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Archive 1

Some added stuff

Added some stuff about its relation to business's, not sure if youll like it!--lincs_geezer 04:23, 6 December 2005 (UTC)--lincs_geezer 04:23, 6 December 2005 (UTC)

Complicating

Wikipedia sometimes baffles me. I write a perfectly straightforward section, and then someone comes along and rewords it to mean exactly the same thing but practically imcomprehensible to the passer by. Simple facts and theories should be left understandable to everyone in my opinion....--lincs_geezer 00:40, 16 September 2006 (UTC)

What-if analysis

"what-if" analysis???? I have never heard anyone actually use this terminology and it should just be deleted, I am a statistical consultant. peace — Preceding unsigned comment added by 131.247.60.178 (talkcontribs) 12 October 2006 (UTC)

'What if' analysis is a subset of the Sensitivity analysis. Sensitivity analysis is done using a number of what if analysis. To clear this further, let us take an event that is affected by two parameters. 'What-if' parameter A is altered? What is the effect on the output? this forms the 'what if' analysis. When n number of such analysis is performed and based on them a uniform causal formula or relationship is aimed at, then that becomes the senstivity analysis. Both are needed. Whereas what if is single incident, senstivity is based on multiple such incidents. — Preceding unsigned comment added by Rshanthakumar (talkcontribs) 27 October 2006 (UTC)

Within microbiological risk asessment there is some debate over whether sensitivity analysis and "what-if" analysis (perhaps more elegantly termed scenario analysis) are two separate things - the aim is perhaps narrowly defined for scenario analysis (what is the effect of changing the values of an input by so much on the output?) - but in the end a very simple scenario analysis (e.g. manually changing the value of your model parameters) seems to me a very similar process to a very simple sensitivity analysis (as alluded to above). In my opinion a passing comment that "what-if?" scenarios can be investigated using sensitivity analysis methods would be all that is necessary. — Preceding unsigned comment added by 62.25.109.195 (talkcontribs) 4 December 2006 (UTC)

Too wordy for mere mortals

The underlying problem i see with this page is that anyone who understands what:

"However, when the assumptions are uncertain, and/or there are alternative sets of assumptions to chose from, the inference will also be also uncertain. Investigating the uncertainty in the inference (regardless of its source) goes under the name of Uncertainty analysis."

means, without having to go through it veeeeery slowly, probably already knows all about sensitivity analysis, and has no use for this page anyway. I personally do not, and have absolutely no idea what anything says. I think that maybe something a little less wordy would be more appropriate for a site such as wikipedia, with the whole 'available to everyone' thing going on.

Splooj (talk) 12:29, 2 April 2008 (UTC)

Good point! I tried to improve by quoting from Leamer and Kennedy, two econometricians I like.

Saltean (talk) 12:37, 18 August 2008 (UTC)

Problems with OAT section

I don't understand the OAT section figures and discussion. How do I get to x=0.5 and y=0.5 by changing only one factor at a time? And if I can get to the point [0.5,0.5] then what prevents me from getting to [1,1]? At a minimum, this section needs a reference.

-- Skeptdc (talk) 10:47, 17 May 2009 (UTC)

Indeed. Why a hypersphere, our of every inscribed shape that could encompass the points? Why not a cube, a simplex, a star, an arbitrary manifold...?
--Livingthingdan (talk) 01:51, 21 April 2011 (UTC)

Skeptdc is right; with OAT in two dimensions one neither gets to [0.5,0.5], nor to [1,1], but only to points [0,0], [0,1] and [1,0] (I have assumed here the origin of the coordinates in the centre of the square/cube/hypercube). The argument is that all OAT point are at most at a distance=1 from the origin by design. Given that the diagonal of the hypecube is in dimensions, if the points are distributed randomly there will be points (in the corner) which are distant from the origin . Hence the paradox of OAT is that all points are in a circumscribed volume near to the origin. This volume becomes negligible with respect to the total volume as increases. Think of the corners: in ten dimensions there are of them.

Another argument against my formulation of the OAT paradox -- which is perhaps implicit in the remark of Skeptdc -- is that when one throws a handful of point in a multidimensional space these points will be sparce, and in no way the space will be fully explored. A retort to this remark is that with OAT one already knows that by design none of the points will be even by chance close to the bounday of the region of interest. In the end, even if one has only a handful of points at his/her disposal, there is no reason why one should concentrate all these points close to the origin.

-- Andrea Saltelli 15:27, 29 June 2009 (UTC)


Thanks for the response, Andrea.

I feel that some more clarification is in order in order to make this make clear to the punters, however.

Consider this remark here: > with OAT in two dimensions one neither gets to [0.5,0.5], nor to [1,1], but only to points [0,0], [0,1] and [1,0]

So, from the initial discussion of the OAT business, I understood that the key factor in the OAT technique is that we change only one parameter at a time, not that the change is in increments of 1 *and* that it is only to one parameter at a time. (I gather that 1 is in fact scaled to me the maximal parameter range. Or are you referring to the ranges over which the parameter can be scaled? In which case, we should perhaps be referring not to "points" by the "intervals".

