Question 1
Answer the subquestions.
Suppose X is a continuous random variable uniformly distributed between −1 and 1. Let Y be another random variable such that Y = X². Calculate Cov[X, Y ].
The IIT Madras BS Statistics for Data Science II (Stats 2) Quiz 1 paper sat on 30 Jan 2022, in the January 2022 term, set QPB1: 23 questions for 50 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.
Answer the subquestions.
Suppose X is a continuous random variable uniformly distributed between −1 and 1. Let Y be another random variable such that Y = X². Calculate Cov[X, Y ].
Correct answer: 0
Answer the subquestions.
Select three facts/formulae/steps from the list of options that you will use for solving previous question.
Note: "This question is optional. We will check your answer to this question if you make a mistake in the previous one. Please enter your answers in comma-separated format. E.g. 1,2,3". Check the list of options given in the data attachment.
Correct answer: 3, 5, 8, 16
Use the following information to answer the subquestions
Which of the following options are true?
Correct answers
Use the following information to answer the subquestions
Find the value of P(X1 = 0 | Y = 8). Enter the answer correct to one decimal place.
Correct answer: 0.2
Use the following information to answer the subquestions
Select three facts/formulae/steps from the list of options that you will use for solving previous questions no 5 & 6.
Note: "This question is optional. We will check your answer to this question if you make a mistake in the previous one. Please enter your answers in comma-separated format. E.g. 1,2,3". Check the list of options given in the data attachment.
Correct answer: 2, 4, 9, 12, 17, 22
Use the following information to answer the subquestions
Find the joint PMF of X1 and X2.
Correct answer
Use the following information to answer the subquestions
Find the probability that Kasparov loses the second game. Enter the answer correct to two decimal places.
Correct answer: 0.68
Use the following information to answer the subquestions
Which of the following is true about Y ?
Y is a monotonically increasing function of X.
Y is a monotonically decreasing function of X.
Correct answer
Y is a monotonically increasing function of X.
Use the following information to answer the subquestions
Find the support of Y .
Correct answer
Use the following information to answer the subquestions
Find the distribution of Y .
Correct answer
Use the following information to answer the subquestions
Choose the correct options from the following:
Correct answers
Use the following information to answer the subquestions
Find the marginal distributions of X and Y .
Correct answer
Use the following information to answer the subquestions
Find P(X = 3, Y = 3). (Enter the answer correct to three decimal places)
Correct answer: 0.027 (accepted within ±0.004)
Answer the subquestions.
The time of an interview follows an exponential distribution with an average time of 20 minutes. Find the probability that the interview lasted more than 15 minutes given that it was between 12 and 18 minutes. (Enter the answer correct to two decimal places)
Correct answer: 0.46 (accepted within ±0.01)
Answer the subquestions.
Select three facts/formulae/steps from the list of options that you will use for solving previous question.
Note: "This question is optional. We will check your answer to this question if you make a mistake in the previous one. Please enter your answers in comma-separated format. E.g. 1,2,3". Check the list of options given in the data attachment.
Correct answer: 4, 11, 15, 20, 21
Answer the subquestions.
Correct answer: 0.25
Answer the subquestions.
Select three facts/formulae/steps from the list of options that you will use for solving previous question.
Note: "This question is optional. We will check your answer to this question if you make a mistake in the previous one. Please enter your answers in comma-separated format. E.g. 1,2,3". Check the list of options given in the data attachment.
Correct answer: 6, 7, 10, 12, 14, 18
Answer the subquestions.
Correct answer: 0.72
Answer the subquestions.
Select three facts/formulae/steps from the list of options that you will use for solving previous question.
Note: "This question is optional. We will check your answer to this question if you make a mistake in the previous one. Please enter your answers in comma-separated format. E.g. 1,2,3". Check the list of options given in the data attachment.
Correct answer: 1, 13, 19, 23
The marks of students in a class is normally distributed with mean μ and standard deviation 10. If 10% of the students have scored more than 80, find the value of μ.
Correct answer
Correct answer
Two unbiased dice are thrown repeatedly. Find the expected number of trials needed to get the same value on both the dice.
Correct answer: 6
Correct answers