Aug 21, 2017 14:49
6 yrs ago
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Russian term
Not a translator
circularity
Russian to English
Science
Environment & Ecology
фитоценология
Слово "circularity" встречается в нескольких фразах в научных статьях, смысл которого в этих фразах я понять не могу. Привожу эти фразы.
The methodological and computational effort the authors undertook to prove bias is impressive, and they address a frequently mentioned concern: the circularity involved in the use of indicator values derived from species lists.
According to both Ellenberg (1974) and Landolt (1977), indicator values cannot be measured in the field, but only compared with field data. Second, Zeleny & Schaffers (2012) address circularity as a source of bias.
They find that 'to confirm the risk of this circularity in real analysis is, however, nearly impossible.
This involves a comparison of three matrices, where one of these (the plot by indicator value matrix) is a matrix product of the other two (plot by species, species by indicator values), a classical case of circularity, preventing statistical inference as proposed by Zeleny & Schaffers (2012).
There has been criticism concerning the inherent circularity and the lack of statistical calibration against measured environmental variables. While the circularity issue has been clarified and a conservative method for evaluating correlations has been devised (Zeleny & Schaffers 2012), the calibration issue has only been solved in an exemplary fashion for subsets of species that are too small to allow wider application (Ertsen et al. 1998). Wamelink et al. (2002) pointed out that mean EIVs should only be compared within broad vegetation types such as phytosociological classes (cf. Wamelink et al. 2003; Witte & von Asmuth 2003).
Заранее благодарю за помощь
The methodological and computational effort the authors undertook to prove bias is impressive, and they address a frequently mentioned concern: the circularity involved in the use of indicator values derived from species lists.
According to both Ellenberg (1974) and Landolt (1977), indicator values cannot be measured in the field, but only compared with field data. Second, Zeleny & Schaffers (2012) address circularity as a source of bias.
They find that 'to confirm the risk of this circularity in real analysis is, however, nearly impossible.
This involves a comparison of three matrices, where one of these (the plot by indicator value matrix) is a matrix product of the other two (plot by species, species by indicator values), a classical case of circularity, preventing statistical inference as proposed by Zeleny & Schaffers (2012).
There has been criticism concerning the inherent circularity and the lack of statistical calibration against measured environmental variables. While the circularity issue has been clarified and a conservative method for evaluating correlations has been devised (Zeleny & Schaffers 2012), the calibration issue has only been solved in an exemplary fashion for subsets of species that are too small to allow wider application (Ertsen et al. 1998). Wamelink et al. (2002) pointed out that mean EIVs should only be compared within broad vegetation types such as phytosociological classes (cf. Wamelink et al. 2003; Witte & von Asmuth 2003).
Заранее благодарю за помощь
Proposed translations
(English)
| 4 +1 | cause and effect argument that takes you back to the cause |
Jack Doughty
|
| 3 | circularity of reasoning |
Frank Szmulowicz, Ph. D.
|
Proposed translations
+1
8 mins
Jack Doughty
United Kingdom
United Kingdom
Native in English
United Kingdom
Translator since 1953
Native in: English
Works in: Russian to English, German to English, English
Related KudoZ points
:
88
cause and effect argument that takes you back to the cause
Definition from MacMillan's Dictionary:
"a situation in which a series of causes and effects leads you back to the original cause, producing an argument that does not mean anything".
Using values derived from lists, not from work in the field, creates such a situation.
"a situation in which a series of causes and effects leads you back to the original cause, producing an argument that does not mean anything".
Using values derived from lists, not from work in the field, creates such a situation.
11 hrs
Frank Szmulowicz, Ph. D.
United States
United States
Native in English
United States
On time, on target, on budget.
Native in: English 
, Polish
Works in: Polish to English, English to Polish, Russian to Polish, and 1 more.
Related KudoZ points
:
32
circularity of reasoning
In a previous study, Zelený & Schaffers (2012) pointed out similar issue with testing the significance of relationship between mean Ellenberg values and scores from ordination diagrams or results of cluster analysis, which was explained by circularity of reasoning.
http://www.davidzeleny.net/doku.php/evs2014
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. Schaffers. Keywords. Bio-indication; Circularity of reasoning;
http://onlinelibrary.wiley.com/doi/10.1111/j.1654-1103.2011....
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or results of cluster analysis, which was explained by circularity of reasoning.
https://www.academia.edu/24363417/Integration_of_European_fo...
