Answered
Finding quantiles from bucket/frequency data
Check this out: x = (1:5)'; freq = [.4 .3 0 .2 .1]'; ecdf(x,'freq',freq) You can provide x values and their freque...

13 years ago | 0

Answered
How to check if data is normally distributed
The functions you mention return H=0 when a test cannot reject the hypothesis of a normal distribution. They can't prove that th...

13 years ago | 0

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Answered
Normal Distributions: Standard Deviation from Statistics Toolbox vs Standard Deviation computed using std(data)?
The expression you show for X defines grid of values over which the fitted pdf is to be calculated for plotting. I don't seen th...

13 years ago | 0

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Defining my own response model using Regstats function
One way to do this is to move all the known stuff to the left-hand-side: y - 3*x1 - 4*x2 - 5*x3 = a*x1^2*x2 + b*x2^2*...

13 years ago | 0

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Answered
How to fit the Copula to the data beased on parametric marginal distribution?
If you have fit the marginals so that you have both the family (such as generalized Pareto) and the parameters, you could use a ...

13 years ago | 0

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Answered
How does multcompare function work?
Can you be more specific about what code you ran? When I try this, I only get groups 1 and 2, comparing the two columns: >>...

13 years ago | 1

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Answered
Group-specific predictors in nlmefit
If you are happy with a toy illustration rather than a realistic example, here's one. Set up some fake data following a linear m...

13 years ago | 3

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Answered
Curve Fitting with Individual trial function
If you are talking about the Curve Fitting Toolbox, try this: f = @(a,b,c,x) a*sqrt(x).*(b*x.^2+exp(c*x)) y = f(1,2,-3...

13 years ago | 0

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Answered
Error when using custom pdf for mle
The mle function needs a real pdf. Yours isn't normalized to integrate to 1. Here's an example that integrates to 1 from 0 to +I...

13 years ago | 0

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why square() cannot work with cftool
I suspect this is because the derivative of the function is always 0 or +/-Inf. The optimizer that tries to perturb the inputs i...

13 years ago | 0

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How to keep a Fixed Effect constant in NLMEFIT and NLMEFITSA?
I can't think of any way to fix the variance. To fix a parameter value, I suppose you could write a new function model=@(PH...

13 years ago | 0

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Testing for a Poisson Process
I find the same thing. I got 52/1000 rejected the first way. That's close to the 5% value that you would expect. I got fewer the...

13 years ago | 0

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Answered
program for calculating skin probability not working. please help.
Best to keep the discussion in a single thread <http://www.mathworks.com/matlabcentral/answers/41974-why-change-in-mean-and-cova...

13 years ago | 0

Answered
Problem in gmdistribution function
See <http://www.mathworks.com/matlabcentral/answers/41974-why-change-in-mean-and-covariance-doesnot-effect-gmdistribution this> ...

13 years ago | 0

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why change in mean and covariance doesnot effect gmdistribution
There are two ways to create a gmdistribution. One is by specifying the mean, covariance, and mixing proportion. The result is a...

13 years ago | 0

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Answered
Differences between treefit() and classregtree() functions in Matlab
There's no difference. The treefit function is older. The classregtree object was intended to do this same thing with a cleaner ...

13 years ago | 0

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Answered
Is that necessary to set the start points for fitting?
Starting points can be very important in some cases. Your analysis is correct. If you fit the 'exp2' model from the cftool GU...

13 years ago | 1

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Answered
Copula family
If you type "help copularnd" or look at the documentation some other way, you'll find these families supported: Gaussian, t, C...

13 years ago | 0

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Answered
Another Issue with Join
Your desired result has v=6 for x=2, but A and B provide different values for v in that case. One thing you could do is joi...

13 years ago | 1

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Answered
Does the Kolmogorov smirnoff test implemented in matlab already perform a correction for small sample sizes?
If you "edit kstest" you'll see some references. The paper by Marsaglia et al. describes how the p-values are computed. The kste...

13 years ago | 0

Answered
'histfit': change line color
h = histfit(randn(100,1)); set(h(1),'facecolor','g'); set(h(2),'color','m') Changing other properties is similar. Just r...

13 years ago | 5

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Answered
Errorbar Plot
Since the points you mentioned appear to be the first two, I wonder if something is setting the axis limits and leaving them fix...

13 years ago | 0

Answered
Obtaining smoother polynomials from polyfit for curve fitting (Best Fit Curve) or an alternate function.
It's hard to say what's going on without seeing your data or results. If you have more than 7 points with distinct x values, the...

13 years ago | 0

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Polyfitting in for loop
Without having your data and just looking at your code, I observe that you have for n = 1 : 1 : 48 ... clippedfP2=cli...

13 years ago | 0

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Answered
Generate random numbers with custom PDF
If you have the Statistics Toolbox, then take a look at the beta distribution. Use it with disttool to see how the parameters af...

13 years ago | 0

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Generating data points according to a distribution
1. If RV is a set of possible data points, you can randomly sample from it. One way to do that if you have the Statistics Toolbo...

13 years ago | 0

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t-test weird degrees of freedom
I can think of two possibilities. First, if you have any NaN values, they are treated as missing and the df would be reduced acc...

13 years ago | 0

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Answered
gscatter grouping variable
The idea is that the jth point on the plot is x=T(j) vs y=C(j) with the symbol chosen according to the group value group(j). The...

13 years ago | 0

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Answered
Naive Bayes - within-class variance must be positive.
Suppose you have data X and classes C. Can you look at var(X(C==1,:) If you see that columns 5, 6, 12, etc. have zero va...

13 years ago | 4

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Answered
expected correlation / transitivity ?
It seems like you are saying [1 c4 c2; c4 1 c3; c2 c3 1] is the correlation matrix of A,A',B'. This is a valid correlation for s...

13 years ago | 0

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