Having a little trouble with functions of random variables

In summary, the problem involves finding the PDF of Y when X follows a uniform distribution. The solution involves finding the CDF of Y and then taking the derivative to get the PDF. The final answer is -ln(1-y).
  • #1
bennyska
112
0

Homework Statement


Let X ~UNIF(0,1), and Y=1-e-x. Find the PDF of Y


Homework Equations





The Attempt at a Solution


So i have Fy=Pr(Y<y)
=Pr(1-e-x<y)
=Pr(-e-x<y-1)
=Pr(e-x>1-y)
=Pr(-x>ln(1-y)
=pr(x<-ln(1-y)
=Fx(-ln(1-y))
(here is where I'm having a breakdown)
=x|0 to -ln(1-y) which doesn't really make sense... (that's my notation for evaluate from 0 to...)
i'm having a similar problem, and i think if i can get this figured out, i'll be able to do that one as well.
 
Physics news on Phys.org
  • #2
OK, so you got

[tex]F(y) = \int_0^{-\log (1-y)} dx = -\log (1-y)[/tex]

Why do you think it doesn't make sense?
 
  • #3
i was making a few dumb mistakes. got it taken care of. thanks.
 

1. What are random variables and why are they important in scientific research?

Random variables are quantities that can take on different values in a given experiment or event. They are important in scientific research because they help us understand the probabilistic nature of the world and make predictions about the outcomes of experiments.

2. What is the difference between a discrete and continuous random variable?

A discrete random variable can only take on a finite or countably infinite number of values, while a continuous random variable can take on any value within a certain range. Discrete random variables are often associated with counting, while continuous random variables are associated with measurements.

3. How do you calculate the expected value of a random variable?

The expected value of a random variable is calculated by multiplying each possible value of the variable by its corresponding probability, and then summing all of these values. This gives an estimate of the average value of the random variable over many trials.

4. What is a probability distribution and how is it related to random variables?

A probability distribution is a function that assigns probabilities to the different values that a random variable can take on. It shows the likelihood of each possible outcome, and is closely related to random variables because it describes the behavior of these variables in a given experiment or event.

5. How can functions of random variables be used in real-world applications?

Functions of random variables can be used to model and analyze a wide range of real-world phenomena, such as stock prices, weather patterns, and human behavior. They can also be used to make predictions and inform decision making in fields such as finance, economics, and engineering.

Similar threads

  • Calculus and Beyond Homework Help
Replies
1
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
752
  • Calculus and Beyond Homework Help
Replies
10
Views
820
  • Calculus and Beyond Homework Help
Replies
2
Views
252
  • Calculus and Beyond Homework Help
Replies
8
Views
1K
  • Calculus and Beyond Homework Help
Replies
4
Views
2K
  • Calculus and Beyond Homework Help
Replies
1
Views
692
  • Calculus and Beyond Homework Help
Replies
3
Views
310
  • Calculus and Beyond Homework Help
Replies
7
Views
1K
  • Set Theory, Logic, Probability, Statistics
Replies
7
Views
426
Back
Top