BLEU struggles with word order and synonyms. Always pair with human review for final PDF deliverables.
Page boundaries are arbitrary for BLEU. Concatenate all extracted text from the PDF into a single string, then segment by punctuation. This avoids penalizing valid line breaks. bleu+pdf+work
| Tool | Best for | Handling of BLEU-sensitive elements | |------|----------|--------------------------------------| | (Export to Word) | Small documents with complex layouts | Good for columns, poor for hyphenation | | pdfplumber (Python) | Programmatic, multilingual text | Excellent; can detect line breaks and table structures | | Tesseract + OCR (for scanned PDFs) | Image-based PDFs | Required but introduces OCR errors | | Grobid | Scientific papers (double columns) | Superior for multi-column text ordering | BLEU struggles with word order and synonyms
Use sacrebleu for consistent, reproducible scoring: Concatenate all extracted text from the PDF into
: For evaluating and improving machine translation systems, ensuring that translations are accurate and natural-sounding.
A researcher wants to compare three MT engines (Google, Microsoft, Amazon) for translating a 50-page PDF research paper from Chinese to English.
Compare text extracted from a PDF (candidate text) against a reference text (human translation or ground truth) to determine quality.