# Talk:Two-way analysis of variance

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A lot of this is currently un-editable. Michael Hardy (talk) 06:52, 20 December 2011 (UTC)

It looks like this started as an upload of a scanned statistics class project. While this is two-way ANOVA, the content comes from a very narrow and non-expert context, so there are many missing concepts and connections to other related subjects, like one-way ANOVA. I just edited the article for grammar and consistent usage of terminology, but it really needs a major rewrite. Also, I think because of the title, and the lack of links to other Wiki articles, this article seems to be an orphan or detached, and hard to find. I added links to analysis of variance and one-way ANOVA. Everettr2 (talk) 16:49, 2 May 2012 (UTC)

I cannot figure out how to edit it, but the initial table looks like it should have n=71 for each of the cells instead of n=70.Tsanders2753 (talk) 12:31, 4 May 2012 (UTC)

Good catch, I looked in the original data for the example and it runs from 1922 to 1992, so it is 71 years, and n should definitely be 71. I have changed the figure. Eventually, this should be wikified, but we may want to think about the value of the content first. Starting over is definitely an option I think.Everettr2 (talk) 21:07, 4 May 2012 (UTC)

I think all of the handwritten inequalities for the right hand side of the confidence intervals are written backward. We have "something <= value >= other thing." What we should have is "something <= value <= other thing." These mistakes are in the image files manual4.jpg, manual5.jpg, and manual6.jpg. Everettr2 (talk) 20:05, 7 May 2012 (UTC)

I just looked at the data used for this example of two-way ANOVA, and I think there is a problem there. I think this two-way ANOVA assumes the observations are independent, but from the data, they are obviously not. The samples are the teams in the Word Series of baseball, and the same team appears more than once in the series of samples. Some teams appear much more often than other teams do. This analysis could be more appropriately described as, "Do the Yankees have a home field advantage."  :-) There are forms of ANOVA that can handle this sort of data, but I don't think the contributors of this article were aware of such alternate forms. I am not sure how much not having independent samples affects the outcome of this particular analysis. Can anyone, preferably an ANOVA practitioner, comment? Everettr2 (talk) 16:35, 8 May 2012 (UTC)

I added a link from Analysis of variance to this article. It will be interesting to see if the link will add any additional views detectable in the page view statistics here. Everettr2 (talk) 17:35, 8 May 2012 (UTC)

The handwritten example is very long and provides relatively little insight. I think it should be removed from the page. — Preceding unsigned comment added by Dansbecker (talkcontribs) 17:24, 26 June 2012 (UTC)

I think the whole article as it is written is garbage. It does not say that there are different types of two-way ANOVAs e.g. it is possible to have repeated measures or mixed model ANOVAs, and the author seems to be oblivious to the fact. Furthermore, all the images are first printed and then scanned!?! I am wondering why the author did not just print directly from SPSS into Adobe Acrobat or another printer that preserves the vector format of the output? In any way, I suggest deletion of the whole article except for the introduction, and then better provide links to external web pages, rather than having this badly written stuff. And then wait someone with enough free time and expertise to write a nice article. Otherwise, I don't think anyone would waste his time to repair the garbage work that is currently present Danko Georgiev (talk) 02:21, 26 September 2012 (UTC)