn on Enrichment View and select all of the documents that you want to remove the enrichment tag from

3. Click Remove Tags and check the box on the right

4. Click Save Changes to remove the enrichment tags

Resources

CS - find similar classification folder

The folder of .bat & .json files as described in Step 4 – Modify .bat and .json files.

CS - find similar classification (1).zip

Possible actions for .bat files