Answered
bimodal Gaussian distribution function
One more try. Check this out: mu=[6;14]; space=[0:.1:20]; x = repmat(space,201,1); y = repmat(space',1,201); L = .5 * (1/(2...

13 years ago | 2

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Answered
What is the order of the regression parameters for a full quadratic model in Matlab?
"help regstats" in my version points to "help x2fx" for the order of terms. The latter confirms that your order is correct, and ...

13 years ago | 0

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Answered
constructing a multilevel regression with random effects
Currently anovan is the only Statistics Toolbox function (aside from a couple aimed at nonlinear fitting) that supports random e...

13 years ago | 0

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bimodal Gaussian distribution function
Is this what you want? F = (1/sqrt(2*pi)) * .5*(exp(-.5*(space-mu(1)).^2) + exp(-.5*(space-mu(2)).^2)); plot(space,F)

13 years ago | 0

Answered
How to fit the best line
Would it be reasonable to compare norm(a-c) with norm(b-c)?

13 years ago | 0

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Answered
Differentiating a cumulative distribution function
You just need to fix your parentheses. Change this int(exp(-(x-mu)^2)./(2.*(sigma^2)) to this int(exp(-(1/2)*((x-mu...

13 years ago | 0

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fitdist - How does it work?
The fitdist function uses maximum likelihood. The exceptions are the normal and lognormal distributions. For the normal distribu...

13 years ago | 2

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Answered
How to create a Coefficent table for regression analysis
What error message? You didn't define the variable stats in the code you provided, so I could imagine that might be a problem. ...

13 years ago | 0

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Answered
What is the algorithm to estimate model coefficients in a Central Composite Rotatable Design?
You could use backlash if you first form an array A of the constant, linear, interaction, and squared terms. Then compute A\Y. ...

13 years ago | 0

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Answered
How to use mhsample or slicesample with ksdensity?
Suppose you have data "mydata" and you want to base the ksdensity on that: mydata = [randn(100,1); 6+randn(150,1)]; a1 =...

13 years ago | 0

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Differentiating a cumulative distribution function
The Statistics Toolbox functions normpdf and normcdf don't accept symbolic inputs. You might be able to use functions like erf, ...

13 years ago | 0

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Answered
Non-linear piecewise fit using fittype() and fit().
How about replacing (x/R)^2 by min(1,(x/R)^2)

13 years ago | 0

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Answered
Exponential random generator broken
Works for me. Try which exprnd dbtype exprnd 1

13 years ago | 0

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How to obtain Nakagami random variable from CDF plot?
The inv function computes a matrix inverse. If you want to invert the function using the Symbolic Toolbox, something like this m...

13 years ago | 0

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Answered
Confidence interval using binofit
The binofit function computes confidence intervals using the Clopper-Pearson method. I believe what you're seeing is because ...

13 years ago | 1

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Answered
which point corresponds to which cluster in kemans function
If you are using kmeans from the Statistics Toolbox, it sounds like the first output is what you want: >> [a,b] = kmeans([0...

13 years ago | 0

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How to use fittype and fit to get a logarithmic fit to some data
If you want to fit y as a linear function of log(x), you can just apply linear methods. For example, here's how to use backslash...

13 years ago | 0

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Surface fitting tool. What does center and scale do?
If you have the Statistics Toolbox, the following commands will reproduce the sftool results: [X,Y,Z] = peaks; x2fx([X(:...

13 years ago | 3

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Answered
Undefined function 'mtimes' for input arguments of type 'nominal'.
Try putting a break in the crossfun function and using "whos" to see what the y value is. If it's a nominal variable, then it lo...

13 years ago | 0

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Answered
Question on error variance in multiple linear regression
The fourth element of the temp output is an estimate of the variance of the residuals. This depends on the noise rather than the...

13 years ago | 0

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Model fitting and hypothesis testing
The GeneralizedLinearModel interface is intended to be a step forward over glmfit, though the latter is still there. The new ver...

13 years ago | 1

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Answered
How can I compute the Multivariate normal cumulative distribution from vector a to vector b?
Try "help mvncdf" again and read down to the syntax Y = mvncdf(XL,XU,MU,SIGMA) This sounds like what you want.

13 years ago | 2

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Answered
How does matlab cftool (curve fitting toolbox) determine StartPoint for Sum of Sin fit?
It's not that proprietary. It's implemented in MATLAB code that's shipped with the product, in particular in the @fittype/privat...

13 years ago | 1

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Answered
Repeated measures ANOVA in built-in function?
There's not a repeated measures anova function in the Statistics Toolbox. You may find something on the File Exchange. There ...

13 years ago | 1

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how to fit a curve by splitting it into linear region and quadratic region?
Maybe you can get somewhere by trying this and imitating it: x = linspace(0,10)'; y = 2 + x - (x-5).*(x>5) - (x-5).^2.*(...

13 years ago | 1

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I would like to be able to export fit residual values. Is this possible? If so how?
That's hard to read (consider formatting it as code), but it appears to create a variable named "residual" in the workspace. Is ...

13 years ago | 0

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fitting implicit functions with NLINFIT
NLINFIT wants a response vector Y and a function with unknown parameters. You could try supplying the response vector Y = z...

13 years ago | 0

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Answered
Fitting Histogram Data to a Normal Distribution - How to incorporate chi-sq?
The normfit function estimates mu and sigma from the raw data. It's possible to estimate mu and sigma from the histogram bin ...

13 years ago | 0

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Least-squares method in normfit with censoring?
If I test a bunch of lightbulbs for a month and see how long they last, maybe half of them will burn out and I will be able to o...

13 years ago | 0

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How to use CurveFitting coefficients in the rest of the code?
Although I don't understand what coeffvalues(f) doesn't work, nor why f(t2) doesn't work, nor where the a1 error message comes f...

13 years ago | 1