MATLAB is a high-level language and interactive programming environment developed by MathWorks. It is the foundation for a number of other tools related to statistical analysis, including Statistics Toolbox, Optimization Toolbox, Curve Fitting Toolbox and Neural Network Toolbox.

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19 views

Neural networks creates negative output

I am using a simple feedforward neural network in MATLAB to predict the output for inputs in the range [1e-5, 0.3]. (These are the activations of another network.) I am using a sigmoid function for ...
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0answers
7 views

How to check if data needs to be seasonally differenced in MATLAB

I am forecasting data using ARIMA. I would like to know if there is any test to check if seasonal differencing is needed in the ARIMA model. I know R uses Canova Hansen test, but does MATLAB provide ...
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36 views

Trend: Linear or exponential

I am trying to forecast data using ARIMA. I have read articles which say that I should first take the log of the series, if my series follows an exponential trend. My question is: Is there a ...
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1answer
19 views

DBSCAN & OPTICS [on hold]

I'm looking for DBSCAN and OPTICS matlab codes for clustering 'm' pattern in 3D space: the imput is a matrix where the 'm' rows are vectors a the 'n'=3 columns are X,Y,Z axes. I would also like the ...
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0answers
13 views

Intuition behind which eigenvectors to use in PCA for orthogonal regression

I am learning PCA, and while this seems like an obvious question, I can't seem to understand some of the ideas behind which eigenvectors to use when performing orthogonal regression with PCA. My code ...
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2answers
62 views

Unimodal or bimodal data (MATLAB)?

I am trying to figure out what I did wrong or what I could do to get accurate results. I have n vectors of data, and I am trying to decide whether each dataset is unimodal or bimodal. I assumed that ...
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1answer
10 views

Simulating Gaussian Mixture signals

I am trying to simulate a signal produced from a GMM of 3 mixtures. Here's MATLAB code ...
0
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1answer
25 views

Radial distribution to cartesian coordinates

I'm trying to go from a radial distribution in polar coordinates to cartesian coordinates. I'm using Matlab and have tried pol2cart, but are having some trouble getting a matrix with probabilities. ...
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1answer
30 views

Is it posible to perform the inverse of multidimensional scaling analysis

We have lot of 3D data and we reduced it to 2D for performing fuzzy clustering and obtaining prototypes. We used some matlab functions that were very well documented. Now we would like to see to which ...
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0answers
12 views

how to plot wind rose in matlab [migrated]

I have generated a wind rose in Matlab using this link's coding. enter link description here Its in colors, I want No colors in my Wind Rose, how do I proceed? below is my code which handles the ...
2
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1answer
27 views

Get fitted values estimated in ARIMA in Matlab

I am using Matlab to forecast time series data using ARIMA algorithm. I am able to get forecasted values, but unable to get the fitted values. This is what I mean. In R: ...
2
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1answer
56 views

R square test in matlab

I did the code for my $R^{2}$ (R square) test in MATLAB but it is not working accordingly. I want to test the Weibull distribution against my raw data, hence I want to do an $R^{2}$ (R square) test. ...
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1answer
24 views

How to implement a 2-D Gaussian Processes Regression through GPML (MATLAB)?

I just touched Gaussian processes two weeks ago. I am not very familiar with the selection of a model and its hyperparameters. Here is the demo code that I run for a 2-D Gaussian processes regression. ...
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1answer
44 views

Nonparametric ANOVA with interaction?

Is there any nonparametric version of ANOVA able to deal with multiple factors AND evaluate their interaction(s)? If the interactions are really impossible to evaluate, is there any generalization of ...
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2answers
56 views

Testing goodness of fit

I am using MATLAB 2012a to run 3 tests. With my data, I obtain very small values, and for the Anderson–Darling (A–D) tests, the results are not even normalized. Please verify my code. I am also using ...
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0answers
22 views

How to implement data I have to svmtrain() function in MATLAB?

