# Presentation slides

<div id="bkmrk-%F0%9F%93%8A-doceng-2026-confer"><div>### 📊 DocEng 2026 Conference Presentation Deck

Official 10-slide presentation delivered at ACM DocEng 2026 (28.08.2026).

 </div><div> [ 📥 Download PDF ](https://wiki.stergios.ch/attachments/22) [ 📥 Download PPTX ](https://wiki.stergios.ch/attachments/23) </div></div>## Slide Deck &amp; Presentation Breakdown

<div id="bkmrk-slide-1%3A-title-%26-aut"><div>### Slide 1: Title &amp; Authors

 <span>Slide 01 / 10</span> </div><div style="text-align:center;"> [ ![Slide 1: Title & Authors](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-01.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-01.png "Click to inspect slide 1 in high resolution") </div> **Speaker Note:** Cost-Aware Human-LLM Collaboration for Post-OCR Corrections in Swiss Historical Newspapers (DocEng 2026, 28.08.2026). Presented by Stergios Konstantinidis, Hayman Lotfy, Prof. Michalis Vlachos.

</div><div id="bkmrk-slide-2%3A-motivation-"><div>### Slide 2: Motivation &amp; Archival Scale

 <span>Slide 02 / 10</span> </div><div style="text-align:center;"> [ ![Slide 2: Motivation & Archival Scale](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-02.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-02.png "Click to inspect slide 2 in high resolution") </div> **Speaker Note:** Building RAG systems for historical archives across 300+ years of newspapers, millions of pages, and 12 TB of raw high-resolution scan imagery.

</div><div id="bkmrk-slide-3%3A-why-documen"><div>### Slide 3: Why Document Cleaning is Not Straightforward

 <span>Slide 03 / 10</span> </div><div style="text-align:center;"> [ ![Slide 3: Why Document Cleaning is Not Straightforward](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-03.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-03.png "Click to inspect slide 3 in high resolution") </div> **Speaker Note:** Post-OCR correction is essential for downstream retrieval, but traditional tools neglect historical linguistic shifts and archaic orthography.

</div><div id="bkmrk-slide-4%3A-heterogeneo"><div>### Slide 4: Heterogeneous Segment Utility

 <span>Slide 04 / 10</span> </div><div style="text-align:center;"> [ ![Slide 4: Heterogeneous Segment Utility](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-04.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-04.png "Click to inspect slide 4 in high resolution") </div> **Speaker Note:** Different segments benefit very differently: Segment D gains +2.0% CER improvement with zero overcorrections, while Segment B suffers -3.0% CER degradation due to 10 overcorrections!

</div><div id="bkmrk-slide-5%3A-optimal-cor"><div>### Slide 5: Optimal Correction Prioritization

 <span>Slide 05 / 10</span> </div><div style="text-align:center;"> [ ![Slide 5: Optimal Correction Prioritization](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-05.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-05.png "Click to inspect slide 5 in high resolution") </div> **Speaker Note:** Theoretical premise: What if we knew in advance which archival documents would benefit most from LLM correction?

</div><div id="bkmrk-slide-6%3A-the-real-wo"><div>### Slide 6: The Real-World Dilemma

 <span>Slide 06 / 10</span> </div><div style="text-align:center;"> [ ![Slide 6: The Real-World Dilemma](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-06.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-06.png "Click to inspect slide 6 in high resolution") </div> **Speaker Note:** In reality, ground truth is unavailable. Naively correcting all documents produces unpredictable degradation and wastes massive token budgets.

</div><div id="bkmrk-slide-7%3A-our-contrib"><div>### Slide 7: Our Contribution - Intelligent Routing Architecture

 <span>Slide 07 / 10</span> </div><div style="text-align:center;"> [ ![Slide 7: Our Contribution - Intelligent Routing Architecture](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-07.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-07.png "Click to inspect slide 7 in high resolution") </div> **Speaker Note:** A machine-learned Router evaluating expected CER benefit: If LLM is sufficient -&gt; route to LLM; if degradation is too severe -&gt; route to human review (&lt;5%); otherwise leave the segment untouched.

</div><div id="bkmrk-slide-8%3A-experimenta"><div>### Slide 8: Experimental Evaluation &amp; Benchmark Curves

 <span>Slide 08 / 10</span> </div><div style="text-align:center;"> [ ![Slide 8: Experimental Evaluation & Benchmark Curves](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-08.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-08.png "Click to inspect slide 8 in high resolution") </div> **Speaker Note:** Empirical results comparing baseline OCR, All-LLM, ConfBERT, and our Cost-Aware Routing framework across historical Swiss periodicals.

</div><div id="bkmrk-slide-9%3A-key-takeawa"><div>### Slide 9: Key Takeaways &amp; Research Streams

 <span>Slide 09 / 10</span> </div><div style="text-align:center;"> [ ![Slide 9: Key Takeaways & Research Streams](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-09.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-09.png "Click to inspect slide 9 in high resolution") </div> **Speaker Note:** Key contributions: 40% reduction in correction effort, negligible setup cost, and an effective human guardrail identifying segments requiring expert archivist attention.

</div><div id="bkmrk-slide-10%3A-conclusion"><div>### Slide 10: Conclusion &amp; Contact

 <span>Slide 10 / 10</span> </div><div style="text-align:center;"> [ ![Slide 10: Conclusion & Contact](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-10.png) ](https://wiki.stergios.ch/uploads/images/gallery/2026-09/doceng-slide-10.png "Click to inspect slide 10 in high resolution") </div> **Speaker Note:** Wrap-up, open questions, and research collaboration contact information at UNIL-DESI.

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