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Retrieval strategies (similarity, MMR, hybrid) in Agentic AI - Interactive Code Practice

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Practice - 5 Tasks
Answer the questions below
1fill in blank
easy

Complete the code to compute cosine similarity between query and documents.

Agentic AI
similarity_scores = cosine_similarity(query_vector, [1])
Drag options to blanks, or click blank then click option'
Aempty_vectors
Bquery_vector
Crandom_vectors
Ddocument_vectors
Attempts:
3 left
💡 Hint
Common Mistakes
Using the query vector instead of document vectors for comparison.
2fill in blank
medium

Complete the code to select top k documents based on similarity scores.

Agentic AI
top_k_indices = similarity_scores.argsort()[::-1][:[1]]
Drag options to blanks, or click blank then click option'
A0
Bn
Ck
Dlen
Attempts:
3 left
💡 Hint
Common Mistakes
Using 0 or len instead of k for slicing.
3fill in blank
hard

Fix the error in the Maximal Marginal Relevance (MMR) score calculation.

Agentic AI
mmr_score = lambda doc, selected: lambda_param * similarity(doc, query) - (1 - lambda_param) * max(similarity(doc, s) for s in [1])
Drag options to blanks, or click blank then click option'
Aselected
Bquery
Call_docs
Ddocuments
Attempts:
3 left
💡 Hint
Common Mistakes
Using the query or all documents instead of selected documents for redundancy check.
4fill in blank
hard

Fill both blanks to implement a hybrid retrieval score combining similarity and MMR.

Agentic AI
hybrid_score = lambda doc, selected: alpha * similarity(doc, query) + (1 - alpha) * [1](doc, selected)
selected_doc = max(candidates, key=lambda doc: [2](doc, selected))
Drag options to blanks, or click blank then click option'
Ammr_score
Bsimilarity
Chybrid_score
Dredundancy_score
Attempts:
3 left
💡 Hint
Common Mistakes
Using similarity instead of mmr_score for the first blank.
Using similarity instead of hybrid_score for selection.
5fill in blank
hard

Fill all three blanks to create a dictionary of document scores filtered by a threshold.

Agentic AI
filtered_scores = {doc: [1] for doc, score in scores.items() if score [2] [3]
Drag options to blanks, or click blank then click option'
Ascore
B>
Cthreshold
Ddoc
Attempts:
3 left
💡 Hint
Common Mistakes
Using doc instead of score as dictionary value.
Using '<' instead of '>' for filtering.

Practice

(1/5)
1. Which retrieval strategy focuses on ranking results purely based on how close they are to the query?
easy
A. Random retrieval
B. Maximal Marginal Relevance (MMR)
C. Similarity-based retrieval
D. Hybrid retrieval

Solution

  1. Step 1: Understand similarity-based retrieval

    Similarity-based retrieval ranks results by how close or similar they are to the query, focusing only on relevance.
  2. Step 2: Compare with other strategies

    MMR balances relevance and diversity, hybrid combines methods, and random is unrelated.
  3. Final Answer:

    Similarity-based retrieval -> Option C
  4. Quick Check:

    Similarity = closeness only [OK]
Hint: Similarity means closest match only [OK]
Common Mistakes:
  • Confusing MMR with similarity
  • Thinking hybrid is only similarity
  • Choosing random as a valid strategy
2. Which of the following is the correct way to describe Maximal Marginal Relevance (MMR)?
easy
A. Combines all retrieval methods without weighting
B. Ranks results by random selection
C. Only uses keyword matching
D. Balances relevance and diversity in retrieval

Solution

  1. Step 1: Define MMR

    MMR is designed to balance relevance to the query and diversity among the results to avoid redundancy.
  2. Step 2: Eliminate incorrect options

    Random selection is unrelated, keyword matching is too narrow, and combining without weighting is not MMR.
  3. Final Answer:

    Balances relevance and diversity in retrieval -> Option D
  4. Quick Check:

    MMR = relevance + diversity [OK]
Hint: MMR mixes relevance with diversity [OK]
Common Mistakes:
  • Thinking MMR is random
  • Assuming MMR uses only keywords
  • Believing MMR combines methods blindly
3. Given the following pseudo-code for a hybrid retrieval method combining similarity and MMR scores:
results = []
for doc in documents:
    sim_score = similarity(query, doc)
    mmr_score = mmr(query, doc, results)
    combined_score = 0.6 * sim_score + 0.4 * mmr_score
    results.append((doc, combined_score))
results.sort(key=lambda x: x[1], reverse=True)
print([doc for doc, score in results[:3]])
What does this code output?
medium
A. Top 3 documents ranked by combined similarity and MMR scores
B. Top 3 documents ranked by similarity score only
C. Top 3 documents ranked by MMR score only
D. Random 3 documents from the list

Solution

  1. Step 1: Analyze score calculation

    The code calculates a combined score using 60% similarity and 40% MMR for each document.
  2. Step 2: Understand sorting and output

    Documents are sorted by this combined score in descending order, then top 3 are printed.
  3. Final Answer:

    Top 3 documents ranked by combined similarity and MMR scores -> Option A
  4. Quick Check:

    Hybrid = combined scores [OK]
Hint: Check weighted sum and sorting for final ranking [OK]
Common Mistakes:
  • Ignoring MMR score in combined score
  • Assuming sorting by similarity only
  • Thinking output is random
4. Consider this buggy code snippet for MMR retrieval:
def mmr(query, docs, selected):
    scores = []
    for doc in docs:
        relevance = similarity(query, doc)
        diversity = min([similarity(doc, s) for s in selected])
        score = relevance - 0.5 * diversity
        scores.append((doc, score))
    return max(scores, key=lambda x: x[1])[0]
What is the main error causing a crash when selected is empty?
medium
A. Using min() on an empty list causes an error
B. Incorrect use of max() function
C. Missing return statement
D. Similarity function is undefined

Solution

  1. Step 1: Identify cause of crash

    When selected is empty, the list inside min() is empty, causing a ValueError.
  2. Step 2: Understand min() behavior

    min() cannot operate on empty lists, so the code crashes at that line.
  3. Final Answer:

    Using min() on an empty list causes an error -> Option A
  4. Quick Check:

    min(empty list) = error [OK]
Hint: Check min() on empty lists for errors [OK]
Common Mistakes:
  • Blaming max() instead of min()
  • Ignoring empty list edge case
  • Assuming similarity is undefined
5. You want to improve a search system by combining similarity and MMR retrieval. Which approach best balances relevance and diversity in the final results?
hard
A. Use MMR with a diversity weight of zero
B. Combine similarity and MMR scores with adjustable weights
C. Use only similarity scores to rank results
D. Randomly shuffle results after similarity ranking

Solution

  1. Step 1: Understand the goal

    Balancing relevance and diversity requires combining both similarity and MMR scores meaningfully.
  2. Step 2: Evaluate options

    Using only similarity or zero diversity weight ignores diversity; random shuffling loses relevance order.
  3. Step 3: Best approach

    Combining similarity and MMR with adjustable weights allows tuning the balance effectively.
  4. Final Answer:

    Combine similarity and MMR scores with adjustable weights -> Option B
  5. Quick Check:

    Hybrid weighted combination = best balance [OK]
Hint: Adjust weights to balance relevance and diversity [OK]
Common Mistakes:
  • Ignoring diversity by using similarity only
  • Setting diversity weight to zero in MMR
  • Randomizing results without scoring