Expectation

[Doom]

Hi, I'm learning about the expectation of probability, my teacher just told us the basic definition, it's in high school level which just said the expected value is a weighted mean. Then he gave us these examples but he doesn't explain anything about how to get the answers. It's tough for me to figure it out now. I want to know the steps to do it, and some suggestions how to fully understand it.

 

[mmm4444bot]

my teacher … just said the expected value is a weighted mean. Then he gave us these examples but he doesn't explain anything about how to get the answers.

Hello. Does your teacher expect you to solve those problems, or are you simply asking for help out of curiosity?

?

 

[Doom]

Hello. Does your teacher expect you to solve those problems, or are you simply asking for help out of curiosity?

?

I think he may expect us to solve that. Most of us in the class have somewhat strong mathematical background from what he said, unfortunately I don't. XD

 

[blamocur]

I think he may expect us to solve that. Most of us in the class have somewhat strong mathematical background from what he said, unfortunately I don't. XD

1. Are you familiar with the definition of expected values of random variables with know probability distribution function (PDF)?
2. Do you know how do compute expected value of a function of a random variable?
3. How about random vectors? If you X and Y are independent with known PDFs do you know how to compute PDF for the vector (X,Y)?

 

[JeffM]

Have you studied integral calculus? If not, I greatly doubt you have the tools to handle this course.

 

[Doom]

1. Are you familiar with the definition of expected values of random variables with know probability distribution function (PDF)?
2. Do you know how do compute expected value of a function of a random variable?
3. How about random vectors? If you X and Y are independent with known PDFs do you know how to compute PDF for the vector (X,Y)?

1. Yes, I know the definition of expected values and PDF, I'm gonna review it.
2. Yes, same as the 1st question
3. No, I can't handle many problems related to vectors yet.

 

[Doom]

Have you studied integral calculus? If not, I greatly doubt you have the tools to handle this course.

I have studied integral calculus in my 1st year undergraduate course but it has been a long time ago. I need some time to review it.

 

[blamocur]

3. No, I can't handle many problems related to vectors yet.

Instead of "vectors" Wikipedia describes "Densities associated with multiple variables", but they are talking about the same things, i.e. vectors whose coordinates are random variables. I've also found this lecture notes, which talk of random vectors.

 

[Doom]

Instead of "vectors" Wikipedia describes "Densities associated with multiple variables", but they are talking about the same things, i.e. vectors whose coordinates are random variables. I've also found this lecture notes, which talk of random vectors.

Thank you but I cannot open the lecture notes link

 

[blamocur]

Instead of "vectors" Wikipedia describes "Densities associated with multiple variables", but they are talking about the same things, i.e. vectors whose coordinates are random variables. I've also found this lecture notes, which talk of random vectors.

Sorry, I must have mistyped it somehow: https://www.cs.toronto.edu/~mbrubake/teaching/C11/Handouts/PDFs.pdf

 

[Doom]

Sorry, I must have mistyped it somehow: https://www.cs.toronto.edu/~mbrubake/teaching/C11/Handouts/PDFs.pdf

No problem, I will review it.