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]
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Regression plane coefficients
I apologize in advance if this question is too simple, but I am new to the topic. I am trying to calculate the regression plane coefficients for a vector of 3D points. So far I have been able to calculate A and B in the general plane equation:
z=Ax…
Giant Cloud
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Get coefficients from locfit model
I have fitted data with local regression through the package "locfit" and I would like to get the coefficients, but I have not been able to get them.
I have run the function "locfit" with ev=none(), because I want a semiparametric fitting.
I have…
Citizen
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How to make a regression model efficient?
I am using the first three column as three different independent variables and trying to find the value of dependent variable which is in the fourth column. Here is a piece of data and results. With these details, I am trying to formulate an…
Image Check
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How to load/save a nonlinear model in MATLAB
I've used fitnlm() in a loop to create a cell array of nonlinear models.
and saved said cell array
like this:
for i=1:N
modelfun = @(b,x)model_func_3(b,x,n);
inital_b = rand((n+1)*(n+2)/2,2)
model_array{i} =…
Daniel Roth
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Evolve dynamic system without an analytic expression for time derivative by solving for all the time-changing values at the same time
I have a dynamic system where I have an expression for the residual of the time derivate but not an analytic expression for what the time derivative actually is: sum(da_i/dt) ** 2 = f(a). I can solve this by performing an optimization at every time…
kilojoules
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predicting values witn non-linear regression
My non-linear model is the following:
fhw <- data.frame(
time=c(10800, 10810, 10820, 10830, 10840, 10850, 10860, 10870, 10880, 10890),
water=c( 105, 103, 103, 104, 107, 109, 112, 113, 113, 112)
)
nl <- nls(formula = water ~…
userUnknown
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R: Confidence intervals on non-linear fit with a non-analytic model
I need to fit x-y data with a model, which is non-analytic. I have a function f(x) that calculates the model for each x numerically, but there is no analytical equation. For the fit, I use optim in R. I minimise RMS between the model and the data.…
Marek Gierliński
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Why am I getting a System.ArithmeticException in this example doing a non-linear regression to a Gaussian
I am porting some code that I prototyped in Matlab to C# and need perform do a non-linear regression of a Gaussian to my sample data. I am currently trying Accord.Net and came up with the code below following the example here.
Unfortunately I am…
packoman
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Automatic model creation, for model selection, in polynomial regression in R
Let's imagine that for a target value 'price', I have predictive variables of x, y, z, m, and n.
I have been able to analyse different models that I could fit through following methods:
Forward, backward, and stepwise selection
Grid and Lasso
KNN…
Behrouz Beheshti
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Nonlinear model (with country and time fixed effects)
I try to estimate the above nonlinear model by Stata. Unfortunately, I am not comfortable with Stata. Can anyone help me about writing the above function in Stata?
How can we write regional dummy, time fixed effect and country fixed effect in nl…
Mecit Yildirim
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3 answers
How do you fit parameter values in nonlinear model using R or Python
I've got a function and a set of points. The function is:
s(t) = m*g*t/k-(m*m/(k*k))*(exp(-k*t/m)-1)
where m and k are the parameters in question.
I have the data for (t, s(t))
I need to find the best m and k to fit this equation to my data, and I…
TotalNewb2017
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Simple Regression Prediction Algorithm in JavaScript
I am trying to do a simple forecast of future profit of an organization based on the past records by using regression. I am following this link. For testing purpose, I have changed the sample data and it produced these results:
My actual data will…
QWERTY
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Margins package commands taking too long to run
I wish to evaluate marginal effects of variables in a logit regression using a dataset like this (with 40k observations):
d1<- structure(list(dummy.eleito = c(1, 0, 0, 0, 0, 1, 1, 1, 1, 0),
dummy.tratamento = c(1, 1, 0, 0, 0,…
Arthur Carvalho Brito
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Issue in kNN regression using R?
I am trying to do prediction using kNN regression in R. I have two variable (X,Y) in excel table format (total 800 data-sets in each variable). My aim is to predict the value of Y (present in Test table) So for that I have written code in R as…
Ankita
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why random forest regression return a very bad result?
I'm trying to use randomforestregressor() in scikit_learn to model some data.After processing my raw data, the data I applied to randomforestregressor() is as follows.
The following is only a little part of my data. In fact, there are around 6000…
Nick Gao
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