The distribution of function of random variable

Click For Summary

Discussion Overview

The discussion revolves around the distribution of a function of a random variable, specifically in the context of a Bernoulli trial involving a fair coin. Participants are examining how to derive the distribution of a transformed variable based on given data and comparing their findings with a solution provided in a textbook.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Homework-related

Main Points Raised

  • One participant describes their approach to finding the distribution of a variable y derived from a random variable x, mentioning a plot and intervals in the cumulative distribution function Fx(x).
  • Another participant points out the lack of necessary information in the initial post, suggesting that the solution from the book and the distribution definition are missing.
  • A participant provides the density function for x as a Bernoulli trial, indicating that the distribution resembles a staircase pattern.
  • It is noted that the probabilities p and q for the coin are both 0.5, as it is a fair coin.
  • One participant questions whether the goal is to determine if the coin is fair based on the number of heads and tails observed in the tosses.

Areas of Agreement / Disagreement

There is no clear consensus among participants regarding the correctness of the initial approach or the textbook solution. Multiple competing views and uncertainties remain about the distribution and the necessary information for resolution.

Contextual Notes

Participants have not provided the textbook solution or the definition of the distribution, which may limit the clarity of the discussion. The assumptions regarding the fairness of the coin and the specific intervals used in the cumulative distribution function are also not fully detailed.

ecesiu
Messages
7
Reaction score
0
i have this question
image.png

i do find the distribution like this figure :
dis.png

and i plot the y like this:
g_x.png

now i want to find the distribution of y
i tried to take the distribution for each interval in Fx(x) like this :
image.png

but the solution in the book said :
image.png

who is wrong me or the book please help
 
Physics news on Phys.org
Hey ecesiu and welcome to the forums.

You missed out giving us any of the information.
 
which information you mean?
 
Like the solution the book gave, the distribution definition, all the other relevant information: stuff like that.
 
firest i found the density of x which is Bernoulli trial :
PK=Cn(10,k) * p^k * q^(10-k) , k= 0,1,...,10
the distribution is a staircase of the density
which i sketch , the book solution is here :
image.png
 
p=q=0.5 because the coin is fair
where p is the probability of getting head , q is the probability of getting tail
 
So what are you trying to do? Are you trying to figure out whether you think a coin is fair given a number of tosses for heads and tails?
 

Similar threads

  • · Replies 30 ·
2
Replies
30
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K