Probablity question (confused on the pdf)

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Homework Help Overview

The discussion revolves around a probability density function (pdf) defined piecewise, where participants are examining its properties, particularly concerning its boundedness and integration to 1.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the conditions under which a function qualifies as a pdf, questioning the requirement for it to be bounded by 1 and discussing the implications of integrating the function.

Discussion Status

Some participants have provided clarifications regarding the properties of pdfs, while others are still grappling with the implications of the function's behavior across its defined intervals. There is an acknowledgment of the need to demonstrate that the function integrates to 1.

Contextual Notes

There is a mention of confusion regarding the definition of a pdf and its properties, particularly in relation to the specific function presented and its behavior outside the interval [0, 1].

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Homework Statement

<br /> $f(x)=\begin{cases}<br /> 7(4)^{-i} &amp; x\in(\frac{1}{2^{i}},\frac{1}{2^{i-1}}],i=1,2,3,...\\<br /> 0 &amp; 0\geq x,x&gt;1<br /> \end{cases}$ (please excuse the poor latex)<br /> <h2>Homework Equations</h2><br /> <br /> <br /> <br /> <h2>The Attempt at a Solution</h2><br /> the problem I&#039;m having is say x=3/4. then according to the pdf, shouldn&#039;t P(x)=7*(4^-1)=7/4&gt;1. i mean, shouldn&#039;t it be bounded by 1? when i integrate this out, i get 1, like i should, so I&#039;m not sure what mistake I&#039;m making.
 
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what is the actual question? Maybe I'm missing it, but it seems like you just posted an equation without any description of what you are trying to do
 
Why do you expect that a pdf must be bounded by 1? Consider a random variable that is uniformly distributed over the interval [0, 1/2]. Is that pdf bounded by 1?
 
well, the actual problem is show that this function is a pdf. so i need to show that it integrates to 1, which it does, but i believe i also need to show that it's bounded by 0 and 1 for all x in the domain, which is the problem I'm having a hard time with.
 
oh, got it. duh. thank you.
 

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