Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [nonlinear]

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327 questions
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What does 'highly non linear' mean?

I often read about a function being 'highly non linear'. In my understanding, there is "linear" and "non-linear", so what is this 'highly' about? Is there a formal difference from non linear? How is it defined?
Toby El Tejedor
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Nonlinear vs. generalized linear model: How do you refer to logistic, Poisson, etc. regression?

I have a question about semantics that I would like fellow statisticians' opinions on. We know models such as logistic, Poisson, etc. fall under the umbrella of generalized linear models. The model includes nonlinear functions of the parameters,…
Meg
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Advanced regression modeling examples

I'm looking for an advanced linear regression case study illustrating the steps required to model complex, multiple non-linear relationships using GLM or OLS. It is surprisingly difficult to find resources going beyond basic school examples: most of…
Robert Kubrick
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Nystroem Method for Kernel Approximation

I have been reading about the Nyström method for low-rank kernel aproximation. This method is implemented in scikit-learn [1] as a method to project data samples to a low-rank approximation of the kernel feature mapping. To the best of my knowledge,…
Daniel López
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what makes neural networks a nonlinear classification model?

I'm trying to understand the mathematical meaning of non-linear classification models: I've just read an article talking about neural nets being a non-linear classification model. But I just realize that: The first…
Alvaro Joao
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What is the best programmatic way for determining whether two variables are linearly or non-linearly or not even related

What is the best programmatic way for determining whether two predictor variables are linearly or non-linearly or not even related, maybe using any of the packages scipy/statsmodels or anything else in python. I know about the ways like plotting and…
ShyamSundar R
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If an auto-regressive time series model is non-linear, does it still require stationarity?

Thinking about using recurrent neural networks for time series forecasting. They basically implement a sort of generalized non-linear auto-regression, compared to ARMA and ARIMA models which use linear auto-regression. If we are performing…
Skander H.
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Why KNN is a non linear classifier ?

How do we decide if a classifier is linear or non linear ? What property/characteristic makes a classifier linear or non linear ? Eg: Why SVM is a linear classifier ? Why Logistic Regression is linear classifier even though it uses logistic…
mach
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Distinction between linear and nonlinear model

I have read some explanations about the properties of linear vs nonlinear models, but still I am sometimes not sure if a model on hand is a linear or a nonlinear one. For example, is the following model linear or nonlinear? $$y_t=\beta_0 +…
DatamineR
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Non-linearity before final Softmax layer in a convolutional neural network

I'm studying and trying to implement convolutional neural networks, but I suppose this question applies to multilayer perceptrons in general. The output neurons in my network represent the activation of each class: the most active neuron corresponds…
rand
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Explain steps of LLE (local linear embedding) algorithm?

I understand the basic principle behind the algorithm for LLE consists of three steps. Finding the neighborhood of each data point by some metric such as k-nn. Find weights for each neighbor which denote the effect the neighbor has on the data…
User1234321232
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Why is it important to make a distinction between "linear" versus "non-linear" regression?

What is the importance of the distinction between linear and non-linear models? The question Nonlinear vs. generalized linear model: How do you refer to logistic, Poisson, etc. regression? and its answer was an extremely helpful clarification of the…
Ashley Naimi
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3 answers

Strategy for fitting highly non-linear function

For analyzing data from a biophysics experiment, I'm currently trying to do curve fitting with a highly non-linear model. The model function looks basically like: $y = ax + bx^{-1/2}$ Here, especially the value of $b$ is of great interest. A plot…
onnodb
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Is autocorrelation in a supervised learning dataset a problem?

Imagine the following problem. I have weekly snapshots of price data of K items, as well as of various features/predictors. I want to predict how much the price will change 2 years from now. I assemble my dataset as follows: each row consists of…
rinspy
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What are criteria and decision making for non-linearity in statistical models?

I hope that the following general question makes sense. Please keep in mind that for the purposes of this particular question I'm not interested in theoretical (subject domain) reasons for introducing non-linearity. Therefore, I will formulate the…
Aleksandr Blekh
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