Questions on the use of Mathematica to construct models for approximating empirical data.

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1
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1answer
90 views

package for calculating exponent of power law distribution

There are some packages to fitting power law to empirical date in "R", "matlab", "python" Here with maximum likelihood method As it said here. Does it exist similar package in Mathematica?
7
votes
3answers
141 views

Locally Weighted Linear Regression

I am following the online Stanford Course in Machine Learning and I am trying to implement the algorithms on the fly in Mathematica. Currently, I have issues with minimizing the Locally Weighted ...
0
votes
0answers
31 views

Use “FindFit” for Multi-variable Polynomial Fit

I'm interested in defining three input vectors: $L=\{L_{1}, \ldots, L_{N} \}$ $W=\{W_{1}, \ldots, W_{N} \}$ $Q=\{Q_{1}, \ldots, Q_{N} \}$ and I'm hoping to be able to input a number for each of ...
1
vote
1answer
193 views

Fitting data to an Normal Inverse Gaussian distribution

I am using data which I suspect is distributed according to the Normal Inverse Gaussian distribution (NIG). The literature says that the 4 parameters of the NIG distribution can be estimated from the ...
8
votes
2answers
147 views

Using StepMonitor/EvaluationMonitor with DifferentialEvolution in NMinimize

My question about tracking the progress of a minimisation/fitting process is two-fold: 1. The first part of my question can be considered a slight duplicate/follow-up of this question. There the OP ...
-3
votes
1answer
44 views

importing mortality rates [closed]

In[1]=dataFrance = Import["G:\french female death rates.xlsx"] Out[1]={{{""}, {""}, {""}, {""}, {""}, {""}, {""}, {""}, {""}, {""}, {"0 \ 0.003531 "}, {"1 0.000312 "}, {"2 0....
1
vote
1answer
71 views

forecasting for mortality using a logistic regression

I need to know how to do a forecasting for mortality using a logistic regression, can somebody help? ...
3
votes
1answer
78 views

Filtering Background with resonance or Peaks

I have some data, the blue curve which I want to filter out the background to get a flat signal with dips(Idea is to divide signal (except the dips) by the background). The orange curve is my best ...
0
votes
1answer
59 views

How to force a Range on Fit?

I have 1001 points between {x,-5, 5}. I wanted to fit a polynomial over the data but when i try: Fit[Flatten[data], {0, x, x^2, x^4, x^5, x^6}, x] ... the range ...
6
votes
2answers
204 views

How to measure accuracy of prediction distribution?

I have been trying to come op with a way to test if my dataset follows a Poisson distribution. Normally one would use the DistributionFitTest function, but here is ...
3
votes
2answers
263 views

Mathematica Interpolation or approximation

I have lists of points X and Y. {1212,1216,1217,1219...}, {1,2,3,4,5,6...} I combine ...
3
votes
1answer
61 views

Looking for a convenient way to replace a large data sample with an analytic approximation

Suppose that data is a large data sample, and that Histogram[data] produces a very smooth-looking distribution. Since ...
2
votes
1answer
133 views
1
vote
1answer
71 views

NonlinearModelFit memory problem

I have a problem while trying to make a nonlinear fit of the following data: qn = NSolve[Tan[q] == 3*q/(3 + 1870715*q^2) && 0 < q <= 65, q] ...
3
votes
0answers
53 views

PearsonChiSquareTest for count/frequency data?

I read with interest a previous question on the PearsonChiSquareTest from a few years ago, and one answer was very helpful: Performing a chi-square goodness of fit ...
1
vote
2answers
66 views

Nonlinear fitting of a Gaussian beam model

I am having some troubles with the NonlinearModelFit function. However hard I try, I cannot get a nice fit curve for the data points. I know the parameter "a" is about 15*10^-6 but even if I plug in ...
0
votes
0answers
37 views

Is it possible to get the error estimates of predicted values computed by FindMinimum using the Levenberg Marquardt method?

I use the LevenbergMarquardt method of the FindMinimum function to minimize a residual function (mathematical-optimization). This residual function is computed from experimental data and the solution ...
2
votes
3answers
170 views

Use NMinimize instead of FindFit for constrained search (of coefficients)

(My problem is more complex, but let us formulate it through this example) I am trying to find the best polynomial approximation to the following function ...
2
votes
0answers
107 views
0
votes
1answer
43 views

Independent test of residuals, absolute member equal zero

Does Mathematica offer any test for confirm independence of residuals? except DurbinWatsonD. And I would like to ask how to make some test in regress function which tests absolute member equal zero. I ...
4
votes
2answers
428 views

NonlinearModelFit: fit a vector-valued function to a data vector

I have a vector of data points: data = 10 Sin[#/10] + RandomVariate@NormalDistribution[] & /@ Range[200]; And I have model that provides the complete ...
9
votes
3answers
186 views

Linear fit with conditional noise distribution

I need to fit a linear model of the form $y_i = a · x_i + b + e_i$. The $e_i$ are independent noise from a distribution that depends on $x$ as well as on global parameters of the data; however, the ...
5
votes
1answer
214 views

Modeling of soccer results using GeneralizedLinearModelFit

I am trying to recreate the regression in "Analysis of sports data by using bivariate Poisson models," which can be found here, http://tolstoy.newcastle.edu.au/R/e8/help/att-6544/karlisntzuofras03.pdf....
14
votes
2answers
283 views

Fitting Stradivari's scroll

How can I find the simplest curve that gives me a scroll like this? This is where I am at the moment and doing it by hand is becoming more and more cumbersome. First, take a drawing of the scroll ...
4
votes
1answer
92 views

Finding NonlinearModelFit of multiple data sets with the same parameters and in two dimensions

I have multiple sets of data (between 3 and 6 depending on the cases) dependent of space, time, and some parameters. The data are the response of a harmonic oscillator under a non-trigonometrical ...
0
votes
0answers
51 views

How to fit a plot with error bar as weight?

