Overview 🔍

After uploading your files, BDIViz launches its main interface, allowing you to visually explore match candidates between your source dataset and the target schema.

Interactive Heatmap 🔥

The heatmap is the primary visualization tool in BDIViz. Each cell represents a match candidate between a source attribute (y-axis) and a target attribute (x-axis).

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Key Features

Each cell corresponds to a potential match:

  • Color intensity indicates similarity score (darker = stronger match).
  • Green = accepted match, Red = rejected match.
  • Click on a cell to inspect match details.

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The x-axis displays the target schema’s structure as a semantic hierarchy:

  • Category Level: e.g., clinical, biospecimen
  • Node Level: e.g., diagnosis, treatment
  • Leaf Nodes: individual target attributes

Color and curved connectors help clarify relationships and improve navigation.

Clicking a heatmap node reveals a stacked histogram panel:

  • Top Chart: Source column value distribution
  • Bottom Chart: Target column value distribution

Use this to evaluate whether the two columns share meaningful overlap.

Tip: Similar distributions (e.g., shared categories like “Male” and “Female”) often suggest semantic alignment.

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The top-level filter tabs help narrow your focus:

  • All: View all candidate matches
  • Accepted: Only show confirmed matches
  • Unmatched: Only show source columns with no confirmed match
  • Expand on Hover: Toggle whether expanded histograms appear on hover or click

Filters and Search Controls 🔍

Fine-tune the heatmap view using a suite of filters:

Select a specific source column to examine.

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Dropdown key:

  • Green: Already matched
  • Grey: Manually discarded
  • All: Show all source attributes

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Set a minimum similarity score for visible candidates. Range: 0.0 – 1.0.

  • 0.0: Show all matches
  • 1.0: Show only perfect matches

Controls how many similar source attributes appear on the heatmap when a single source column is selected.

Note: Only applies when Source Attribute ≠ “All”.

Quickly locate and highlight target attributes by name or keyword.

Lower Panel: Match Details 🔎

Clicking on any heatmap node reveals deeper insights below:

value-comparisons

Visualizes string-based fuzzy matching between source and target values.

  • Each row: one source value + its closest matches
  • Use to validate whether mapping is semantically and syntactically justified

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Visualizes how different matchers contributed to the candidate match score.

  • Each row: a matcher
  • Each column: a candidate
  • Dots indicate support from that matcher

What’s Next? 🚀

After reviewing the matches:

  • Accept or reject individual match suggestions
  • Use filtering to prioritize high-confidence matches
  • Proceed to export, refine, or apply your matched schema for downstream harmonization tasks