Questions tagged [julia]
Julia is a high-level, high-performance dynamic programming language for technical computing, with syntax that is familiar to users of other technical computing environments.
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Calculating descriptive stats for aggregate/binned data [duplicate]
I have several datasets that I wish to analyse and summarize - and I'm starting with the basic median, and percentile/quartiles to begin with (unless there are other approaches I should be considering)...
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Training a physics informed neural network (PINN) in Julia using numerical gradient approximations
i am currently working on a small project which involves solving a pendulum differential equation
$$a \ddot{x} + b \dot{x} + x = 0$$
The idea is to use a physics informed neural network which has two ...
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PCA for 3D Lidar data
I'm trying to work with Lidar data to classify road. I'm wondering how to use pca (or something else?) to identify if region has connectivity > threshold then label the region to be road? Would ...
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Subspace method fails at identifying parameters in a state space system
I am trying to infer the parameters of a linear multivariate time-invariant state space system using a subspace method. However, the inferred parameters do not match the ground-truth parameters used ...
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Fast package for quadratic form using an inverse of a kernel
The following situation comes up a lot when working with Gaussian processes.
Let's say we have a vector $h \in \mathbb{R}^n$.
We are in the setting where $n$ is small enough to a fit a float array of ...
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How is highest posterior density interval estimated in this code snippet?
I found the following (Julia) implementation for estimating the highest posterior density interval from a posterior sample (link). Below, I turn it into pseudocode for simplicity.
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Agent based modeling: binding 2 agents together to form a H2 molecule in NetLogo (or Agents.jl)? [closed]
Note: I got the message:
This question appears to be off-topic because it is not about probability, statistics, machine learning, data analysis, data mining, or data visualization.
Agent based ...
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How to formulate probability P(X) into a logistic regression?
This might be quite basic but I'm struggling.
I'm trying to take a published ecological model and implement it in the Turing.jl package using Julia. Say I have a ...
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Find first Principal Component (and loading) using a fast iterative algorithm without covariance matrix
I have a matrix $X$ and I would like to find its first principal component and the corresponding loadings. I would like to do this without computing the covariance matrix of $X$. How can I do so?
This ...
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Bias in unbiased pseudo-marginal estimation?
In the Pseudo-marginal Metropolis-Hastings algorithm exact sampling of a posterior distribution is performed when using an unbiased estimate of the marginal likelihood. However, I am having problems ...
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proposal value between the generated data and the accepted previous proposal
I have a question here that has been confusing me these two days. So in mcmc hasting metropolis if a proposal value was accepted which means tha it's going to be the current value after that ...
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mathematical difference between two functions used in scaling data and viewing distribution
I am trying to understand the difference between f(x) and g(x) below. I am not a mathematician or statistician, so please bear ...
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Coordinate Descent in Ordinary Least Squares not converging
As a warm-up to writing my own elastic net solver, I'm trying to get a fast enough version of ordinary least squares implemented using coordinate descent.
So if $b = Ax$, I want to find $x$ that ...
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QQ-Plots in Julia via Plots.jl? [closed]
I am trying to make QQ-Plots in Julia, but the only solution I could find is this old example using Gadfly. Given that it's being deprecated, I wanted to know if anyone knew of a solution for making ...
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Explaining the numbers in a decision tree
Using the famous Iris data set with Julia decision tree classifier I get the following tree.
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Unexpectedly slow convergence when classifying MNIST digits with a Neural Network
I recently finished my implementation of a multilayer artificial neural network in Julia; I train it with SGD (no momentum, no decay, no regularization, just basic SGD), computing the gradient by ...
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JuliaOpt Empirical Likelihood Estimation
I am trying to perform an empirical likelihood estimation in a regression setting using JuliaOpt (Convex or JuMP) and ran into difficulties using either API.
The problem:
Empirical likelihood for ...
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Large Sample Properties Least Square Estimator
I am trying to understand the properties of the least squares estimator. In particular the Gauss-Markov theorem states that the estimator is independent from the distribution of the error term.
Thus ...
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Non-Linear Least Squares Sine Frequency Estimation in julia
I am trying to estimate an artificial non-linear maximum likelihood problem which works fine as long as there is no frequency in a sine function to estimate.
I am using julia Optim and Distributions ...
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Julia: Taking stock of how it has been doing
I came across a 2012 question that had a very good discussion about Julia as an alternative to R / Python for various types of Statistical Work.
Here lies the original Question from 2012 about Julia'...
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How can I sample multivariate binary variables such that sum of them follows a poisson distribution?
Edit:
Since the original question was confusing as whuber pointed out, let me rephrase the question with a Poisson distribution instead of a gamma distribution.
The energy term of a Poisson ...
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Does Julia have any hope of sticking in the statistical community?
I recently read a post from R-Bloggers, that linked to this blog post from John Myles White about a new language called Julia. Julia takes advantage of a just-in-time compiler that gives it wicked ...