factoran() vs EM Algorithm FA = fa() : Understanding the difference on carbig.mat in ...toolbox​\stats\sta​tsdemos

2 次查看（过去 30 天）
Isma
Isma 2015-7-23
编辑： Isma 2015-7-25
Hi,
Could someone explain me the difference between Matlab built-in
factoran(x,k)
vs user-defined
EM algorithm fa(x,k)
-------------------------------?? ( code )
load carbig;
X = [Acceleration Displacement Horsepower MPG Weight];
X = X(all(~isnan(X),2),:);
lambda= factoran(X, 2)
and
lambda2=fa(X,2) % from <http://www.mathworks.com/matlabcentral/fileexchange/28906-factor-analysis>
Specically I'd like to know why
factoran
outputs a (5*2) matrix of loadings with
size(X,1) = 120
whereas:
EM algorithm fa
outputs a (120*2) matrix of loadings matching my expectations, to the extent that for each data/variable i end up with a sensitivity of the factors.
Best,

请先登录，再回答此问题。

采纳的回答

Tom Lane
Tom Lane 2015-7-24
It sounds like you want the fifth output of factoran rather than the first.
  1 个评论
Isma
Isma 2015-7-25
编辑：Isma 2015-7-25
That's what i've realized ex-post . it sounds like the EM algo outputs the factor 'scores' (not the factor loadings), matching more or less the 5th output of factoran. cheers.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Get Started with Statistics and Machine Learning Toolbox 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by