{"entity":{"id":"ablation-study","kind":"term","name":"Ablation study and multi-task heads","aka":["ablation study","ablation studies","ablation","leave-one-modality-out","multi-task learning","multi-task heads","task heads","specialised task heads","shared backbone"],"tldr":"An ablation removes one component or modality at a time and re-measures performance, which is the only way to know what each part contributes; multi-task heads let one shared backbone serve several outputs.","summary":"In machine learning, ablation is the removal of a component to determine its contribution to the system (Wikipedia). For a multimodal cancer model the ablation is per modality: drop mutations, copy number, protein or the pretrained encoder and see whether survival or drug-response accuracy moves. Multi-task learning solves several tasks at once through a shared representation with task-specific heads (Wikipedia), which is efficient but can let one easy task (cancer type) dominate the backbone.","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Ablation_(artificial_intelligence)","links":[{"label":"Wikipedia: multi-task learning","url":"https://en.wikipedia.org/wiki/Multi-task_learning"},{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Ablation_(artificial_intelligence)"}],"tags":["cansim-terms"],"related":["cancer-ai-vocabulary"],"cancers":[],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["multimodal-fusion","accuracy-f1","mechanism-of-action-recovery"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Listed in the CanSim terms map 1.0.0 (docs/onco/terms.json, generated 2026-09-24), CC BY 4.0, attribution: CanSim project, an open, public-data-first cancer foundation-model programme; CanSim page path /terms/ablation-study."],"provenance":{"editedBy":"OnCo CanSim terms wave (Wikipedia summaries, standards and project pages, GDC and FDA pages, Europe PMC)","editedOn":"2026-09-24","note":"CanSim terms map 1.0.0 (docs/onco/terms.json, generated 2026-09-24), CC BY 4.0, attribution: CanSim project, an open, public-data-first cancer foundation-model programme"},"category":"Methods and models"},"route":"/terms/ablation-study/","neighbours":{"term":[{"id":"accuracy-f1","kind":"term","name":"Accuracy, macro-F1 and confusion matrices","route":"/terms/accuracy-f1/"},{"id":"cancer-ai-vocabulary","kind":"term","name":"Cancer AI vocabulary (CanSim terms map)","route":"/terms/cancer-ai-vocabulary/"},{"id":"mechanism-of-action-recovery","kind":"term","name":"Mechanism-of-action recovery and known-biology probes","route":"/terms/mechanism-of-action-recovery/"},{"id":"multimodal-fusion","kind":"term","name":"Multimodal fusion (early, late, modality dropout)","route":"/terms/multimodal-fusion/"}]}}