Pdf Definition and 328 Threads

What is the PDF of the exponential of a Gaussian random variable? i.e. suppose W is a random variable drawn from a Gaussian distribution, then what is the random distribution of exp(W)? Thank you!

Does anyone know of any software that can convert a PDF with complex equations to Word? Word uses cambriamath and products like adobe are not equipped to convert from PDF to Word. The issue is this - we need to update many equations and charts which are currently in a PDF format. We need...

Homework Statement Given: The joint probability distribution function of X and Y: f(x,y) = 2xe^(-y), x > 0, y > x^2 0, otherwise Obtain the pdf of V = (X^2)/Y The Attempt at a Solution The interval of V is (0,1) because Y is always...

The question is "An experiment in which a dice is tossed twice. Let X be the random variable defined by recording the higher of the 2 values obtained in the experiment. Determine the probability distribution of X." I know that the range of this distribution is {1,2,3,4,5,6}. For P(X=1) both...

Homework Statement If X is a Poisson random variable with \lambda = 2 find the probability that X>0.5. Homework Equations The Poisson PDF: P(x,\lambda) = \frac{\lambda^k}{k!}e^{-\lambda} The Attempt at a Solution Usually with these sorts of probability problems where they ask...

Hey guys, So I'm having trouble telling what the integration bounds should be when calculation the marginal PDF of two random variables. So the joint PDF fX1,X2(x1,x2) is a constant C = 1 in the regions x1 and x2. The regions are bound by 0<=x1<=1 and 0<=x2<=2(1-x1). If the marginal PDFs are...

Oops, I accidentally edited over this post =( Thankfully it's quoted in the next one.

Hi all 1) When we are performing detection , and we have received this y(n)=x(n)+z(n) for n=0,1,2,3..., where z is gaussian noise, but about x(n) we don't know its distribution , all we know that it is I.I.D. random variable with zero mean and fxed given variance. Now my question is can we...

Homework Statement random variable of X has pdf: f(x) = (3/16)*x2 from interval (-2,2). Also, E(X) = 0, and E(X2) = 12/5. Find the pdf of Y = X2 Homework Equations The Attempt at a Solution I don't really know where to start.

Hi, Suppose we have two random variables X and Y with CDFs and PDFs F_X(x), F_Y(y), f_X(x), and f_Y(y). Now suppose that a new random variable formed as Z=(X+Y)^2. How can we find the CDF F_Z(z) and the PDF f_Z(z) of this new random variable? Note: X and Y are independent random variables. Thanks

hey everyone, i have an ebook in pdf form and wanted some help with some of the portions there. online hosting services like flickr and imageshack don't allow uploading of pdf pages. while reading the book i can annotate, highlight etc. the only option I'm left with is to convert pdf pages to...

Hi guys, I have a problem with exporting to PDF format from Mathematica 7.0. As seen in the attachment PlotLabel is correctly displayed in the note book (test.nb), but when I try to export it, some characters just don't seem to be displayed correctly (plot.pdf). I've tried the "Save...

Suppose φ(x) and Φ(x) denote the familiar standard normal pdf and cdf. I am interested in an expression for the integral: S φ(ax+b) Φ(x) dx, from ZERO to INFINITY. Many thanks

Hey all, I have an engineering background with a pretty terrible grounding in statistics and just about all maths that I can't immediately visualize as some kind of dynamic system, so forgive me if this is an obvious question! I am working through a set of derivations for a conditional...

Any help is appreciated on this: This is the projection on the x-axis of a 2-bar linkage. I need to find the PDF of the end of the second link (point B) 1. Link C of length rC is pinned at the origin and its other end is pinned to link B at point C. Its length projected on the x-axis is...

Question: The r.v. X has pdf f(x) = ax + bx^2 0<x<1 0 otherwise If E(x) = 0.6 , find i) P(X<0.5) ii) V(x) Solution: E(x) =0.6 = \mu Stuck here

Hi everybody while trying to find the pdf of user in CDMA, I got stuck up with an integral, which is given below: \int_0^1\frac{1}{x (\ln x)^{\frac{n-1}{n}}\sqrt{y^2-x^2}}dx where y is a constant and n is an integer. Please help me to solve this integral.

Hi, everybody. My problem is about Probability and Random Process. i can't understand the probability density function of sum of two random variables and function of product of two random variables. Here is my question with a part of a solution: how can i find these problems solutions and...

