How AI Detection Works
AI text detection is a complex statistical science and not a simple "yes/no" process. At AIChecking, we use advanced linguistic analysis to identify the unique fingerprints left behind by Large Language Models (LLMs) like GPT-4 or Claude.
The Core Metrics
1. Perplexity
Perplexity measures how "surprising" the text is to a language model.
- Low Perplexity: The text is highly predictable and follows standard patterns common in AI outputs.
- High Perplexity: The text is more creative, complex, or unusual, which is a hallmark of human writing.
2. Burstiness
While AI models tend to produce uniform sentence lengths and structures, humans naturally "burst." We might write a long, complex sentence followed by a short, punchy one. High burstiness indicates higher human probability.
3. Perplexity Variance
Human creativity fluctuates. One paragraph might be highly predictable, while the next is full of unique expressions. AIChecking measures how this predictability changes throughout the document. Consistent predictability is a strong signal for AI-generated content.
Is AI Detection 100% Accurate?
No. AI detection is probabilistic. Think of it like a weather forecast rather than a physical measurement. Factors like specific academic formatting, non-native English writing styles, or heavy editing can influence the results.
Best Practices
We recommend using AIChecking as a tool for initial screening and human review. Higher confidence scores (above 85%) are generally very reliable, but results in the "Uncertain" zone (30% - 70%) require closer investigation.