Practice Marginal Pmf (discrete) (14.3.1) - Joint Probability Distributions

Practice: Marginal PMF (Discrete)

Lesson 14.3.1Joint Probability Distributions

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9 questions

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6 sample questions

Question 1.
What is the formula for calculating the marginal PMF of variable X?
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Think about how you want to isolate the variable X.
Question 2.
Provide an example of a discrete random variable.
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Consider discrete outcomes from an experiment.
3Question 3.
What is the marginal PMF of variable X?
- Calculated by summing probabilities of the joint distribution for Y
- Independently calculated from the other variables
- Equal to the joint PMF of X
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Remember the formula for marginal PMF!
4Question 4.
Marginal PMFs help in understanding the relationship between variables. True or False?
- True
- False
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Reflect on the importance of isolating each variable.
Question 5.
A joint PMF is defined as follows: $P(X=0, Y=0) = 0.1, P(X=0, Y=1) = 0.2, P(X=1, Y=0) = 0.3, P(X=1, Y=1) = 0.4$ . If you add a new variable Z such that Z can take values 1 or 0, how does that affect the calculation of marginal PMFs for X?
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Focus on how new variables interact with existing distributions.
Question 6.
If two discrete random variables X and Y have identical marginal distributions but are dependent, provide a scenario in which this can occur.
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Think about variables where one's outcome affects the other.

5 more questions in this section. Enroll free to practise them all.