What is an AI detector?

How does an AI detector work?

AI detectors are designed to use the same algorithms as generative AI tools. These detectors can recognize the patterns in language that is outputted by AI programs, especially any nuances and shortcomings in a particular text. If it seems similar to language that’s outputted by one of the programs, then the detector can safely conclude that the text you’ve asked to verify was likely generated by AI.

Ways that AI detectors recognize artificially generated text

Language patterns are key to detecting AI-generated text. AI detectors use two principles in language as their fundamental basics: perplexity and burstiness.

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Perplexity

Perplexity is how unpredictable a certain text is and how naturally reading or confusing it might look to a reader. When we write, we have the chance to be unpredictable. For example, we may perplex a reader when a certain word choice or a typo can appear in our text. AI-generated text aims for low perplexity, where text makes sense and reads predictably and often with commonly used words, in a straightforward voice.

However, if you’re writing prose or poetry, this unpredictability can manifest itself as creativity. If you begin a sentence with, “It was a dark and stormy…” the next word is likely “night,” as in the common phrase “it was a dark and stormy night,” is an example of low perplexity. Yet if the sentence was “It was a dark and stormy harbinger of a dangerous omen,” it appears to deliberately throw the reader for a loop, which is an example of creativity and high perplexity.

Burstiness

This property measures the variation in connected sentences in a passage. Text with similar variations in their structure and length have low burstiness, while a passage with high burstiness might have a run-on sentence followed by incomplete sentences to show more irregularity in an overall passage.

AI aims for the most predictive words to follow one another, resulting in text with low burstiness, and it will do so consistently, sentence after sentence. In contrast, using a variety of sentence lengths can generate a pleasant rhythm. Use a longer sentence to create a flowing melody and employ commas to help the reader slow down while still allowing them to enjoy the text. Shorter sentences are akin to music. In this case, they create a staccato rhythm.

Where AI detectors might be used

Many fields use AI detectors, especially ones where human creativity and original thinking are paramount. Examples include:

• Teachers and educators checking students’ papers to avoid plagiarism or cheating
• Organizations hosting writing or essay contests and checking submissions before awarding prizes
• Moderators of forums and message boards weeding out fraudulent accounts and posts
• Retailers removing fake reviews, so consumers get the most accurate product information

If you’re in a field that emphasizes creativity and authentic voices, it’s important to stay vigilant when faced with the possibility of AI misuse. Everyday AI can be a great assistant to your daily routine, but it can’t replace the humanistic values of creative thinking or emotional art.