Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [mathematica]

Mathematica is a software package for symbolic mathematical computations.

Mathematica is a software package for symbolic and numerical computation. It has a graphical user interface with high quality graphics output. It is used for numerical, mathematical, statistical and other calculations.

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What's the distribution of $(a-d)^2+4bc$, where $a,b,c,d$ are uniform distributions?

I have four independent uniformly distributed variables $a,b,c,d$, each in $[0,1]$. I want to calculate the distribution of $(a-d)^2+4bc$. I computed the distribution of $u_2=4bc$ to be $$f_2(u_2)=-\frac{1}{4}\ln\frac{u_2}{4}$$ (hence…
corey979
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Why do Excel and WolframAlpha give different values for skewness

for the following 3 values 222,1122,45444 WolframAlpha gives 0.706 Excel, using =SKEW(222,1122,45444) gives 1.729 What explains the difference?
Scott Weinstein
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Mathematica's random number generator deviating from binomial probability?

So, let's say you flip a coin 10 times, and call that 1 "event". If you run, 1,000,000 of these "events", what is the proportion of events that have heads between 0.4 and 0.6? Binomial probability would suggest this to be about 0.65, but my…
Tim McKnight
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PDF of a sum of dependent variables

This is a direct continuation of my recent question. The thing that I actually want to get is the distribution of $a+d+\sqrt{(a-d)^2+4bc}$, where $a,b,c,d$ are uniform in $[0,1]$. Now, the distribution of $(a-d)^2+4bc$ was successfully computed in…
corey979
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Symbolic computer algebra for statistics

What functionality should exist in a CAS that was specifically geared toward Statistics? Symbolic algebra systems like Mathematica and Maple are often used for calculus, logic, and physics problems but are rarely used for statistics. Why is…
MRocklin
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Comparing two datasets with same variable

thanks in advance for anyone taking the time to read/answer this. I am comparing a ground-sourced dataset versus a satellite-sourced dataset for weather conditions, such as temperature. Both sets are time series data (ground takes a reading every 15…
sanjayr
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Wolfram Mathematica, MATLAB or something else?

I have only a little experience in math calculation tools. So please don't be strict if my question is not well defined :) Which tool (Wolfram Mathematica, MATLAB or something else) is better to use for statistics? Where can I find quickstart guides…
Mihran Hovsepyan
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software library to compute KL divergence?

Are there any software libraries that compute KL divergences in closed form, that also give the derivatives of the KL divergence wrt the distributions' parameters? I'm using Julia, so it's particularly straightforward for me to call Julia, Fortran,…
Jeff
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Book recommendation for undergraduate stats with Mathematica

Having just completed my Bachelor with a major in math and physics, I am aware that due to my chosen specialisation, I lack a good training and exposure in statistics beyond the first year. Could anyone recommend a good book on statistics where the…
Physkid
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Chi-square independence in political sciences

I've been assigned to do a cross-class project between political science and math about the behavior of voters in a democratic state. More specifically, I'm focusing on a party from a national election in 2007, where I have made a table consisting…
Frederik Brinck Jensen
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Visualizing a 3D dataset of proportions

I'm looking for visualization ideas for the following data: I have a $10\times 12$ grid of points $(x_i,m_j)$, where the $x_i$ are a set of distances (e.g. 1,2,..., 10 m) and the $m_j$ are the 12 months. At each $(x_i,m_j)$, I have 4 values…
amet
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Maximum Uncertainty in Normal Distribution

While reading Goodfellow's Deep Learning Book, I came across the below fact about Normal Distribution. I am not sure I have understood what led to this conclusion, Can someone help with it? "Out of all possible probability distributions with the…
umesh
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How do I calculate the Bayes error of a multivariate normal Bayesian classifier?

I have a 4 dimensional feature and each of them are independent normal distributions. I want to calculate the bayesian error associated with this classifier. The covariance matrix and the mean have been given for multivariate normal distribution. I…
karthik A
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How to calculate confidence and prediction bands for a linear regression using Mathematica?

I need to calculate confidence and prediction bands for a linear regression that is in the general form of $y=ax$, where $a$ is the multiplier and $x$ the variable. I found a code in http://demonstrations.wolfram.com/ConfidenceAndPredictionBands/ ,…
K-1
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Characterizing periodicity level of signal

What are some good ways of quantitatively characterizing the periodicity level of an approximately periodic $f(t), t \in \mathbb{R}$ signal? I need this to tell if the output of some system is periodic or not, and to be able to decide the output of…
Szabolcs
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