In statistics, nonlinear regression is a form of regression analysis in which observations are modeled by a function which is a nonlinear combination of the model parameters and depends on one or more independent variables.
Questions tagged [non-linear-regression]
732 questions
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nls2 fitting in R (get back calculated values)
I am using the nls2 package to do a fit. The fit is correct but how do I get back just the calculated values of the predicted variables?
The formula:
fit <- nls2(Trans ~ t - (h * W ^ 2 / ((WLn - x0) ^ 2 + W ^ 2)),
data = siteData,
start =…
user3646105
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How to force using hinge function for earth implementation of MARS in python
I am currently facing a problem using earth implementation of MARS in python.
When I fit my data like this :
model=Earth()
model.fit(data1,data2)
print model.summary()
It gives me this :
Basis Function Pruned Coefficient
(Intercept) No …
user3967210
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R Nonlinear regression
I need a help with a curve fitting problem. I am also quite new to R. I have some data ( 3 pairs of type (x,y)), and need to apply a Nonlinear regression.
Basically, I have a function f(x,a,b,c,d,e,f) - x and 6 other parameters. I want to find a…
Vaidotas
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4 parameter non-linear regression curve fit for ELISA data in SPSS?
I’m currently undergoing studies and for one of my subjects I’ve performed an Elisa and got results for salivary cortisol levels using the salimetrics cortisol enzyme immunoassay kit. It says in the protocol to use a 4-parameter non-linear…
Wyatt Schubel
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How to find the impact of one variable on the other when there seems to no correlation between them?
can we predict growth percentage in sales of an item given the change in discount(positive or negative number) from the previous year as a predictor variable. There seems to be no correlation between these. How to solve this problem using machine…
sairishi
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2 answers
Gaussian Process Regression: tune hyperparameters based on validation set
In the standard scikit-learn implementation of Gaussian-Process Regression (GPR), the hyper-parameters (of the kernel) are chosen based on the training set.
Is there an easy to use implementation of GPR (in python), where the hyperparemeters (of the…
Jakob
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Is this code for nonlinear regression in MATLAB right?
I am trying to solve this example in MATLAB but I can't get the right answer.
i use this code
clear all;clc;
x=[4 2.25 1.45 1.0 0.65 0.25 0.006];
y=[ 0.398 0.298 0.238 0.198 0.158 0.098…
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Is Random Forest a linear or non linear regression model
As decision trees are non linear models so Random Forest should also be nonlinear methods in my opinion. But at some articles i have read otherwise. Can anyone explain how are they nonlinear or not .
or in other words Is Random Forest for linear or…
vaibhav
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Linear and non-linear regression concerns
I'm trying to do this polynomial regression using the scatter plot, and I have two concerns:
The red line, which is the polynomial regression appears wrong to me when compared with the plots by the data values
How can I calculate the r-square for…
Tayzer Damasceno
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Fit nonlinear regression pandas
I have a dataset Coronavirus cases per day with dates
And then I made this plot, Cases vs Days, which is a curved line. Graph
I would like to fit a curved line that predicts future cases. But how to do that? I'm new and I'm used to linear…
mikal
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1 answer
Calculate the predicted model accuracy in python for regression problem
I want to calculate my model accuracy for rainfall forecasting. I already calculated MAE, RMSE, MAPE for rainfall forecasting. But want to know the total model accuracy, for instance, my model is predicting 96% accurate results. How can I do this in…
user7657378
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Solving large system of non linear equations
I'm trying to solve a system of 30 non linear equations (unknown variables sit inside exponential functions). I have exactly 30 variables and 30 unknowns. I'm trying to use scipy.optimize.fsolve but it is essentially not doing anything. I'll post my…
CStarAlgebra
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X and Y are not correlated, but Y is predictor of Xin random forests classifier. How to represent this using statistics and machine learning?
X and Y are not correlated (0.3); however, when I place X in random forests classifier predicting Y, alongside two (A, B) other (related) variables, X and two other variables (A, B) are significant predictors of Y. Note that the two other (A, B)…
Rapa
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Python Regression of Categorical data with interactions
I have found how people do linear regressions on Python using sklearn and doing reg.fit() with their data, but this only lets you do it if you're looking for a regression like
y = Ax1 + Bx2 +Cx3 etc
But what if I had categorical data that had some…
Yo Jo
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How can I fit a nonlinear line in R?
I am new to R and can't find an answer to this (seemingly) simple question. I have been searching for a couple of days, and did read a couple of papers and the help pages.
I have been able to plot one line (in red).
I want to plot another line…
SachaKip
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