Homework Statement 1. Let X , Y and Z be independent random variables, uniformly distributed on the interval from 0 to 1. Use Theorem 3.8.1 twice to find the pdf of W = X + Y + Z . Thm. 3.8.1 States: If X & Y are continuous random varibles wth pdfs fx(x) and fy(y), respectively then...

I am stumped. I have that W=X+Y+Z and that S=X+Y These are all X, Y, & Z and Independent and Uniformly Distributed on (0,1) I found the pdf of S to be (Assume all these < rep. less than or equal to): S when 0<S<1 2-S when 0<S<1 So I continued: To do pdf of S+Z=W I figured...

Homework Statement X1, X2, X3 are three random variable with uniform distribution at [0 1]. Solve the PDF of Z=X1+X2+X3. Homework Equations The Attempt at a Solution PDF of Z, f_z=\int\intf_x1(z-x2-x3)*f_x2*f_x3 dx2 dx3 I saw the answer at http://eom.springer.de/U/u095240.htm, but I cannot...

Hi All, I'm wondering if ln(x) has any know distribution when x is a normal random variable? Also, is there any distribution for x that generate a known distribution for ln(x)? Thanks,

Hi, This is a homework problem that I'm having a very hard time with. We are given that f(x)=e^(-x) for X greater/equal to zero. The question is to find f(x|A) where A is the union of the events (1 less/equal x, and x greater than 10). I can't figure out how to go about doing this...I...

Let the joint PDF of (X,Y) be of the form: f(x,y) = 1/8x(x-y), 0<=x<=2, |y|<=x f(x,y) = 0 elsewhere Find P(X+Y<=2). The answer that my teacher gave was P(X+Y<=2)=∫01dx ∫-xx 1/8x(x-y)dy + ∫12dx ∫-x2-x 1/8x(x-y)dy I do not understand how my teacher could separate the integral like...

please excuse any inaccuracies in the following formulation of my problem. here it goes: 1. there are n discrete time steps 2. between every time step, transitions 0 -> 1, 1-> 0 can happen between states denoted by 0 and 1. the two possible transition directions are poisson processes, i.e...

When the weibull shape parameter beta is <1, the pdf is divergent at t=0 due to negative exponent of beta -1. With such a divergent distribution is it meaningful to use Weibull for beta <1?

hi, there is a figure that i want to include in my latex document. The figure is in someones thesis and i want to have just that one figure in my latex document but I am not sure how to this. in power point i can just use the snap shop feature but how do i do it for latex where it requires a...

Hi Everyone, Iam new one to join the MATLAB .My task is to plot PDF for the given data from the .dat file I have three columns which contains as below like .The first column says port no , second and third is the inter packet arrival times of packet 1 and packet 2 . The whole data is huge...

Dear all, How can I find the the following conditional probability: f_Y(y/\gamma_f\leq \gamma_0), where Y=\gamma_f+\text{min}(\gamma_h,\gamma_g), where all gammas with subscripts f, g, h are i.i.d exponential random variables. Thanks in advance

Hello Buddies, I need to calculate "covariance matrix" of the given joint PDF function. Joint PDF is fx(x1,x2,x3)=2/3(x1+x2+x3) over S (x1,x2,x3), 0<xi<1, i=1,2,3 How can I calculte the Covariance Matrix? Thanks

Homework Statement Suppose that the radius X of a circle is a random variable having the following p.d.f.: f(x)={ (1/8)(3x=1) for 0<x<2 0 otherwise Determine the p.d.f. of the area of the circle and the circumference of the circle. Homework Equations...

Homework Statement Let X be a uniform random variable in the interval [0,1] i.e., X = U [(0,1)]. Then a new random variable Y is given by Y= g(X), where g(x)= -a. ln(x). Show that Y is exponentially distributed. What is the mean of Y? Homework Equations fX(x) = 1/ lambda . exp (-x/...

I have four questions that need to be answered. They are from my university course that I am taking in general astronomy 2. Could anybody tell me how I would obtain the detailed solutions to arrive at the answers? I have attached a pdf file of the questions and answers, please download it and...

Hi guys, On my homework, I'm simulating a normal distribution on Mathematica by adding up a bunch of RandomReal[] , that is, uniform(0,1) random variables, and using the central limit theorem. I would like to plot both the histogram and the actual Gaussian probability density function on the...