I have to write a script using MATLAB which will classify my data. My data consists of 1051 web pages (rows) and 11000+ words (columns). The first 230 rows are about computer science course (to be ...
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0answers
18 views

Goodness of fit for orthogonal least square regression

We have a set of XY coordinates which we have fitted with an orthogonal least square regression model. We have a vector of residuals for each point and the fitted line. How do we assess goodness of ...
5
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1answer
49 views

Zero inflated negative binomial with selection

I am looking for a Stata (or R/Matlab if there's no Stata) implementation of the model described by Greene (1994) (http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1293115). It is essentially a ...
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0answers
15 views

Understanding matlab code for converting raw input images into matlab format

f = fopen('train-images-idx3-ubyte','r'); [a,count] = fread(f,4,'int32'); g = fopen('train-labels-idx1-ubyte','r'); [l,count] = fread(g,2,'int32'); fprintf(1,'Starting to convert Training MNIST ...
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2answers
35 views

Is a restricted Boltzmann machine trained using a contrastive divergence algorithm an unsupervised learning method?

I am designing RBM with CD training methodology in MATLAB. CD is an unsupervised learning algorithm, so I do not need to use any label information included in input. Does that make sense?
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1answer
55 views

factor analysis for given data with help of matlab

suppose that we have following data i have done covariance matrix and eigenvalue decomposition ...
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0answers
17 views

HMM library, different length sequences training

I'm using the Kevin Murphy's HMM library in MATLAB(http://www.cs.ubc.ca/~murphyk/Software/HMM/hmm.html) There is a section called 'How to use the toolbox'. There is this example for GMM ouputs: ...
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0answers
54 views

Fitting for a Poisson-Gaussian Mixture Distribution

First of all, I am rather new to statistics, so go easy on me. I am aware that the negative binomial distribution can be thought to arise as a result of letting the $\lambda$ parameter in a Poisson ...
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1answer
40 views

Calculate principal components

Given the following data: ...
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0answers
23 views

Multivariate Multiple Regression with Repeated Dependent Measures [MATLAB]

[Originally posted in Mathematics before I realized this was a better venue] I have a dataset with $p$ predictors for $i$ items (so multiple regression). For each of $s$ subjects, I have $r$ repeated ...
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1answer
42 views

structural breaks in time series using matlab

in a plot of my time series there is clearly visible that there is structural break, but I have to find the exact date. I want test this with the chow test. Although I understand how to perform this ...
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23 views

clarification Johansen cointegration matlab

To my understanding the Johansen cointegration test, will test first if the time series have zero cointegrations, if rejected, the Johansen test will test for one cointegration, if rejected, it will ...
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0answers
25 views

Implementation for Co-Clustering

I am looking for existing implementations for co-clustering (aka biclustering). I came up with biclust function available in MATLAB, but still I am wondering if ...
1
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1answer
36 views

How do I compute the density of this distribution

Ferdosi et al define six artificial datasets to test density estimation methods. Part of the fourth dataset is defined as: $$ Uniform(x,y) = [0,100], Gaussian(z) = [M = 50, var = 5] $$ Where $M$ is ...
2
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0answers
46 views

Why is least squares performing as well as ridge regression when there is multicollinearity?

I am learning about ridge regression, so I am implementing it in MATLAB as practice. However, I am having trouble finding a structure of data where ridge regression performs better than an ordinary ...
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0answers
22 views

How can i perform Cosinor analysis in Matlab?

I have monthly and daily data from births in Greece and i want to to do a cosinor analysis to find the rhythm, (circadian,circannual,half yearly etc etc ) How can i use Matlab to perform the cosinor ...
2
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1answer
62 views

Plot two-dimensional Gaussian density function in MATLAB

I am learning ML. I have encountered a lot probability density functions. I want to use MATLAB to illustrate them. For example,the density function of the Normal distribution function in two ...
0
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0answers
29 views

Identifiability for time invariant state space models

Kevin Murphy's Kalman Filter toolbox (for Matlab) contains an example where it's the fact that the state space system in not identifiable causes problems. I include the example in it's entirety but ...
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0answers
23 views

Is there a Matlab code for the probit random effects model for panel data?

