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Classification

Classification is the most flexible labeling work type for evaluating, comparing, or categorizing data. Experts answer predefined questions about images, videos, text, or audio — without drawing or annotating on the data itself. Assign one or more labels from a fixed set to your data — e.g., “cat”, “blurry”, “positive sentiment”. Unlike annotation-based work types, Classification captures structured responses to questions you define.

Ideal for: High-level categorization, quality assessment, content moderation, and multi-input comparisons.

When to Use

Task Type Examples
Single-Input Tasks “Is there a car in this image?”
“Is this video blurry or clear?”
“What language is being spoken?”
“Is this email spam or not?”
Multi-Input Tasks “Which landing page looks better?” (compare 2 images)
“Does this audio match the video?” (image + audio)
“What is the correct output?” (code + result comparison)
Subjective Judgments Quality assessment, sentiment analysis, content appropriateness, preference ranking

When to Use Other Work Types

Supported Data Types

  • Image, Video, Audio, Text - Single or multiple inputs per task
  • Mixed Media - Combine different data types in one task

Key Features

Custom UI Builder (ATGL) - Design tailored interfaces for your specific needs:

  • Display multiple videos side-by-side
  • Overlay audio with transcript panels
  • Present code snippets with output regions

Consensus Labeling - Have 3-7 experts independently label each task. The system uses majority voting to determine the final result.

  • Higher accuracy for subjective tasks
  • Reduces individual bias
  • Provides confidence scores

Example Scenarios

Input Type Question Example
Image “Is this photo clear enough for the website?”
Audio “Is the speaker’s accent native?”
Text “Does this express positive sentiment?”
Image Pair “Which design is more appealing?”
Image + Audio “Does the sound match this scene?”

Classification Types

  • Single-label - One category per item
  • Multi-label - Multiple categories per item
  • Binary - Yes/No decisions
  • Hierarchical - Nested categories
  • Comparative - Rank or compare items

Getting Started

  1. Define your classification categories and questions
  2. Configure custom UI layouts if needed (optional)
  3. Enable consensus for multiple expert opinions (optional)
  4. Prepare your input data
  5. Submit batches via API
  6. Track progress and download results

How to Submit Batches

Indirect Demand (CSV File) - Best for large-scale projects with thousands of items.

📖 View API Documentation →

Direct Demand (Inline Data) - Best for dynamic tasks or real-time processing.

📖 View API Documentation →

Best Practices

  1. Clear Questions - Make questions unambiguous and mutually exclusive
  2. Provide Context - Include relevant metadata for better decisions
  3. Use Consensus - Enable for subjective or opinion-based tasks
  4. Custom Layouts - Leverage ATGL for complex multi-input scenarios
  5. Quality Guidelines - Document edge cases and ambiguous scenarios

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