The IIT Madras BS Machine Learning Techniques (MLT) Quiz 2 paper sat on 12 Apr 2026, in the January 2026 term, set 1-3: 15 questions for 40 marks in 120 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
PCA has reduced the dimensionality of the dataset because the combinations of features are de-correlated.
PCA has not reduced the dimensionality of the dataset because all principal components are retained.
PCA always reduces the dimensionality of the dataset regardless of the number of components retained.
PCA can never be used for dimensionality reduction.
Correct answer
PCA has not reduced the dimensionality of the dataset because all principal components are retained.
Correct answer
40
60
100
1
Correct answer
100
Which among the following is TRUE for k-NN algorithm? Select all that apply.
1-nearest neighbour is sensitive to outliers.
k-NN can only be applied to a classification problem.
As k increases, the model is more likely to overfit.
The bias increases with the increase in the value of k.
The variance increases with the increase in the value of k.
Correct answers
1-nearest neighbour is sensitive to outliers.
The bias increases with the increase in the value of k.
30
120
50
160
Correct answers
30
120
50
Correct answers
With respect to the Lloyd’s algorithm, choose the correct statements:
The partition configurations cannot repeat themselves.
After doing the reassignments (consider at least one point reassigned to the new cluster), we might get the same means for all clusters.
Objective function after making the re-assignments strictly reduces.
Objective function after making the re-assignments strictly increases.
Correct answers
The partition configurations cannot repeat themselves.
Objective function after making the re-assignments strictly reduces.
Correct answer: 0.12 (accepted within ±0.02)
Correct answer: 0.5
Correct answer: 0.693 (accepted within ±0.003)
Based on the above data, answer the given subquestions.
The coefficients shrinks towards zero.
The coefficients increases in magnitude.
The coefficients remain unchanged.
Correct answer
The coefficients shrinks towards zero.
Based on the above data, answer the given subquestions.
What is the probability that a 60-year-old patient with a cholesterol level of 200 mg/dL has the disease? Enter the answer correct to two decimal places.
Correct answer: 0.73 (accepted within ±0.02)
Based on the above data, answer the given subquestions.
How high should the cholesterol level be for the patient mentioned in the previous question to have a 50% chance of being diagnosed with the disease?
Correct answer: 150
Consider the datapoints (−2,−2) with label +1 and (2, 2) with label −1. A hard margin SVM is applied on this dataset. Answer the given subquestions:
Which of the following is the decision boundary for the given dataset?
Correct answer
Consider the datapoints (−2,−2) with label +1 and (2, 2) with label −1. A hard margin SVM is applied on this dataset. Answer the given subquestions:
Correct answer: 5.66 (accepted within ±0.02)
