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Machine Learning Foundations 06 Apr 26 - 12 Apr 2026

MLF Quiz 213 questions40 marks5 MCQ · 5 SA · 3 MSQFoundation
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Q1MCQ4 marks
Consider a vector such that . Let , where is the identity matrix. Which of the following is true?
  1. is Hermitian and unitary.
  2. is Hermitian but not unitary.
  3. is unitary but not Hermitian.
  4. is neither Hermitian nor unitary.
Q2MCQ2 marks
If is a matrix with eigenvalues and , what is det ? Note: det denotes the determinant.
Q3MCQ3 marks
Let question figure be a Hermitian matrix. Which of the following options is correct for the values of and ?
Q4MCQ3 marks
Let question figure . Find the condition on and for which the matrix is positive-definite.
  1. and
  2. and
  3. and
Q5MCQ3 marks
Which of the following represents the Taylor series expansion up to the third degree term of question figure around ?
Q6MSQ3 marksselect all that apply
If is a real matrix of shape , which of the following is/are true?
  1. is a positive semi-definite matrix.
  2. is a positive semi-definite matrix.
  3. is positive semi-definite if and only if is a symmetric matrix.
  4. is positive semi-definite if and only if is a square matrix.
Q7MSQ3 marksselect all that apply
Consider the following matrix for : question figure Which of the following options is/are correct?
  1. is unitary for all real values of other than .
  2. is unitary for .
  3. is unitary for .
  4. If , then all eigenvalues of satisfy .
  5. If is any non-zero real value, then all eigenvalues of satisfy .
Q8MSQ4 marksselect all that apply
Consider a function whose graph is shown below. and correspond to local minima of . question figure We run two separate instances of gradient descent with the same learning but different initial points. (1) Starting from the point (2) Starting from the point Assume that and are very small positive quantities. Which of the following is/are true if we run gradient descent for a large number of iterations?
  1. Instance (1) will converge to the point
  2. Instance (2) will converge to the point
  3. Both instances (1) and (2) will converge to
  4. Both instances (1) and (2) will converge to
  5. Instance (1) will not converge to , but will diverge to negative infinity
  6. Instance (2) will not converge to , but will diverge to infinity
Q9SA3 marks
Inscript is a real matrix of shape with the following singular values: . Find the rank of .
Q10SA3 marks
Consider the matrix question figure . Find the sum of all the singular values of .
Q11SA4 marks
A function is minimized using the gradient descent algorithm. Let denote the value of at which is minimized.Starting from the initial point , one iteration of gradient descent is performed with a learning rate of . If denotes the point obtained after this iteration, find the value of . Enter the answer correct to one decimal place.
Comprehension passage - the questions below it refer to this
Consider the following dataset in Run PCA on this dataset. Based on the above data, answer the given subquestions.
Q12SA2 marks
If question figure is the covariance matrix of the dataset, find . Enter the nearest integer as your answer.
Q13SA3 marks
Let be the unit-norm eigenvector corresponding to the smallest eigenvalue of the covariance matrix. Find the variance of the dataset along the direction . Enter the nearest integer as your answer.

Answer key

  1. Q1 (MCQ, 4 marks): A
  2. Q2 (MCQ, 2 marks): A
  3. Q3 (MCQ, 3 marks): C
  4. Q4 (MCQ, 3 marks): B
  5. Q5 (MCQ, 3 marks): A
  6. Q6 (MSQ, 3 marks): A, B
  7. Q7 (MSQ, 3 marks): C, D
  8. Q8 (MSQ, 4 marks): A, B
  9. Q9 (SA, 3 marks): 3
  10. Q10 (SA, 3 marks): 2
  11. Q11 (SA, 4 marks): 0.7 to 0.9
  12. Q12 (SA, 2 marks): 8
  13. Q13 (SA, 3 marks): 1