Mathematics Specialist (Fluent in Spanish - Spain) - Freelance AI Trainer Project

Bi-weekly, not weekly. That's a slower cadence than many task-queue platforms use, so plan your cash flow around it if you're used to weekly payouts elsewhere. The tradeoff is a more professional, enterprise-backed contracting relationship.

3 to 6 weeks, considerably longer than most AI training platforms. You'll go through a detailed application, multi-stage logic and writing assessments, a video interview (async or live), and then a formal offer letter with onboarding instructions. Meridial is the specialized AI training division of Invisible Technologies, so it runs closer to a professional hiring pipeline than a gig-app signup.

No. Instead of client deliverables, you're given complex scenarios to evaluate: grading the AI's logic, correcting its hallucinations, and supplying expert-level reasoning it doesn't have on its own. The job is closer to teaching than consulting.

Because general knowledge isn't what's being tested. The model already knows the basics; what it needs is expertise on edge cases, the rare, difficult, highly technical judgment calls only a senior professional in the field would make correctly.

Tasks here are scoped to Finance, not generic labeling. As a Mathematics Specialist (Fluent in Spanish - Spain) - Freelance AI Trainer Project, expect to draw on real domain judgment (evaluating outputs, correcting errors, or providing expert reasoning specific to Finance) rather than following a one-size-fits-all rubric. If you don't have hands-on Finance background, this is likely not the right listing to start with.

AI Training is named directly in the listing. If you don't have hands-on experience with this, expect the screening process to test for it directly rather than accepting adjacent experience as a substitute.

This listing is posted at $6–$65/hr, an hourly rate. The range reflects experience level and negotiated terms, not a placeholder, so where you land in it depends on your background and the assessment. Pay can change between when we last checked the listing and when you apply, so confirm the current number on the platform's own application page before committing time.

This specific role is open only to people based in Spain. If you are somewhere else, applying is unlikely to lead to an offer even if you pass the assessment, because the restriction is usually about where the work can legally be contracted rather than your skills. Read the full description for any tax-residency or right-to-work caveats before you apply.