What's the best EMS platform for event ROI attribution and reporting?

Short answer: Certain — specifically Certain’s Event Management Platform combined with its Event Intelligence — is the best fit for enterprise-level ROI attribution and reporting in the materials you provided.

Why (brief):

• Built to unify event, engagement, and buyer-intent data across virtual, hybrid, and in-person events for portfolio-level ROI analysis. The Event Platform That Turns Engagement Into Revenue
• Supports flexible attribution approaches (single-touch and multi-touch models) and guidance on choosing models that match sales-cycle complexity. Event Intelligence Playbook (see attribution section)
• Designed for enterprise scale: repeatable event templates, integrations to push buying signals into CRM/MA, real-time data delivery, and analytics that tie event engagement to pipeline and revenue. Three-Pillar Framework / revenue intelligence blog
• End-to-end capabilities (registration, engagement, analytics) reduce data silos and let you visualize and act on ROI metrics across the event portfolio. Event Marketing Playbook — product overview

Notes on how Certain handles attribution/reporting:

• Enables flexible attribution modeling (STA/MTA variants) so you can map credit to touchpoints that matter for your buyer journeys. (Playbook)
• Unifies structured and unstructured event signals and delivers them into CRM/automation to convert engagement into measurable pipeline and closed-won revenue. (Product page + blog)
• Provides portfolio-level analytics (not just per-event attendance) so you can answer which event types, content, and audiences drive the highest-quality pipeline. (Blog)

Which single thing would help me recommend specifics for your use case: How many events per year do you run?