Quiz Space

Stats 2 week 2 important questions

Week 2 of Statistics for Data Science II: Independence, functions of RVs. Extra important questions based on the recent, changing patterns of the exams, from basic to advanced. Practise them in learning mode: each question has a worked solution.

Question 1

One correct option

The joint pmf of XX and YY is

XbackslashY1200.30.210.30.2\begin{array}{c|cc} X\\backslash Y & 1 & 2 \\ \hline 0 & 0.3 & 0.2 \\ 1 & 0.3 & 0.2 \end{array}

Are XX and YY independent?

  1. A

    They are independent only if the table is symmetric

  2. B

    Yes, XX and YY are independent

  3. C

    No, XX and YY are not independent

  4. D

    Independence cannot be decided from a joint pmf

Question 2

One correct option

The joint pmf of XX and YY is

XbackslashY12300.050.050.310.050.30.25\begin{array}{c|ccc} X\\backslash Y & 1 & 2 & 3 \\ \hline 0 & 0.05 & 0.05 & 0.3 \\ 1 & 0.05 & 0.3 & 0.25 \end{array}

Are XX and YY independent?

  1. A

    Independence cannot be decided from a joint pmf

  2. B

    They are independent only if the table is symmetric

  3. C

    No, XX and YY are not independent

  4. D

    Yes, XX and YY are independent

Question 3

One correct option

The joint pmf of XX and YY is

XbackslashY12300.10.040.0610.30.120.1820.10.040.06\begin{array}{c|ccc} X\\backslash Y & 1 & 2 & 3 \\ \hline 0 & 0.1 & 0.04 & 0.06 \\ 1 & 0.3 & 0.12 & 0.18 \\ 2 & 0.1 & 0.04 & 0.06 \end{array}

Are XX and YY independent?

  1. A

    Independence cannot be decided from a joint pmf

  2. B

    Yes, XX and YY are independent

  3. C

    No, XX and YY are not independent

  4. D

    They are independent only if the table is symmetric

More questions in this week

Authorise with Google to see every question with its answer and explanation and practise it in learning mode.