406 reputation
210
bio website
location Rome, Italy
age 26
visits member for 1 year, 6 months
seen Jul 30 at 16:36

Jul
2
awarded  Curious
Mar
2
awarded  Popular Question
Feb
19
awarded  Yearling
Jun
25
comment Why FrontEnd`KernelExecute doesn't work in KeyEventTranslations.tr?
I don't really understand what you are trying to say, nor what kind of problem you encountered. Have you gained better understanding of these commands in last days? If there is something still unclear, consider posting a new question.
Jun
25
comment Interpolating function as a model in Mathematica's procedures for fitting
That's exactly what I did :) Still, I miss such a feature integrated in Mathematica.
Jun
16
asked Interpolating function as a model in Mathematica's procedures for fitting
May
22
awarded  Necromancer
Apr
19
comment Copy last/second last (etc.) input from history into current cell
Have you seen edit to my answer? I am interested if it works with somebody else, because I didn't test it much.
Apr
19
comment Is it possible to marginalize one or several parameters obtained from fitting procedure?
Here is explained how one can plot confidence region from any covariance matrix c. Now I am trying to figure out how to get standard equation of ellipsoid from {x, y, z}.ci.{x, y, z} == t, where ci is the inverse of c. This would help in analytical analysis and make the plotting easier and prettier. Position of ellipsoid is given from Eigenvectors[c], but I am still missing radii. Different confidence level would influence the size of ellipsoid by scale factor Sqrt@InverseCDF[ChiSquareDistribution[n], confidenceLevel].
Apr
19
comment How to use a 3×3 covariance matrix to plot an error ellipsoid?
hahaha No, no, sorry, that's not what I wanted to say! I was more explicit to drag attention, only because comments are not often read. Honestly, I myself learned a lot from this answer and it is actually the answers for my question, too! (which is why I called it brilliant, as it is for any dimension). And now: if you are not interested in one variable and you want to see confidence regions for the rest of variables, you can either put some fixed value to that one variable and get new correlation matrix (by fitting again), or integrate probability function over that variable, eg. marginalize.
Apr
19
comment How to use a 3×3 covariance matrix to plot an error ellipsoid?
Certainly, whuber. The comment was not for you, but for beginners who have that common mistake in interpretation. As the OP didn't really know all parts of procedure when he posted the question, he also couldn't specify exactly what he needed. The comment for you, whuber, would be to give interpretation on what you are doing as you are the one who has the knowledge :) And therefore, avoid wrong interpretations by beginners.
Apr
19
comment How to use a 3×3 covariance matrix to plot an error ellipsoid?
If you are interested in only two variables you should not slice the ellipsoid!! Wrong! You have to do marginalization, which is in this case even simpler. Like I explained here you have to modify the covariance matrix and perform this brilliant procedure again for reduced number of variables.
Apr
17
asked Is it possible to marginalize one or several parameters obtained from fitting procedure?
Apr
17
awarded  Critic
Apr
17
comment How to get confidence bands of parameters from a fitting procedure?
Yes, I'm thinking of it, too. But would that be the right thing to do, I mean statistically?
Apr
17
comment How to get confidence bands of parameters from a fitting procedure?
This is very nice, thank you! However, I am facing with a new problem now. I have three parameters, but I am interested in only two of them. How to get an ellipse from the ellipsoid? I'm not even sure (mathematically) should one integrate over the third variable or project the ellipsoid on a plane. Either way I am not sure how to calculate it... Do you have some advice?
Apr
17
accepted How to get confidence bands of parameters from a fitting procedure?
Apr
17
comment How to get confidence bands of parameters from a fitting procedure?
Yes, that is exactly what I need! It is listed in the options, but I can't find examples. I don't understand how to use the output of nlm["ParameterConfidenceRegion"]
Apr
17
asked How to get confidence bands of parameters from a fitting procedure?
Apr
14
comment How to select and delete all Output cells?
How about including Undo option? Instead of NotebookDelete[..] use MathLink`CallFrontEnd[FrontEnd`SelectionAddCellTags[nb, {"$deleted"}]] and then just before the last command SelectionMove[..] insert this If[NotebookFind[nb, "$deleted", All, CellTags, AutoScroll -> False] =!= $Failed, MathLink`CallFrontEnd[FrontEnd`SelectionRemoveCellTags[nb, {"$deleted"}]]; FrontEndTokenExecute["Clear"]];