Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [multivariable]

40 questions
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3 answers

Does adding more variables into a multivariable regression change coefficients of existing variables?

Say I have a multivariable (several independent variables) regression that consists of 3 variables. Each of those variables has a given coefficient. If I decide to introduce a 4th variable and rerun the regression, will the coefficients of the 3…
Lukas Pleva
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Computing best subset of predictors for linear regression

For the selection of predictors in multivariate linear regression with $p$ suitable predictors, what methods are available to find an 'optimal' subset of the predictors without explicitly testing all $2^p$ subsets? In 'Applied Survival Analysis,'…
shabbychef
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Finding marginal densities of $f (x,y) = c \sqrt{1 - x^2 - y^2}, x^2 + y^2 \leq 1$

As the title says, I'm looking for the marginal densities of $$f (x,y) = c \sqrt{1 - x^2 - y^2}, x^2 + y^2 \leq 1.$$ So far I have found $c$ to be $\frac{3}{2 \pi}$. I figured that out through converting $f(x,y)$ into polar coordinates and…
Jarrod
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What are the software limitations in all possible subsets selection in regression?

If I have a dependent variable and $N$ predictor variables and wanted my stats software to examine all the possible models, there would be $2^N$ possible resulting equations. I am curious to find out what the limitations are with regard to $N$ for…
Levon
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From Marginal Exp-Norm Distributions to What Conditionals and Joint?

I have (trivariate: multivariate with three variables) data that appears to be good empirical and reasonable theoretical fit for a (univariate) convolution of an exponential and a normal distribution (some times called exp-norm or exGauss…
MrDrFenner
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Readdressing the semantics of multivariate and multivariable analysis

There was a post once upon time dealing with the differences of multivariable and multivariate regression. I have seen the relevant post here. However I am having this debate with a colleague and while I agree with the information of this post, my…
user4673
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How to determine how many variables and what kind of variables a table of data has?

Here's an example regarding what I'm lost on. In the past I've just found myself counting columns to determine how many variables a table has, but I've realized that's totally insufficient. For example, I look at the following table and would think:…
Charles Clayton
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Estimating probability distribution function of a data stream

I have a very large number of observations. Observations arrive sequentially. Each observation is an $n$-dimensional vector (with $n \ge 100$), is independent from the others and is drawn from the same unknown distribution. Is there an optimal…
gappy
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How to add a third variable to a bar plot?

I'm trying to find the best way to show the following data: Course Grade Avg Diff. Semester EECE 253 - Circut Analysis II 64 71 -7 Two MATH 253 - Multivariable Calculus 63 68 -5 …
Charles Clayton
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Multivariate Interpolation Approaches

Is there a good, modern treatment covering the various methods of multivariate interpolation, including which methodologies are typically best for particular types of problems? I'm interested in a solid statistical treatment including error…
Christopher D. Long
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Determine linear relationship between input and output with multiple input variables

Say that your input variables are in $\mathbb{R}^2$ with a univariate output variable. Say that you want to determine whether the output variable is a linear combination of the input variables. If you just had one input variable you could easily…
user1893354
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How to report data when there is interaction

I did a multivariable logistic regression analysis to estimate the effect of an exposure (E) on an outcome while adjusting for confounders. I investigated interaction and discovered a significant interaction between the E and one of the confounders.…
TripleA
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Estimating entropy of multidimensional variable through dimension reduction

Is there anything inherently wrong with trying to estimate the entropy of a multidimensional random variable by first transforming it (by some method) into a single-dimensional variable?
user3557985
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Nearly constant time series

I want to analyse temporal interactions of some time series by means of the Box-Jenkins approach to find out which time series are predictors of another one (with the help of prewhitening and computing cross correlations for some lags) and finally…
eski
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Dataset for multi class perceptron

I am developing a multi-class perceptron algorithm and was wondering if there are any datasets that could be used to test a multi-class perceptron? - A dataset where the classes are linearly separable and have at least 100 or more instances for…
KungPaoChicken
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