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Mean Ellenberg indicator values: too good to be true
Leave a reply
Zeleny-David-EVS-2012 2I started to think more intensively about Ellenberg indicator values issue at one conference while listening to the presentation, where a colleague used mean Ellenberg indicator values as explanatory variables in constrained ordination. I considered this as a kind of statistical heresy, perfect example of circularity of reasoning – you take your vegetation data, calculate mean Ellenberg indicator values for each plot, and in turn use these mean values to explain the original data. But it’s tempting – mean Ellenberg values are often considered as good proxies for measured environmental variables, and they are easy to calculate, so using them as explanatory variables is attractive. I tried that – I took a dataset with measured soil pH and calculated mean Ellenberg values for soil reaction, and compared how much variation in species data will be explained by pH and how much by mean Ellenberg; Ellenberg was a way better predictor than measured pH. Ok, so here we have the consequence of circularity. Thinking it through, I concluded that the reason is that mean Ellenberg values carry legacy of the species composition, from which they were calculated – if two plots have the same species composition, their mean Ellenberg values will be identical (considering mean not weighted by species covers), and if the species composition differ a bit, Ellenberg will change just slightly (changing one or a few numbers while calculating the mean doesn’t change the result too much).
https://davidzeleny.files.wordpress.com/2012/09/zeleny-david...
https://davidzeleny.wordpress.com/2012/09/23/ellenberg-value...
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Note added at 21 hrs (2017-08-22 12:04:39 GMT)
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@vasilev: I thought it useful to find the way the author himself describes circularity. Effectively, it appears to be the case of conclusions being built into the starting data:
use data to calculate mean Ellenberg indicators,
use mean Ellenberg indicators to explain the original data.
In the example below, the relationship between soil PH and species composition is calculated. However, mean Ellenberg indicators are corrupted with species composition and cannot be used as independent variables to infer the effect of soil PH on species composition.
http://www.davidzeleny.net/doku.php/evs2014
cccc
. Schaffers. Keywords. Bio-indication; Circularity of reasoning;
http://onlinelibrary.wiley.com/doi/10.1111/j.1654-1103.2011....
cccccccccccccccccccccccccccccccc
or results of cluster analysis, which was explained by circularity of reasoning.
https://www.academia.edu/24363417/Integration_of_European_fo...
cccccccc
Mean Ellenberg indicator values: too good to be true
Leave a reply
Zeleny-David-EVS-2012 2I started to think more intensively about Ellenberg indicator values issue at one conference while listening to the presentation, where a colleague used mean Ellenberg indicator values as explanatory variables in constrained ordination. I considered this as a kind of statistical heresy, perfect example of circularity of reasoning – you take your vegetation data, calculate mean Ellenberg indicator values for each plot, and in turn use these mean values to explain the original data. But it’s tempting – mean Ellenberg values are often considered as good proxies for measured environmental variables, and they are easy to calculate, so using them as explanatory variables is attractive. I tried that – I took a dataset with measured soil pH and calculated mean Ellenberg values for soil reaction, and compared how much variation in species data will be explained by pH and how much by mean Ellenberg; Ellenberg was a way better predictor than measured pH. Ok, so here we have the consequence of circularity. Thinking it through, I concluded that the reason is that mean Ellenberg values carry legacy of the species composition, from which they were calculated – if two plots have the same species composition, their mean Ellenberg values will be identical (considering mean not weighted by species covers), and if the species composition differ a bit, Ellenberg will change just slightly (changing one or a few numbers while calculating the mean doesn’t change the result too much).
https://davidzeleny.files.wordpress.com/2012/09/zeleny-david...
https://davidzeleny.wordpress.com/2012/09/23/ellenberg-value...
--------------------------------------------------
Note added at 21 hrs (2017-08-22 12:04:39 GMT)
--------------------------------------------------
cccccccccccccccccccc
@vasilev: I thought it useful to find the way the author himself describes circularity. Effectively, it appears to be the case of conclusions being built into the starting data:
use data to calculate mean Ellenberg indicators,
use mean Ellenberg indicators to explain the original data.
In the example below, the relationship between soil PH and species composition is calculated. However, mean Ellenberg indicators are corrupted with species composition and cannot be used as independent variables to infer the effect of soil PH on species composition.
Note from asker:
| Dear Frank MacroJanus, Many thanks for your reply. But I would like to have an unambiguous and definite answer. |
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