Few-shot and zero-shot learning are two key approaches in modern artificial intelligence that enable models to learn with minimal amounts of data. While few-shot learning uses a few examples, zero-shot learning can solve tasks without any prior demonstration.
What is Zero-shot and Few-shot Learning¶
Zero-shot and few-shot learning represent two key approaches to utilizing large language models (LLMs) without the need for further training. While zero-shot learning relies solely on the model’s natural ability to understand instructions, few-shot learning provides the model with several examples for better understanding of the required task.
Zero-shot Learning: Without Examples¶
Zero-shot learning uses only a clearly formulated prompt without any demonstration examples. The model relies on its pre-trained knowledge and ability to understand instructions in natural language.
# Zero-shot example for sentiment classification
prompt = """
Analyze the sentiment of the following sentence and respond only with 'positive', 'negative', or 'neutral':
Sentence: "This product is absolutely amazing, I recommend it to everyone!"
Sentiment:
"""
Advantages of zero-shot approach include implementation simplicity, response speed, and minimal token consumption. On the other hand, it may be less accurate for more complex or specific tasks.
Few-shot Learning: Learning from Examples¶
Few-shot learning provides the model with several demonstration examples (typically 1-10) directly in the prompt. This approach utilizes the in-context learning capabilities of modern LLMs.
# Few-shot example for the same task
prompt = """
Analyze the sentiment of the following sentences:
Sentence: "I love this app, it's perfect!"
Sentiment: positive
Sentence: "Unfortunately, it disappointed me, doesn't work as it should."
Sentiment: negative
Sentence: "It's okay, nothing special."
Sentiment: neutral
Sentence: "This product is absolutely amazing, I recommend it to everyone!"
Sentiment:
"""
Practical Performance Comparison¶
To demonstrate the differences, we tested both approaches on the task of extracting structured data from text. The results show significant differences in accuracy and consistency.
Zero-shot Implementation¶
import openai
def zero_shot_extraction(text):
prompt = f"""
Extract name, email, and phone from the following text in JSON format:
Text: {text}
JSON:
"""
response = openai.ChatCompletion.create(
model="gpt-3.5-turbo",
messages=[{"role": "user", "content": prompt}],
temperature=0
)
return response.choices[0].message.content
Few-shot Implementation¶
def few_shot_extraction(text):
examples = """
Text: "Contact me at [email protected] or call 776 123 456"
JSON: {"name": "Jane Doe", "email": "[email protected]", "phone": "776 123 456"}
Text: "Peter Smith, tel: +420 602 987 654, [email protected]"
JSON: {"name": "Peter Smith", "email": "[email protected]", "phone": "+420 602 987 654"}
Text: "Write to me at [email protected]"
JSON: {"name": null, "email": "[email protected]", "phone": null}
"""
prompt = f"""
Extract name, email, and phone from text in JSON format:
{examples}
Text: {text}
JSON:
"""
response = openai.ChatCompletion.create(
model="gpt-3.5-turbo",
messages=[{"role": "user", "content": prompt}],
temperature=0
)
return response.choices[0].message.content
When to Use Which Approach¶
Zero-shot is ideal for:¶
- Simple, well-defined tasks (translation, summarization)
- Situations with limited context or token count
- Rapid prototyping and experiments
- Tasks where the model already shows good performance
Prefer few-shot for:¶
- Complex or domain-specific tasks
- Situations requiring specific output format
- Tasks with ambiguous rules
- Cases where you need high result consistency
Few-shot Prompt Optimization¶
For maximum few-shot learning efficiency, careful example design is key. Examples should cover various scenarios and edge cases that may appear in production data.
# Well-designed few-shot examples for classification
examples = [
{
"input": "Fast delivery, quality packaging, satisfied customer!",
"output": "positive",
"note": "clearly positive"
},
{
"input": "Slow delivery, damaged package, refund requested.",
"output": "negative",
"note": "clearly negative"
},
{
"input": "Average quality for standard price.",
"output": "neutral",
"note": "neutral evaluation"
},
{
"input": "Great product, but too expensive for me.",
"output": "mixed",
"note": "contains both positive and negative aspects"
}
]
Performance Measurement and Monitoring¶
For production deployment, it’s crucial to implement systematic performance measurement of both approaches. We recommend A/B testing with metrics relevant to the specific use case.
class PromptEvaluator:
def __init__(self):
self.metrics = {
'accuracy': [],
'response_time': [],
'token_usage': [],
'cost': []
}
def evaluate_approach(self, test_cases, approach_func):
results = []
for case in test_cases:
start_time = time.time()
try:
response = approach_func(case['input'])
accuracy = self.calculate_accuracy(response, case['expected'])
response_time = time.time() - start_time
results.append({
'accuracy': accuracy,
'response_time': response_time,
'success': True
})
except Exception as e:
results.append({
'accuracy': 0,
'response_time': time.time() - start_time,
'success': False,
'error': str(e)
})
return self.aggregate_results(results)
Cost-Benefit Analysis¶
Few-shot learning typically consumes 2-5x more tokens than zero-shot, which directly translates to costs. It’s important to evaluate whether increased accuracy justifies higher costs for the specific application.
Summary¶
Zero-shot and few-shot learning represent complementary approaches to utilizing LLMs. Zero-shot offers speed and efficiency for standard tasks, while few-shot provides higher accuracy and control for complex scenarios. The choice between them depends on specific project requirements, available resources, and required output quality. In production environments, we recommend systematic testing of both approaches with clearly defined success metrics.