I try to fit a line which can fit through the points considering the error weight of each coordinate. Is it possible to do in Mathematica? I can only find Fit function which did not do what I really ...
1
vote
0answers
72 views

NonlinearModelFit with constraints error estimate integrity [closed]

I use NonlinearModelFit with additional constraints on the fitting parameteres. When I use "ParameterErrors" or ...
34
votes
3answers
841 views

What is behind experimental function: FindFormula?

In version 10.2 there is a new experimental function: FindFormula[]. I suspect that a genetic programming algorithm (symbolic regression) is behind this new ...
0
votes
2answers
121 views

A case of complicated fitting of multiple datasets

I've stumbled upon a difficulty while trying to do some fitting which may be called sorta complicated. I'll try to introduce my problem step by step. To begin with, I have a number of datasets ...
3
votes
3answers
107 views

Fitting problem

I have two points stored in data: data = {{0.0166667, 2.86927*10^-12}, {0.0333333, 1.12725*10^-11}}; ...
0
votes
0answers
48 views

Fitting 6 differential equations to 6 sets of data

I am using the newest Mathematica and I am trying to fit a set of 6 linear differential equations to a set of experimental data for each of the six variables. I am a baby beginner at this and could ...
1
vote
2answers
90 views

List argument for NonlinearModelFit

If I have a function of list argument (presumably with large number of entries), how can I pass it to NonlinearModelFit? I don't want to pass it by pattern checking ...
0
votes
2answers
105 views

Find min-max for slope in linear fit

I have a following data which follows a linear model with intercept zero, i.e. $$y = mx $$ ...
1
vote
1answer
93 views

Sum to Zero Constraint in GeneralizedLinearModelFit

Is there a way to impose a constraint on a generalized linear model fit in Mathematica? In R, when using the glm() function, you can set options(contrasts=c('YY.sum', 'ZZ.sum')). Is there something ...
0
votes
0answers
69 views

Exact meaning of `VarianceEstimatorFunction`

After reading the documentation, it's still unclear for me what VarianceEstimatorFunction does when fed with two arguments: ...
1
vote
0answers
35 views

Fitting Data when both Variables Have Uncertainties [duplicate]

Does there exist a method in Mathematica for fitting some function f(x; a, b)=y (with parameters a, b) to data of the form {x, y} when both x and y have different uncertainties? It seems like it would ...
0
votes
1answer
99 views

How to Find minimum and maximum using `FindMaximum[]` and `FindMinimum[]`

this is the data that i use to plot. data_damped_osccilation this is my code so far, however it still give me error ...
0
votes
2answers
63 views
3
votes
2answers
225 views

Is there is a decreasing function that fits my data?

Cross-posted in http://tieba.baidu.com/p/4440556337 http://tieba.baidu.com/p/4440547130 I was wondering if there is a function that fits the following data perfectly or properly. There is a ...
2
votes
1answer
133 views

Standard error of linear fit parameters

I fitted data belonging to a MSD (mean squared displacement of a vibrating micrometer sized particle) by using a linear function: ...
0
votes
1answer
49 views

Failed to extract parameters by fitting data with ODE

I'm trying to extract 4 parameters by fitting one set of data with an ODE via NonlinearModelFit. I originally thought the process should be straightforward, but later on I found I was totally wrong. ...
3
votes
2answers
256 views

Why can't FindFit get the proper result in this problem?

Cross-posted in http://tieba.baidu.com/p/4425634583 The mathematica helps me solve one differential equation in numerial method and got the data of the answer,but the taylor series fit is not good in ...
10
votes
4answers
2k views

How can I compute and plot the 95% confidence bands for a fitted logistic regression model?

I have a set of binary data that I' d like to fit a logistic regression model to and show the 95% confidence band around the fitted function. I can produce the regression model but how do I compute ...
0
votes
1answer
39 views

NonlinearModelFit for analytical data is giving errors [closed]

"x is lambda, y is alpha, z is the factor of pressure" ...
0
votes
0answers
46 views

fit multiple dataset with a single ODE to extract parameters

I found my problem very similar to the one discussed in here. But I'm having difficulties to fit multiple dataset (with varied temperatures) to a single ODE. The hurdle for me now is since the rate ...
0
votes
0answers
83 views

Maximum Likelihood Estimation of Gamma-distribution Scale parameter

I have the following tasks: Generate random sample with given parameters shape = 2, scale = 0.001 and shape = 2, scale = 1/1200 for the right censored sample; Using Maximum Likelihood Method ...
0
votes
1answer
64 views

FindFit only fitting portions of data

I'm currently trying to fit some complicated data sets and I am having some luck. The higher temperature data works just fine with FindFit. Unfortunately, however,...
0
votes
0answers
44 views

Plotting error bars in both dimensions for straight line model [duplicate]

I want to fit a straight line model of the form $y_i = a+ b\ x_i$ to the list of $(x, y)$ pairs given below. How can I plot the data with error bars in both coordinates? ...
2
votes
1answer
88 views

Fitting EV charging curve

I would like to fit my set of data (x = time and y = power) as seen below, and obtain function of x describing it as close as possible, in order to manipulate it (applying different SOC, time offsets ...
13
votes
5answers
2k views

Fit image of mountain to gaussian

I want to detect the edges of an image of a mountain and then fit that to a gaussian. I am unsure about how to only get the mountain edge, rather than every single edge in the image. How do I ...