Talk:Linear model

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 5 September 2018 and 12 December 2018. Further details are available on the course page. Student editor(s): Chenruduan.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 02:37, 17 January 2022 (UTC)

Mergers?

A variety of mergers has been proposed. Please add to the discussion at Talk:Linear regression.

what does that mean??

"The variance is also not restricted to being normal." --145.107.9.241 (talk) 12:13, 21 April 2008 (UTC)

Notation is inconsistent: transpose is indicated sometimes by T, sometimes by '. —Preceding unsigned comment added by 216.195.149.49 (talk) 02:55, 6 July 2008 (UTC)

Suggestion: delete and redirect to "linear regression"

This article is misleading and redundant. It is misleading because, for no apparent reason, it largely consists of a derivation of the ML estimator under normality. But it is a common fallacy that the errors in linear regression must be normal. Although the article does not explicitly state the errors must be normally distributed, the reader could draw that impression. It also contains a number of other problems: it fails to specify what makes the model "linear," it says the assumption X is of full column rank means the "parameters" are not linearly dependent when ought to say "covariates," it claims the errors must have a mean of zero and spherical distributions neither of which is generally required, it claims the X's are fixed (also an unnecessary assumption), and it fails to mention the ML estimator of \sigma^2 is biased. Most of these problems could be fixed, but why? The article is redundant: there's nothing here shouldn't instead be discussed in the articles on least squares, linear least squares, or linear regression (possibly others too: the number of redundant articles on basic regression models is staggering). I suggest deleting this article and redirecting to linear regression. Sked123 (talk) 21:46, 11 August 2008 (UTC)

Good luck explaining your statement there. Please make the distinction between the robustness of the model and the violation of the assumption that σ²(err) = 1, because that's also what I have learned. So apparently something has to be changed in the first sentence too (if we keep the article):

which are uncorrelated random variables each with expected value 0 and variance σ2

Variances tend to be σ², yes... --Selach (talk) 08:10, 25 September 2008 (UTC)

Added section on UMVU estimation (incorporating another article), responding to one-year of the previous complaints

A year passed since the complaints were made that this article only presented ML theory (the ML method wagging the estimation dog, since problems of ML estimation are minimized).

I incorporated the LS estimation material in another subsection, so the article is more useful. The LS estimation of coefficients article isn't easy to find, imho. Kiefer.Wolfowitz (talk) 21:16, 27 June 2009 (UTC)

Merge proposal

(June 2009) There are already too many articles on regression analysis containing too much overlap. More importantly, there needs to be room for an article that outlines all the uses of "linear model" in statistics, as this is not confined to regression. Logically this should go under "linear model", while stuff about specically about regression should go in regression-specific articles. Melcombe (talk) 09:25, 29 June 2009 (UTC)

Agree, this article and the Linear regression are both about the Linear regression model (which for some reason doesn't exist at the moment of writing this comment) and thus should be merged together. Seeing as Linear regression is better structured, let's simply delete Linear model and transfer all useful material to wikipages where it belongs. // Stpasha (talk) 03:03, 1 July 2009 (UTC)

Comment. Perhaps leaving this as a (simple) disambiguation page would be a better result than deleting it. - dcljr (talk) 07:39, 29 December 2015 (UTC)

Clarity in what the function phi is?

Are phi the non-linear (or linear) functions of the independent variables X? ie phi1 is the function (linear or non-linear) of X1? Granzer92 (talk) 14:19, 17 February 2024 (UTC)