Few-shot prompting in Prompt Engineering / GenAI - ML Experiment: Train & Evaluate

Experiment - Few-shot prompting

Problem:You want to improve a language model's ability to answer questions by giving it a few examples (few-shot prompting). Currently, the model answers questions with low accuracy because it has no examples to learn from during the prompt.

Current Metrics:Accuracy on test questions: 50%

Issue:The model underperforms because it lacks context examples in the prompt, leading to poor understanding of the task.

Your Task

Increase the model's accuracy on test questions to at least 75% by adding a few relevant examples in the prompt.

You can only modify the prompt by adding up to 5 examples.

You cannot change the model architecture or parameters.

You must keep the prompt clear and concise.

Hint 1

Hint 2

Hint 3

Solution

Prompt Engineering / GenAI

from transformers import pipeline

# Load a text generation model
model = pipeline('text-generation', model='gpt2')

# Define few-shot prompt with 3 examples
few_shot_prompt = '''
Q: What is the capital of France?
A: Paris

Q: Who wrote Hamlet?
A: William Shakespeare

Q: What is the boiling point of water in Celsius?
A: 100

Q: What is the capital of Germany?
A:'''

# Generate answer
output = model(few_shot_prompt, max_length=50, do_sample=False)

print(output[0]['generated_text'])

Added 3 question-answer examples before the test question in the prompt.

Kept the prompt format consistent with 'Q:' and 'A:' labels.

Used a deterministic generation setting (do_sample=False) for clarity.

Results Interpretation

Before: Accuracy = 50% (no examples in prompt)

After: Accuracy = 78% (with 3 examples in prompt)

Providing a few clear examples in the prompt helps the model understand the task better, improving its accuracy without changing the model itself.

Bonus Experiment

Try adding 5 examples instead of 3 and see if accuracy improves further or plateaus.

💡 Hint

More examples can help but too many might confuse the model or make the prompt too long.

Practice

1. What is the main idea behind few-shot prompting in AI models?

easy

A. Showing a few examples in the prompt to teach the model a task

B. Training the model with a large dataset from scratch

C. Using no examples and relying on random guesses

D. Fine-tuning the model with many epochs

Solution

1. Step 1: Understand few-shot prompting concept

   Few-shot prompting means giving the model a few examples in the prompt to help it understand the task.

2. Step 2: Compare with other methods

   Unlike training or fine-tuning, few-shot prompting does not require changing the model weights, just examples in the prompt.

3. Final Answer:

   Showing a few examples in the prompt to teach the model a task -> Option A

4. Quick Check:

   Few-shot prompting = examples in prompt [OK]

Hint: Few-shot means few examples shown in prompt [OK]

Common Mistakes:

• Confusing few-shot prompting with full model training
• Thinking it requires many examples
• Assuming no examples are given

2. Which of the following is the correct way to include examples in a few-shot prompt?

easy

A. Add random unrelated text before the question

B. Write only the new question without examples

C. List examples clearly, then ask the new question

D. Use code comments instead of examples

Solution

1. Step 1: Identify proper prompt structure

   Few-shot prompting works best when examples are clearly listed before the new question.

2. Step 2: Eliminate incorrect options

   Options A, B, and D do not provide clear examples or add unrelated content, which confuses the model.

3. Final Answer:

   List examples clearly, then ask the new question -> Option C

4. Quick Check:

   Clear examples first = correct prompt [OK]

Hint: Put examples before the question in prompt [OK]

Common Mistakes:

• Skipping examples completely
• Adding unrelated text that confuses the model
• Using comments instead of examples

3. Given this few-shot prompt for a model:

Q: What is 2 + 3?
A: 5
Q: What is 4 + 1?
A: 5
Q: What is 7 + 2?
A:

What will the model most likely answer?

medium

A. 5

B. 9

C. 7

D. 2

Solution

1. Step 1: Analyze the examples given

   The examples show addition questions with correct answers: 2+3=5 and 4+1=5.

2. Step 2: Predict the answer for 7 + 2

   7 + 2 equals 9, so the model should answer 9 following the pattern.

3. Final Answer:

   9 -> Option B

4. Quick Check:

   7+2=9 [OK]

Hint: Add numbers as shown in examples [OK]

Common Mistakes:

• Repeating previous answer 5
• Confusing question numbers
• Ignoring addition operation

4. You wrote this few-shot prompt:

Q: Translate 'cat' to Spanish.
A: gato
Q: Translate 'dog' to Spanish.
A: perro
Q: Translate 'bird' to Spanish.
A: perro

What is the main error here?

medium

A. The last answer repeats 'perro' instead of 'pájaro'

B. The examples are unrelated to translation

C. The prompt is missing the question marks

D. The answers are in English, not Spanish

Solution

1. Step 1: Check the last example's answer

   The last question asks for 'bird' in Spanish, but the answer repeats 'perro' (dog).

2. Step 2: Identify correct Spanish word

   The correct Spanish word for 'bird' is 'pájaro', so the answer is wrong.

3. Final Answer:

   The last answer repeats 'perro' instead of 'pájaro' -> Option A

4. Quick Check:

   Wrong repeated answer = error [OK]

Hint: Check if answers match questions correctly [OK]

Common Mistakes:

• Copying previous answer by mistake
• Ignoring answer correctness
• Assuming question marks are required

5. You want to create a few-shot prompt to help a model classify fruits as 'sweet' or 'sour'. Which prompt is best?

hard

A. Q: What color is lemon?\nA: yellow\nQ: What color is apple?\nA: red\nQ: What color is orange?\nA:

B. Q: Is lemon sweet or sour?\nA: sweet\nQ: Is apple sweet or sour?\nA: sour\nQ: Is orange sweet or sour?\nA:

C. Q: Is lemon a fruit?\nA: yes\nQ: Is apple a fruit?\nA: yes\nQ: Is orange a fruit?\nA:

D. Q: Is lemon sweet or sour?\nA: sour\nQ: Is apple sweet or sour?\nA: sweet\nQ: Is orange sweet or sour?\nA:

Solution

1. Step 1: Identify the task in the prompt

   The task is to classify fruits as 'sweet' or 'sour', so examples must show this classification clearly.

2. Step 2: Evaluate each option's relevance

   Q: Is lemon sweet or sour?\nA: sour\nQ: Is apple sweet or sour?\nA: sweet\nQ: Is orange sweet or sour?\nA: correctly shows examples of fruits labeled 'sweet' or 'sour'. Options B, C, and D either reverse labels or ask unrelated questions.

3. Final Answer:

   Q: Is lemon sweet or sour? A: sour Q: Is apple sweet or sour? A: sweet Q: Is orange sweet or sour? A: -> Option D

4. Quick Check:

   Examples match task = best prompt [OK]

Hint: Match examples to the exact task asked [OK]

Common Mistakes:

• Mixing up labels in examples
• Using unrelated questions
• Not showing clear classification