## Quick Detection Guide

Spot AI-generated text in seconds

### Visual Scan

- ✗Excessive bullet points (groups of 3)
- ✗Perfect parallel structure
- ✗Em dashes everywhere (2+ per 200 words)
- ✗Uniform paragraph lengths
- ✗Bold headers + emojis

### Phrase Check

Find 2+ of these = likely AI

- ✗ "delve into this topic"
- ✗ "tapestry of experiences"
- ✗ "navigate the landscape"
- ✗ "leverage synergies"
- ✗ "seamlessly integrate"
- ✗ "robust framework"
- ✗ "Here's why:" or "Here's what:"
- ✗ "It's not X. It's Y." (repeated)

### Burstiness

1. Count words in 5 random sentences  
2. Calculate: μ (average) and σ (std dev)  
3. Formula: `B = (σ / μ) × 100`

B < 30 = Likely AI

Example: 24, 23, 26, 25, 24 → B = 4.7

B > 50 = Likely Human

Example: 8, 34, 12, 41, 15 → B = 66.6

### 20-Second Structure Test

Opening  
"In today's rapidly evolving..." = AI

Body  
Every paragraph same length? = AI

Lists  
Groups of exactly 3 items? = AI

Closing  
"What are your thoughts?" = AI

Rhythm  
Metronome vs Jazz? Metronome = AI

Sentences  
All 20-30 words? = AI

## AI Detection Hierarchy

Confidence levels for identifying AI-generated text

### Tier 1: Immediate Red Flags

90-99% AI probability

- Left-in prompt artifacts
- "Certainly, here is a possible introduction..."
- Left-in refusal text
- "I'm sorry, but I don't have access to real-time information"
- Multiple signature words
- "5+ words from signature list"
- 'delve' in academic context
- "We delve into the implications..."
- Perfect triadic repetition
- "5+ instances of groups of 3"

### Tier 2: Strong Indicators

70-90% AI probability

- Low burstiness (B < 20)
- "All sentences 22-28 words"
- Uniform paragraph length
- "Every paragraph 4-5 sentences"
- Em dash frequency
- "5+ per 200 words"
- Setup phrase density
- "3+ 'Here's' or 'The truth is' per 300 words"
- Formulaic structure repetition
- "It's not X, it's Y' used 3+ times"

### Tier 3: Moderate Indicators

40-60% AI probability

- Corporate buzzword density
- "3-5 words like 'leverage,' 'synergy'"
- Consistent Oxford commas
- "Never omitted"
- Question-answer cadence
- "2+ rhetorical Q&A pairs"
- Parallel bullet perfection
- "All bullets identical structure"
- Generic enthusiasm
- "Great question!" 'Excellent point!'

## AI Detection Tools Comparison

Performance metrics for popular AI text detection tools

| Tool | Accuracy | False Positive | Speed | Cost | Notes |
| --- | --- | --- | --- | --- | --- |
| Binoculars | 99% | 1% | Medium | Free | Best accuracy |
| Copyleaks | 94.9% | 5.52% | Fast | $$$ | High accuracy |
| Originality.ai | 92.5% | 4.79% | Fast | $$$ | Combines metrics |
| GPTZero | 89.8% | 5.12% | Fast | $$ | Threshold >85 for human |
| Turnitin | 79% | 2.5% | Slow | $$$$ | Educational standard |
| ZeroGPT | 68.5% | 21% | Fast | $ | High false positive |

### How to Defeat Detection

✓ What Works

- • Paraphrasing (-20% detection)
- • Humanizer Tools (90% effective)
- • Prompt Engineering (87% effective)
- • QuillBot (50% effective)

✗ What Fails

- • Removing Buzzwords (5% effective)
- • Minor Edits (10% effective)
- • Patterns remain structural, not lexical

## Technical Detection Metrics

### Burstiness Formula

Measures sentence length variation, the most reliable structural tell

Formula

B = (σ / μ) × 100

**σ** = Standard deviation

**μ** = Mean sentence length

**B** = Burstiness score

AI Pattern

B = 4.7

Sentences: 24, 23, 26, 25, 24 words

Average: 24.4

Std Dev: 1.14

Low variation = metronome rhythm = AI

Human Pattern

B = 66.6

Sentences: 8, 34, 12, 41, 15 words

Average: 22

Std Dev: 14.66

High variation = jazz rhythm = Human

Threshold: B < 30

Uniform sentence lengths indicate AI generation. Low burstiness reveals algorithmic consistency.

Threshold: B > 50

Natural variation in sentence length indicates human authorship. High burstiness reflects cognitive rhythm.

### Perplexity Score Analysis

How "surprised" a language model is by word choices

Score 5-10

Extremely Predictable

AI-generated (GPT-4, Claude, Gemini)

Score 10-20

Very Predictable

Heavily edited or templated writing

Score 20-50

Normal Variation

Human writing

Score 50+

Unexpected/Creative

Literary fiction, poetry, technical jargon

**Why AI scores low:** Large language models generate the most probable next token. Predictability is the core mechanism. Detection tools like GPTZero use threshold >85 for likely human authorship.