Understanding Confidence Scores

What Are Confidence Scores?

Every extracted instrument includes a confidence score between 0.0 and 1.0. This combines two factors:

1. Vision confidence — how clearly the AI could read the tag from the drawing
2. Classification confidence — how certain the ISA 5.1 mapping is

Color Coding

In the review interface and Excel export:

• Green (0.7+) — High confidence. Likely correct. Quick scan is usually sufficient.
• Yellow (0.5-0.7) — Medium confidence. Worth checking. The AI read something but isn't fully certain.
• Red (below 0.5) — Low confidence. Needs review. The tag may be misread, truncated, or from a non-standard symbol.

Common Causes of Low Confidence

• Poor scan quality — blurry or low-DPI images make small text hard to read
• Non-standard symbols — company-specific instrument symbols not in ISA 5.1
• Overlapping text — annotations covering instrument bubbles
• Unusual tag formats — non-ISA naming conventions
• Truncated codes — AI read "TI" when the drawing actually shows "TIC"

Review Strategy

For efficient review, focus on:

1. Red items first — these have the highest chance of errors
2. Yellow items — spot-check a few to gauge overall accuracy
3. Green items — scan quickly for obvious mistakes, but these are usually correct
4. Signal class "REVIEW" — these are indicators/gauges that may or may not need I/O points