Hi I have a lot of work regarding documents management. I am looking for a word to PDF converter software compatible with Windows XP and Windows Vista as well which can even batch convert files. Please recommend some conversion tool. Any help is appreciated! Thanks!

Homework Statement The integral from 0 to infinity of xe^[-x(1+y)]dy Homework Equations The Attempt at a Solution I can't figure out why the answer would be zero to a pdf. Also, for the indefinite integral the calculator produces the answer xy*e^(-x-xy). I cant' figure out...

Homework Statement For a given cdf: Fy(y) = 0 for y less than 0 = y^2 for the range 0 to 1 = 1 for all values greater than or equal to 1 the problem asks to find P(1/2 < Y < 3/4) first using the cdf and then using the pdf...

Homework Statement I understand that PDF is a derivative of CDF and hence CDF is the integral of PDF. But I don't understand the difference between PDF and simply probability? What exactly is the differece? What extra things does PDF tell us which simple probability does not? Homework...

Hey all i struggling to understand, these concepts. would some explain to me the relationship and differences the distribution of a random variable and a probabiltiy distribution. wikipedia says this about probability distribution "The probability distribution describes the range of possible...

Hi everyone, I have a simple question (assuming since it was only worth 5% of total marks in the exam) about the PDF of a random variable. Given that PDF of random signal equals p(X) = \Lambda(X), where \Lambda is the triangle function, what would be the PDF of the random signal Y, Y = -3X...

Hi guys, I was reading about monte carlo analysis in the introduction from a textbook, and they gave an example of a voltage divider. They assumed resistor values had an equal probability of having values between the two tolerances. I know this is a simplistic assumption and I was wondering...

Determination of a Joint pdf Hi all! Someone can help me with this problem? The duration of a certain type of bulbs has a exponential distribution with known parameter \lambda . Consider a set of n bulbs. Which is the joint pdf of the durations t_{i} of the n bulbs?

Homework Statement problems 4 and 7 from this pdf http://www.daisleyphysics.com/y2p/worksheets/em4ws5.pdf Homework Equations The Attempt at a Solution A friend of mine is bad with computers and she asked me to help find the answers.

Homework Statement Let X1 X2 X3 be independent and identically distributed random variables with common pdf f(x) = e^-x 0<x<infinity, zero elsewhere. Evaluate P(X1 < X2|X1 < 2X2) and P(X1 < X2 < X3|X3 < 1). The Attempt at a Solution Would appreciate any hints as to where to start...

Homework Statement Let X1 X2 X3 and X4 be four independent random variables, each with pdf f(x) = 3(1-x)2, 0<x<1, zero elsewhere. If Y is the minimum of these four variables, find the cdf and pdf of Y. The Attempt at a Solution P(Y<or= y) = 1 - P(Y>y) = 1 - P(X1>y, X2>y, X3>y...

Homework Statement Normalise \Psi(x,t) = Ae^{-\lambda |x|}e^{-i \omega t} Homework Equations (i.e. it must satisfy \int_{-\infty}^{\infty} |\Psi (x,t)|^2 dx=1) The Attempt at a Solution This is my first attempt at normalisation and I don't know how valid my reasoning is, can...

I have just been learning probability density function (pdf) and there is something I need to ask. I understand the idea that for any value v, the pdf (f(v)) gives the probability that a value picked from a data set is less than v. It seems ok to find mean,variance, skewness etc. when f(v) is...

cdf to pdf and vise versa hi i'm looking for help when going from a cdf function: F(x) = { 1- e^-αx^β x ≥ 0, α>0, β>0 { 0 x < 0 to getting the corresponding pdf also i am looking to do the opposite(pdf to cdf) for: f(x) = { (1 + α)/2 for -1 ≤ x ≤ 1, -1 ≤ α ≤ 1 { 0 otherwise i'm...

hi i'm looking for help when going from a cdf function: F(x) = { 1- e^-αx^β x ≥ 0, α>0, β>0 { 0 x < 0 to getting the corresponding pdf also i am looking to do the opposite(pdf to cdf) for: f(x) = { (1 + α)/2 for -1 ≤ x ≤ 1, -1 ≤ α ≤ 1...

Homework Statement In a square town that is 1.5 miles by 1.5 miles, the places of residence are uniformly distributed (2000 per square mile) over the whole town. Compute the joint probability density function for the spatial distribution of places of residence (fX, Y). Homework Equations...