INTRODUCTION TO MACHINE LEARNING Week 3
Session: JAN-APR 2023
Course Name: Introduction to Machine Learning
Course Link: Click Here
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q1. Which of the following is false about a logistic regression based classifier?
a. The logistic function is non-linear in the weights
b. The logistic function is linear in the weights
c. The decision boundary is non-linear in the weights
d. The decision boundary is linear in the weights
Answer: b, c
Q2. Consider the case where two classes follow Gaussian distribution which are cen- tered at (3, 9) and (−3, 3) and have identity covariance matrix. Which of the following is the separating decision boundary using LDA assuming the priors to be equal?
a. y−x=3
b. x+y=3
c. x+y=6
d. both (b) and (c)
e. None of the above
f. Can not be found from the given information
Answer: c. x+y=6
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q3. Consider the following relation between a dependent variable and an independent variable identified by doing simple linear regression. Which among the following relations between the two variables does the graph indicate?

a. as the independent variable increases, so does the dependent variable
b. as the independent variable increases, the dependent variable decreases
c. if an increase in the value of the dependent variable is observed, then the independent variable will show a corresponding increase
d. if an increase in the value of the dependent variable is observed, then the independent variable will show a corresponding decrease
e. the dependent variable in this graph does not actually depend on the independent variable
f. none of the above
Answer: e. the dependent variable in this graph does not actually depend on the independent variable
Q4. Given the following distribution of data points:

What method would you choose to perform Dimensionality Reduction?
a. Linear Discriminant Analysis
b. Principal Component Analysis
Answer: a. Linear Discriminant Analysis
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q5. In general, which of the following classification methods is the most resistant to gross outliers?
a. Quadratic Discriminant Analysis (QDA)
b. Linear Regression
c. Logistic regression
d. Linear Discriminant Analysis (LDA)
Answer: c. Logistic regression
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q6. Suppose that we have two variables, X and Y (the dependent variable). We wish to find the relation between them. An expert tells us that relation between the two has the form Y=m+X2+c. Available to us are samples of the variables X and Y. Is it possible to apply linear regression to this data to estimate the values of m and c?
a. no
b. yes
c. insufficient information
Answer: a. no
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q7. In a binary classification scenario where x is the independent variable and y is the dependent variable, logistic regression assumes that the conditional distribution y|x follows a
a. Bernoulli distribution
b. binomial distribution
c. normal distribution
d. exponential distribution
Answer: a. Bernoulli distribution
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q8. Consider the following data:

Assuming that you apply LDA to this data, what is the estimated covariance matrix?
a. [1.8750.31250.31250.9375]
b. [2.50.41670.41671.25]
c. [1.8750.31250.31251.2188]
d. [2.50.41670.41671.625]
e. [3.251.16671.16672.375]
f. [2.43750.8750.8751.7812]
g. None of these
Answer: e. [3.251.16671.16672.375]
Q9. Given the following 3D input data, identify the principal component.

(Steps: center the data, calculate the sample covariance matrix, calculate the eigenvectors and eigenvalues, identify the principal component)
a. [−0.1022 0.0018 0.9948]
b. [0.5742 −0.8164 0.0605]
c. [0.5742 0.8164 0.0605]
d. [−0.5742 0.8164 0.0605]
e. [0.8123 0.5774 0.0824]
f. None of the above
Answer: e. [0.8123 0.5774 0.0824]
Q10. For the data given in the previous question, find the transformed input along the first two principal components.
a.

b.

c.

d.

e. None of the above
Answer: c
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
More Weeks of Introduction to Machine Learning: Click Here
More Nptel courses: https://progiez.com/nptel
Session: JUL-DEC 2022
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Course Name: INTRODUCTION TO MACHINE LEARNING
Link to Enroll: Click Here
Q1. For linear classification we use:
a. A linear function to separate the classes.
b. A linear function to model the data.
c. A linear loss.
d. Non-linear function to fit the data.
Answer: b. A linear function to model the data.
Q2. Logit transformation for Pr(X=1) for given data is S=[0,1,1,0,1,0,1]
a. 3/4
b. 4/3
c. 4/7
d. 3/7
Answer: c. 4/7
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q3. The output of binary class logistic regression lies in this range.
a. [−∞,∞]
b. [−1,1]
c. [0,1]
d. [−∞,0]
Answer: d. [−∞,0]
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q4. If log(1−p(x)1+p(x))=β0+βxlog What is p(x)p(x)?
Answer: d.
Q5. Logistic regression is robust to outliers. Why?
a. The squashing of output values between [0, 1] dampens the affect of outliers.
b. Linear models are robust to outliers.
c. The parameters in logistic regression tend to take small values due to the nature of the problem setting and hence outliers get translated to the same range as other samples.
d. The given statement is false.
Answer: d. The given statement is false.
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q6. Aim of LDA is (multiple options may apply)
a. Minimize intra-class variability.
b. Maximize intra-class variability.
c. Minimize the distance between the mean of classes
d. Maximize the distance between the mean of classes
Answer: b. Maximize intra-class variability.
Q7. We have two classes in our dataset with mean 0 and 1, and variance 2 and 3.
a. LDA may be able to classify them perfectly.
b. LDA will definitely be able to classify them perfectly.
c. LDA will definitely NOT be able to classify them perfectly.
d. None of the above.
Answer: a. LDA may be able to classify them perfectly.
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q8. We have two classes in our dataset with mean 0 and 5, and variance 1 and 2.
a. LDA may be able to classify them perfectly.
b. LDA will definitely be able to classify them perfectly.
c. LDA will definitely NOT be able to classify them perfectly.
d. None of the above.
Answer: b. LDA will definitely be able to classify them perfectly.
Q9. For the two classes ’+’ and ’-’ shown below.
While performing LDA on it, which line is the most appropriate for projecting data points?
a. Red
b. Orange
c. Blue
d. Green
Answer: b. Orange
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
Q10. LDA assumes that the class data is distributed as:
a. Poisson
b. Uniform
c. Gaussian
d. LDA makes no such assumption.
Answer: d. LDA makes no such assumption.
These are Introduction to Machine Learning Week 3 Assignment 3 Answers
More NPTEL Solutions: https://progies.in/answers/nptel
* The material and content uploaded on this website are for general information and reference purposes only. Please do it by your own first. COPYING MATERIALS IS STRICTLY PROHIBITED.
More from PROGIEZ
