Talk:Vertical–horizontal illusion

Different effect at play, easily disproven
The example shows the vertical line effectively dividing horizontal space in two, so it's not entirely "fair". If, instead, the horizontal line starts at the middle of the vertical line (i.e., if the figure is rotated 90 degrees), then the horizontal line appears bigger (try it). If the lines cross at the middle (a '+' sign) or meet at the tip (an 'L'), they appear (correctly) to be the same size.

This suggests the effect is caused by the relative positioning of the lines, not their direction, and makes all subsequent conjectures pointless.

Also, the claim that "rural people are less susceptible" goes against the claim that "people living in open landscapes are more susceptible", since rural people are precisely the ones living in open landscapes.

The whole article appears to make very little sense.

RMN (talk) 18:29, 1 April 2010 (UTC)


 * Thanks for pointing out the (quasi-)contradictory statement [rural does not necessarily indicate living in open spaces, e.g. a jungle village]. It seems the source was pretty hard to read correctly (which is why I misread it previously). I have corrected the article. I would like to see what you mean with your first statement, though. Could you show me (upload) a picture of it? --JorisvS (talk) 19:53, 1 April 2010 (UTC)

Appropriateness of image
The image in the article is terrible as an example. The vertical line is actually longer than the horizontal one, since the ruler in the image only begins measuring on the top of the horizontal line and ignores the width of the horizontal line. Additionally, the effect is accentuated by the bisection -- even the reference points this out -- and if you rotate the image 90 degrees, you'll likely think that the now horizontal line is the longer one (though not as much longer as it was before you rotated it, given that the vertical-horizontal illusion is actually in effect!)   Mike   Blackney  10:24, 30 May 2011 (UTC)
 * Actually, on my screen the vertical line is the shorter one! --JorisvS (talk) 11:37, 30 May 2011 (UTC)

I measured The image on my screen with a ruler, and the vertical and horizontal rulers are of different sizes! While each centimeter of the horizontal ruler is really one centimeter, the 10 centimeters of the vertical ruler are 9,5 cm! Perhaps the pixel ratio of my screen is wrong? And I agree to what Mike Blackney said. The ruler positioning is also wrong, ignoring the width of the lines. Frlara (talk) 23:32, 4 July 2012 (UTC)

Class Project
I, along with a group of students from the University of St. Thomas will be adding to the vertical-horizontal page. We look to add more empirical facts and sources from studies conducted on this illusion. In addition, we will note gender differences as well as why there are cross cultural differences in the susceptibility to the illusion. Demi god is cool (talk) 21:22, 5 October 2011 (UTC)

Prof Comments
Great start revising this page. Intro: Western people show more susceptibility than whom? I don't understand the oblique effect. Provide a reference that the inverted T has the highest magnitude. Development: Some grammar errors in this section with subject/verb and subject/pronoun agreement. Hemispheric neglect: this section needs citation, links, and more explanation. Gender: Hemispheric differences are a form of brain differences. Also your sentence implies that gender differences are only biological (rather than due to social learning differences). This is a major problem. ProfRox (talk) 13:09, 28 November 2011 (UTC)

Student Comments
Clarify the first paragraph of the page. The third sentence in the introduction was confusing (overestimate and underestimate?) relative to the first which only says over estimate. DMB2011 (talk) 20:09, 28 November 2011 (UTC)

-I thought you're Wikipedia page had a lot of good information and it was pretty easy to follow! I do have a few suggestions on the wording though; when you stated "Cross-cultural differences in susceptibility to the vertical–horizontal illusion have been noted, with Western people showing more susceptibility. You could change this to, it has been proven that Western cultures show more susceptibility to..." Also the 'Development' section is a little confusing, maybe start off the paragraph with who the experiment was completed by? Also, perhaps you could add some images of the three different types of vertical–horizontal illusions. Perhaps make a few adjustments and you'll be good to go!

Ama6313 (talk) 23:12, 28 November 2011 (UTC)

You did a good job overall in explaining the illusion. One thing I would definitely do is explain what hemispheric neglect is. Even after reading the paragraph, I have no clue what that means. Other than that I would maybe try to explain why the inverted T configuration produces the highest illusion magnitude. You could also explain why children who show greater personal independence and verbal articulation were more effective in ability to gauge the illusion. I am interested in knowing the mechanisms behind that finding. Nice job though! Shan1603 (talk) 03:12, 30 November 2011 (UTC)

I feel like your article was well laid out, and was overall very well done. I especially liked to see that you included a section on functions for the illusion, makes the information of your article seem very applicable and relevant. Just a couple of things: you could probably link to hemineglect. I checked and there's a wikipage already there for that; either that or maybe you could explain that phenomenon more clearly...or maybe both link it and explain it further. Is there explanation behind why more independent children are better able to gauge the lengths of the lines in the illusion? Also could you be more clear as to what "de-center their attention in a visual display" means (from that same development section; I feel a little unclear about what that means. That's all the feedback I have for you, nicely done. Will4544 (talk) 04:23, 3 December 2011 (UTC)will4544

Good page! It has a lot of information on the topic and is explained very well. It is also not too overwhelming, which is a plus. Nice work! Metz8688 (talk) 15:08, 4 December 2011 (UTC)

Good, clean article. The functional application section is a little confusing. First, the horizontal-vertical illusion as I understand it, is a two-dimensional illusion. If it applies to stepping up stairs (which involves a third dimension), the explanation could be clearer on how the idea translates to real-world application. The first sentence could be omitted, just starting with the following, or another topical sentence broadly explaining the illusion's generalizability/ external-validity. An overview sentence of its relevance also could be in the intro. Overall the article is informative! Wikimister (talk) 00:49, 6 December 2011 (UTC)