For questions related to the mathematical concept of a random variable (in the context of AI).
Questions tagged [random-variable]
22 questions
5
votes
1 answer
What does the notation $\mathcal{N}(z; \mu, \sigma)$ stand for in statistics?
I know that the notation $\mathcal{N}(\mu, \sigma)$ stands for a normal distribution.
But I'm reading the book "An Introduction to Variational Autoencoders" and in it, there is this notation:
$$\mathcal{N}(z; 0, I)$$
What does it mean?
picture of…
Peyman
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3
votes
1 answer
Is learning possible without random thoughts and actions?
In my view intelligence begins once the thoughts/actions are logical rather than purely randomn based. The learning environments can be random but the logic seems to obey some elusive rules. There is also the aspect of a parenting that guides…
dankilev
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2
votes
1 answer
Which of the following probability distribution is generating an iid dataset?
Let $X_1, X_2$ be two discrete random variables. Each random variable takes two values: $1, 2$
The probability distribution $p_1$ over $X_1, X_2$ is given by
$$p_1(X_1=1, X_2 = 1) = \dfrac{1}{4}$$
$$p_1(X_1=1, X_2 = 2) = \dfrac{1}{4}$$
$$p_1(X_1=2,…
hanugm
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vote
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What kind of distributions can be used to model discrete latent variables?
If we take the vanilla variational auto-encoder (VAE), we $p(z)$ is a Gaussian distribution with zero mean and unit variance and we approximate $p(z|x) \approx q(z|x)$ to be a Gaussian distribution as well, for each latent variable $z$.
But what if…
piccolo
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1
vote
1 answer
How to compute an estimate of the expected value of a stochastic random variable in Reinforcement Learning?
In the section on LSTD in SuttonBarto's book on RL, there is a proof on convergence of semi-gradient TD(0) using a linear function approximator.
Later on they estimated A and b as
I was under the impression that to calculate an estimate of…
user75923
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1
vote
1 answer
Can I always interpret features as random variables in machine learning safely?
Consider the following statements from Chapter 5: Machine Learning Basics from the book titled Deep Learning (by Aaron Courville et al.)
Machine learning tasks are usually described in terms of how the
machine learning system should process an…
hanugm
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1
vote
1 answer
What are the iid random variables for a dataset in the GAN framework?
I am trying to understand why mean is used for expectation in training Generative Adversarial Networks.
The answer tells that it is due to the law of large numbers which is based on the assumption that random variables are independent and…
hanugm
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1
vote
1 answer
Is it abuse of notation to use tilde operator in this context?
The following is a way to use tilde (∼) in context of random variables or random vectors.
In statistics, the tilde is frequently used to mean "has the
distribution (of)," for instance, $X∼N(0,1)$ means "the stochastic
(random) variable $X$ has the…
hanugm
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vote
0 answers
Is it possible to use (infinite cardinal) random variables during implementation?
Random variables can be broadly classified into three types:
random variables whose range is finite,
random variable whose range is countably infinite and
random variables whose range is uncountable.
Random variable is called discrete if its…
hanugm
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1
vote
0 answers
What machine learning model should I use for a random dice-based game?
Consider a game like Pig (https://en.wikipedia.org/wiki/Pig_(dice_game)), but with a few additions: namely functions of both player's score and turn number that have unique impacts on scoring.
What machine learning model should I use to try and get…
robert
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1
vote
1 answer
In the definition of the state-action value function, what is the random variable we take the expectation of?
I know that
$$\mathbb{E}[g(X) \mid A] = \sum\limits_{x} g(x) p_{X \mid A}(x)$$
for any random variable $X$.
Now, consider the following expression.
$$\mathbb{E}_{\pi} \left[ \sum \limits_{k=0}^{\infty} \gamma^{k}r_{t+k+1} \mid s_t = s, a_t = a…
hanugm
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1
vote
1 answer
Why is this variable in equation 2 of the SQAIR paper a random vector of $n$ ones followed by a zero?
I've been reading the SQAIR paper lately, and the mathematics involved seems a bit complicated.
Some background, about the paper: SQAIR stands for Sequential Attend, Infer, Repeat - the paper does generative modelling of moving objects. The idea of…
stoic-santiago
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vote
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What is the point of converting conditional probability to factor for Variable Elimination?
I have this slide from my AI class on using a Bayes network to compute a conditional probability. I don't really understand the point of converting the conditional probabilities to factors (besides the fact that it looks weird to marginalize or…
Gooby
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votes
0 answers
Why neural networks model statistical patterns
I've tried to come up with a simple connection between statistics and deep learning. One question is:
In very simplified terms, why do neural networks model probability distributions?
What I expect is an authoritative answer as to how this chain…
Minsky
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0
votes
1 answer
Independence of random variable in Gaussian Process context
From Bishop's Pattern Recognition and Machine Learning:
$t_n = y_n + \epsilon_n$, where $\epsilon_n$ is a random noise variable whose value is chosen independently for each observation $n$. Consider
$$p(t_n|y_n)= {\cal…
piero
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