Probability Question about CDFs

  • Thread starter Thread starter doggie_Walkes
  • Start date Start date
  • Tags Tags
    Probability
Click For Summary

Homework Help Overview

The discussion revolves around a probability problem involving probability density functions (PDFs) and cumulative distribution functions (CDFs). The original poster presents a random variable Z with a specified PDF and seeks to determine the PDF of another random variable X defined in terms of Z.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the process of finding the CDF of X and how it relates to the PDF of Z. There are questions about the notation used for the bounds of Z and the implications of that notation on the problem. Some participants express uncertainty about the definitions and steps involved in the calculations.

Discussion Status

The conversation is ongoing, with participants exploring different interpretations of the problem and clarifying the notation. There is an attempt to guide the discussion towards using the known CDF/PDF of Z to find that of X, but no consensus has been reached on the specific steps to take.

Contextual Notes

There is a noted confusion regarding the notation for the bounds of Z, which has led to clarification requests. The original poster's request for help indicates a need for further exploration of the problem rather than a straightforward solution.

doggie_Walkes
Messages
20
Reaction score
0
Just wondering if someone could help me out on a problem. i mean PDFs, not CDFs in the title. Soz

Thanks in advance.

<_ means greater and equal to

Well, if we give Z to be a random varible with a pdf of:

pdf of Z = (5/2)*z^3 if -1<_ z _> 1
0 otherwise

Suppose that X = 2-Z^2

What is the pdf of X?
 
Physics news on Phys.org
what do you think? the idea is to have a go and get some help with your work...
 
well if i first find the CDF of FX(x) then um, try plugging it into find the probablility of y<_y?
 
The notation -1 \le z \ge 1 doesn't make any sense. do you mean -1 \le z \le 1?
 
yes i do mean <br /> -1 \le z \le 1 <br />

can u help me on the question?
 
doggie_Walkes said:
well if i first find the CDF of FX(x) then um, try plugging it into find the probablility of y<_y?

ok so what is y & what do you plan to "plug-in"?

Based on the question, I would use the known CDF/PDF of Z and try & use it to calculate that of X
 

Similar threads

Replies
9
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
Replies
11
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
2
Views
2K
Replies
6
Views
2K
  • · Replies 5 ·
Replies
5
Views
1K