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11. Partial Differential Equations
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12 questions on this section. Wrong answers show you what to read again.
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Revision test
Mixed questions from across the chapter. Your answers get marked.
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Flashcard drill
5 cards from this lesson. Good the night before a test.
Try these first
- 1.
Define raw moment and give an example.
Hint
Think about the expected values.
- 2.
What does variance measure?
Hint
Consider how values deviate from the average.
- 3.
What is the first moment known as?
- Skewness
- Variance
- Mean
Hint
Think about what the average value represents.
- 4.
True or False: The second central moment is equal to the variance.
- True
- False
Hint
Remember how variance is defined.
- 5.
Given a random variable X with MGF M_X(t) = e^{(μ + σ^2 t^2)/2}, find the first and second moments.
Hint
Remember that the first moment is the first derivative evaluated at t=0.
- 6.
Calculate the variance from a given MGF, M_X(t) if its derivatives provide moments: M'_X(0) = 2, M''_X(0) = 6.
Hint
Use the relationship between variance and moments.
Exercises
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting
4 more questions available
Enrol freeQuiz
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting
2 more questions available
Enrol freeChallenge Problems
Total Questions
2
Estimated Time
4 min
Passing Score
70%
Instructions
- Read each question carefully
- You can use hints if you need help
- Complete all questions before submitting