Tagged Questions
1
vote
1answer
101 views
Safe values of $\mu$ and $\sigma$ when randomly sampling from a Log-Normal Distribution?
I believe I'm obtaining overflow errors when randomly sampling from a log-normal distribution with the command:
RandomVariate[LogNormalDistribution[μ, σ], 1]
...
1
vote
0answers
53 views
integral of inverse distribution function
Can Mathematica solve the following problem?
The parameter of interests is $\alpha$. Let $G(y)$ be the distribution function of $y$. (e.g. $G$ is a lognormal distribution function with given ...
2
votes
1answer
145 views
Calculate variance of random walk?
How can I symbolically calculate the variance of the following random walk in Mathematica?
Given several discrete random variables such that $p(Z_i=1-2k)=p$, where $k$ is a small real number, and ...
0
votes
1answer
230 views
Solving derivative of cumulative normal distribution log likelihood
I am a newbie and I'm trying to use Mathematica to obtain the symbolic Maximum Likelihood Estimation for a cumulative normal distribution. So far I have reached the step where I have the derivative of ...
3
votes
1answer
120 views
Expectation of CauchyDistribution
I've noticed this strange behavior and I'm wondering if it's a bug.
I define a Cauchy distribution:
c = CauchyDistribution[0, 1];
If I evaluate ...
13
votes
1answer
288 views
RandomVariate returns values outside the support of a PDF
Let $X$ be a random variable with pdf:
dist = ProbabilityDistribution[1/(Abs[x]*Log[Abs[x]]^2), {x, -E^-2, E^-2}]
Here are some pseudo-random drawings from it:
...
0
votes
1answer
157 views
Trying to plot this probability
Can anyone help me plot this?
log P(X >= x) = alpha logx
x=0.001 + k(0.001)
k= 0, ..., 100
I can't figure out the coding for this.. I've been trying this for a while, and can't seem to figure it ...
8
votes
3answers
632 views
How to generate a RandomVariate of a custom distribution?
I'm trying to generate a pseudorandom variate out of a custom distribution. Suppose I want define a custom distribution, and for the sake of simplicity I define a Poisson distribution (the ...
12
votes
1answer
386 views
How to compute the inverse CDF properly?
I want to compute the CDF and inverse CDF of the hyperbolic distribution:
α = 2; β = 3/2;
x = -3;
u = N[CDF[HyperbolicDistribution[α, β, 1, 0], x], 30]
The ...
12
votes
2answers
510 views
Obtaining joint distributions and conditional distributions using Mathematica
I have two multivariate Gaussian distributions $p(x)$ and $p(z)$ with mean vectors $m_x$ and $m_z$, and covariance matrices $\Sigma_x$ and $\Sigma_z$.
my model is a simple linear model $x = W z+n$ ...
7
votes
1answer
308 views
Probability and distribution from actual data
Let's say I have some data from a real world system:
...