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0
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0answers
21 views

Dice expirements and random variable? [migrated]

Suppose I define a random variable X such that it represents the sum on the dice thrown. Now there are two ways to do the experiment 1) I use 2 dice, note their individual Xi (R.V) and then find ...
0
votes
1answer
35 views

Import command gives different solution to equation than cut & paste

I would like to import values from a text file to run a notebook. The notebook works fine when I cut and paste in all the input values manually. Here is a working version. But when I import the same ...
4
votes
0answers
63 views

RandomVariate, MSE and Cramer-Rao bound calculation

I'm using the following code to plot the variance of a moment estimate of a parameter of Rice distribution and its' Cramer-Rao bound. First I generate $10^3$ vectors $\texttt{R}$ ($10^3$ elements ...
0
votes
1answer
29 views

Fit process parameters to a transformed AR(1) process

I would like to fit the parameters of an exponented AR(1) process using Mathematica's EstimatedProcess, however, the function does not seem to evaluate to anything. First of all I create the ...
0
votes
1answer
96 views

how to scale the plot of PDF (t-distribution)

The directions in my book say: "To sketch the t distribution in Figure 3.11, simply multiply the abscissa t value by the scale factor and plot this against the ordinate of t at that point." So ...
0
votes
1answer
62 views

Sketch Probability density function [closed]

My question is : Suppose that the PDF of a random variable X is as follows: \begin{equation*} f(x) = \begin{cases} ce^{-2x} & \text {$x > 0$}\\ 0 & \text {otherwise}\\ ...
1
vote
2answers
60 views

Maximum likelihood estimation based on frequency table

I have a frequency table of grades, I'm trying to estimate the distribution as a truncated normal distribution (a grade below 65 is a failing grade and doesn't count). Since I don't have the actual ...
0
votes
1answer
79 views

Periodic Gaussian Process's Covariance Matrix not Positive Definite

I'm trying to implement a periodic Gaussian Process: GP = Table[Exp[-.1 Sin[\[Pi] (x - y)]^2], {x, 0., 3, .1}, {y, 0., 3, .1}]; PositiveDefiniteMatrixQ[GP] ...
10
votes
1answer
171 views

Rapid density estimation and rendering of decision regions

I would like to create an interactive demonstration using Manipulate[] that illustrates a fundamental concept in pattern classification and machine learning. This ...
1
vote
3answers
176 views

Find 2 points in a normal distribution with these given properties

I would like to find a and b. How should I code this in Mathematica? What I did wrong? ...
1
vote
0answers
47 views

Help with Multivariate ProbabilityDistribution

I wish to obtain numbers from ...
1
vote
1answer
64 views

Find a probability with random variates from the same distribution

I'm trying to find Probability involving 3 random variates from the same distribution, but Mathematica does not seem to solve it. ...
0
votes
1answer
47 views

Central Limit Theorem - solve for a const, given probability

I hope this is not a very complicated question, but I have problems finding the answer. Quite often, I need to calculate something like this: $P(-a<\bar{x}<a) = p$, where $\bar{x}$ refers to the ...
2
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0answers
52 views

Parsing RLink RObject for aovlist and other object types

There are some slightly similar requests out there (e.g. Getting R textual output into Mathematica ) but I'm wondering if anyone has put together a more general purpose solution to parsing ...
2
votes
1answer
160 views

on Kolmogorov-Smirnov test

I found a problem to calculate Kolmogorov-Smirnov test statistic or p-value the data is ...
2
votes
0answers
103 views

Distance between vectors does not match distance between probability distribution [closed]

I have vectors that describe shapes. I am doing Euclidian distance between vectors to get the similar shapes and I get a good results of all classes. Theoretically, two similar shapes (shapes in a ...
4
votes
1answer
94 views

How to use Tandem Queueing Network Process?

Mathematica provides QueueingNetworkProcess and QueueingProcess. However, I can't seem to figure out how to create a tandem ...
0
votes
0answers
109 views

Latin Hypercube Sampling

I'm looking into Mathematica and I can't find if there is an instruction or a set of them that can perform the Latin Hypercube Sampling, given variable, their ...
3
votes
1answer
58 views

TransformedDistribution with respect to new variable

Given a custom pdf $f_x(x)$, I'm trying to find it's transformation $f_y(y)$ where $$y=x^2$$ and $$f_x(x)=30*x^2 (1 - x)^2, 0<x<1$$ I tried to using the following commands: ...
3
votes
1answer
104 views

How to use a custom CDF in a Kolmogorov-Smirnov test

How do I use a custom CDF that I defined for a Kolmogorov-Smirnov test. I have one input vector of data whose CDF I claim to have derived but want to check whether it agrees with my closed form ...
5
votes
1answer
88 views

How to use DegreeGraphDistribution with directed graphs?

DegreeGraphDistribution supports directed graphs because it has a DirectedEdges option. How can I specify the in-degree ...
0
votes
1answer
135 views

How to include constraints in `NMaximize`

I am trying to find maximum likelihood estimates of parameters for a fairly complicated multivariate distribution. The support of the distribution depends on its parameters so I need to include some ...
0
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0answers
49 views

Chi square: compare two different distribution

I try to compare two file with two different distribution of numbers. So i have random1.dat and random2.dat each one are vectors of more then 1000 rows. I saw from this question Doing a chi-square ...
3
votes
1answer
154 views

Determining the dimension of a probability distribution

Functions like Mean and RandomVariate clearly infer the dimension of the distribution passed to them. One can also usually ...
5
votes
3answers
740 views

Fast code to generate large random graph with fixed degree sequence

I'm trying to create a function so to generate large random graph with a fixed degree sequence $\{v_1,v_2,\dots,v_N\}$, where $N$ is the number of vertices in the graph. The Mathematica function that ...
2
votes
1answer
99 views

Determining sample size with no replacement for a given confidence and reliability when there are x failures observed during sampling?