Is there a Matlab code for the probit random effects model for panel data? I observe there are Stata codes(a couple of versions) available but I cannot not find any Matlab codes. I would really ...
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0answers
12 views

Implementation of semi parametric methods

Has anyone worked with semi parametric methods to estimate parameters with binary outcome? Examples are like Cosslett (1983) or Ichimura or Klein-Spady. In other words we are looking for semi ...
0
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1answer
39 views

A way to use GPU hardware in matlab [closed]

I know that theano is a python library for using gpu hardware and make effective implementations. Is there any such library or a way to do the same in matlab?
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0answers
6 views

Comparing to vectors of labels that contain different labels, but the same number, and the same places

Problem: After doing two cluster analysis, I get two arrays $V_1$ and $V_2$ of length $N$. I have a groundtruth vector as well $GT$. I want to make the comparison, which is label invariant. Say first ...
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0answers
16 views

How to use posterior function within Matlab

I would like to create a GMM within Matlab and then input an observation x to get the probability of this x. I know the equation is the following: $$p(x) = \sum_{k}p(C_{k})p(x|C_{k})$$ I would like ...
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0answers
14 views

SPM for spatial analysis

Do you know of any study where researchers have used Statistical Parametric Mapping for spatial data only? I found a lot of studies that used it for time-series analysis, but does this analysis work ...
0
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0answers
65 views

How to optimise multi-layer neural network architecture using the genetic algorithm in MATLAB

Can someone please provide me with a summary of how to optimise multi-layer feedforward neural network architecture using the genetic algorithm? I've read a few papers that say this is an effective ...
0
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1answer
47 views

lsqnonneg – variation between results in R and MATLAB

We are trying to do nonlinear least squares fitting in R. We have reference code in MATLAB as below. ...
0
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1answer
28 views

libLinear matlab impementation returns abnormal results

Well hello, this is my first question in CrossValidated. I hope I am in the right place. I am trying to make libLinear work. I am using the interface of matlab but it does not functions normally. To ...
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0answers
44 views

Can you use the chi-squared test with tables of real numbers?

Consider a $N \times 2$ matrix (MATLAB notation): M = [1.2, 3; 1.4, 2; 1.8, 1; 2.0, 2]; That is a $4 \times 2$ matrix where the first column ...
1
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1answer
50 views

Forecasting temperature using CurveFitting

I am assigned with a academic task to forecast temperature using CurveFitting. Please suggest me whether I use Linear regression/ Non-Linear regression or extrapolation? I have to forecast 1 next ...
0
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1answer
20 views

Accounting for groups in GzLM Poisson regression

I am currently trying to perform a regression on data with one predictor and one covariate. The hypothesis I am trying to test is whether the incidence of pores (a hole through a cell) increases when ...
0
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0answers
34 views

Minimum Number of Variables for Effective use of the Genetic Algorithm

From my understanding of the genetic algorithm the population consists of individuals, where each individual is a potential solution made up of "genes", and each gene is a variable. So for a cost ...
0
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1answer
77 views

Explanation of the Regression Plot in the Matlab Neural Network Toolbox

What does the Regression Plot in the Matlab Neural Network Toolbox show? I thought I understood it when I looked at a univariate regression plot, but I've just plotted one for multivariate regression, ...
0
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0answers
23 views

Fitting Noisy Data [closed]

I've written the following code to fit $$f=a*sin(b*x+c)$$ for x=linspace(0,4*pi,100). I know the form of the required function so I can use ...
0
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0answers
21 views

confidence interval for co-variance

is there a way to compute the confidence interval of a co-variance matrix in Matlab.. Suppose I have 2 vectors of stock returns. If I compute a co-variance matrix (2x2) the sample co-variance will not ...
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0answers
28 views

How to find an optimal threshold

Is there a way to find an optimal threshold? I am using MATLAB for this project. I have 2 groups of triangles (distances and angles). I need to find the similarities between two triangles in each ...