I am trying to follow the procedure of a Sandia Labs report found here to determine the required sample size, for various population sizes, with no replacement for a given confidence and reliability. ...
3
votes
1answer
487 views

Categorical Distribution

Suppose I want to do calculations with a random variable $X$ that has a simple categorical distribution (a.k.a generalised Bernoulli distribution or discrete distribution). I was expecting to be able ...
0
votes
0answers
103 views

Probability Model

I have the following probability model: $(X_k|\text{ PastHistory}_{k-1}, \theta_0, \theta_1, \theta_2) \sim (\pi\cdot N(\theta_1+\theta_0\cdot X_{k-1},1)+(1-\pi)\cdot N(\theta_2+\theta_0\cdot ...
1
vote
1answer
250 views

Detecting a nonlinear edge in a 2D point pattern

Following an earlier post here, I have generated a point pattern on the unit square $[0,1]\otimes[0,1]$, which is described by a piecewise constant intensity function constructed so that (in ...
7
votes
3answers
771 views

How do I create a histogram with unequal bin widths?

I would like to create a histogram for human population by age, but the $2010$ census data I have available is for five uneven cohorts: ages $0$-$17$, $18$-$24$, $25$-$44$, $45$-$64$, and $65+$. My ...
0
votes
0answers
88 views

Compute (Co)Variance of Random Variable(s) Directly

Is there a direct command in Mathematica that computes the covariance between two random variables? Hence, instead of typing ...
2
votes
2answers
186 views

Time differences between code using user-defined probability distribution and code using built-in distribution

Why is the reponse time of of kernel significantly different when I use the first code rather than the second? Shouldn it not be the same? Is there any way that the response time can be made smaller ...
1
vote
1answer
53 views
0
votes
1answer
159 views

Convert probability example to a distribution

Consider a box which contains 30 balls. 10 red, 10 white and 10 blue balls. There will be picked 4 balls randomly, without putting the balls back to the experiment. My question is: How do I create a ...
2
votes
1answer
242 views

Compute Correlation between two binary variables

$X_1$ and $X_2$ are two binary stochastic variables with simultaneous probabilitydistribution: $$ \begin{matrix} &X_2=0&X_2=1\\ X_1=0&0.30&0.17\\ X_1=1&0.08&0.45 ...
2
votes
2answers
145 views

Conditioned Probability Task

I have this task with two questions I would like to compute in Mathematica. Suppose a pair of random variables $(X, Y)$ has a equal distribution on the following 7 points: $\begin{matrix} ...
13
votes
1answer
317 views

Randomness test suites that can be invoked from Mathematica

There are several test suites referenced at csrc.nist.gov designed to test a (pseudo-)random byte sequence for randomness, and discover possible skews, correlations, patterns, or other hidden ...
1
vote
1answer
234 views

Pseudo-code for rules of probability?

I am having a hard time in Stats understanding some basic rules of probability and set-theory, namely $P(A|B)$, $P(A\ \textrm{and}\ B)$ and $P(A\ \textrm{or}\ B)$ where $A$ and $B$ depend on each ...
3
votes
0answers
311 views

Is it possible to marginalize one or several parameters obtained from fitting procedure?

Statistical model analysis package has a few fitting functions. Their arguments are data points, fitting model and parameters in the fit. The result is a set of best values for parameters, which ...
5
votes
1answer
2k views

How do I display a histogram with normalized counts?

I have some data corresponding to real number distances: {200.04053, 200.232123, 156.3242,...}, and I would like to bin these values and display them as a histogram ...
20
votes
2answers
814 views

Efficient Generation of Random Variates from a Copula Distribution

I have a 7-asset portfolio for which I want to simulate daily log-deltas using a Student T copula. The marginal distributions are all either Stable or TsallisQGaussian. Using NMaximize, I have ...
3
votes
1answer
3k views

Filtering Lists in Mathematica [duplicate]

Possible Duplicate: Select/Delete with Sublist elements? I need help in filtering long lists of x,y coordinates.Lets use the following list as an ...
2
votes
2answers
137 views
3
votes
2answers
509 views

Total Variation Distance of probability matrix

How can I calculate the Total Variation Distance of a transition Matrix? is there any built in function? I've searched all documentation and haven;t found anything. ** More information: Let me try ...
5
votes
1answer
391 views

How do I get the critical value in statistical hypothesis testing?

What I am trying to do is to get the value of $\chi^2$ for given probability (let us say $\alpha$=0.01) and degrees of freedom (for example df=3). How do I get that? Inverse...Distribution functions ...
12
votes
1answer
1k views

Persistence length of a polymer chain

I'm trying to calculate the persistence length (Lp) of a polymer chain using Mathematica. The first and simplest method is to compare the EuclideanDistance between ...
1
vote
2answers
197 views

Expectation over a list with nested-mapped expressions

I need expected values of a list where the random variable to take expectations over should be an input into expressions defined earlier. I suspect Set[] and SetDelayed[] tripped me. (Or Map and ...
8
votes
3answers
1k views

Ηow to create an interpolated CDF from its samples?

I want to use a distribution I have only aggregate statistics on, namely its CDF sampled at certain points. I would like to keep it "nonparametric" (remain noncommittal on the parametric form), but I ...
12
votes
1answer
350 views

Just what kind of transformations can TransformedDistribution handle?

Why does the following command return an empty plot? ...