>The argument is that all OAT point are at most at a distance=1 from the origin by design. Hm - the implication so far sounds like it's stronger than that - it is that the points are constrained to the volume of the, er "hypercross" (?) define as the k-dimensional shape containing all points lying on a vector with all components apart from at most one being zero. If that is so, than the volume which we explore is not a hypersphere at all, and the volume calculations are extraneous - since the shape we explore has a volume of zero for all k.

The first point i suspect that might be a pure talk-page confusion, although i mention it to be sure.

The second one I am sure is an unresolved confusion important. Can two or more parameters be varied simultaneously at any point in the OAT process? If so, how do we know that they remain within the unit hypersphere? Do we have any citations to this point?

--Livingthingdan (talk) 06:11, 11 October 2010 (UTC)

The "OAT paradox" may or may not reflect consensus within the discipline. Either way, this section does not give a coherent explanation of it. Moreover, it is only supported by one citation which appears to belong to the author of that section. This may indicate that this section is original research, or that it needs a rewrite. tagging accordingly. --Livingthingdan (talk) 01:51, 21 April 2011 (UTC)


Hello, We have considerably simplified the discussion about the OAT by: 1. removing the unclear figure about the sphere and the cube; 2. discarding the figure showing the ratio between the sphere and cube volume and the associated discussion.

We have stressed the two major pitfalls of OAT which does not explore enough the input space and does not take into acocunt their simultaneous variation (no possibility to highlight interactions).

We hope that this helps clarifying the matter. Thank you for your comments.

Paola Annoni and Stefano Tarantola

15 March 2012

— Preceding unsigned comment added by Tarantolastefano (talkcontribs) 14 March 2012 (UTC)

Courses and Conferences on Sensitivity Analysis

10:26, 26 November 2009 (UTC)draft stefano —Preceding unsigned comment added by 139.191.246.63 (talk)

Undefined acronym

NPV at the end of the first paragraph is undefined. —Preceding unsigned comment added by 139.229.33.6 (talk) 18:46, 10 May 2011 (UTC)

Proposal for significant changes to this page - please read

Note: these changes have now been implemented.

I would like to propose some fairly significant changes to the structure of this page. I think the comments on this talk page reflect the fact that at the moment, the page is quite poorly organised. Currently, some information appears out of place, duplicated, and in many cases absent. Particularly the methodology section must appear to be extremely confusing to the uninitiated reader, being a list of overlapping classes of methods with no explanation of when or why a practitioner might use each one. Following that, there are several sub-sections with no apparent logical order to them.

I propose to re-organise the page to follow a more logical order, such that the reader is presented with a concise overview, followed by a definitive list of current methodologies, with links to methods. Probably the most widely-accepted technique for global sensitivity analysis, Sobol's method based on variance decompostion, is only afforded two sentences here, which is a shame since most modern sensitivity analyses make extensive use of these techniques. I propose therefore to create a separate page outlining these methods in detail, which can be linked to from this page. I would also add more on the use of emulators and HDMR representations (either on this page or a separate one), since these methods are increasingly in demand.

I would like to stress however that I do not propose to alter the text of the page significantly; rather to re-shuffle it into a more logical order. The page already contains a wealth of collective knowledge, but could definitely be presented better in my opinion.

In summary, some key changes that I propose are the following:

  1. Re-organise text. e.g.
    1. Give a new home to lost sections such as "Errors" and "Assumptions vs Inferences"
    2. Collect and merge listed motivations for sensitivity analysis (currently divided between the opening paragraph and "Applications". Possibly group under "Motivations" heading.
    3. Remove any duplicated information
  2. Re-organise Methodology section, e.g.
    1. Outline the key situations that a practitioner might face - e.g. difficulty of computation expense, dimensionality of model, nonlinearities, correlations, interactions, or the fact that data points may be arbitrarily-placed. Then outline methods that can deal with these situations, clearly categorised into type. E.g. HDMR is essentially a type of emulator, or the fact that sampling-based sensitivity analysis encompasses pretty much all methods except analytical methods. The structure of this section should reflect these facts.
    2. I would add more information about available emulators (in brief, with links), and also link to a new page on Sobol' indices and methods for their calculation. This is because variance-based SA is a core method which is barely mentioned here, but to include it on the main page would make it a very long page.
    3. I would keep the steps to SA but put it under its own subheading and clear up formatting.
    4. Add FAST to the methodology section, currently only linked to at the end.

Overall the suggestions relate to re-organisation and bringing the page up to date with the state of the art. I am posting the suggestions here because I would like the contributors to this page to give their opinions - whether this is a good idea in general, whether individual suggestions sound reasonable, and whether there should be additional changes. If there are no major objections I will start to make changes within a couple of weeks or so, and take on any suggestions or criticisms.

Please post here any opinions on the changes suggested. Thanks. WillBecker (talk) 11:45, 22 August 2012 (UTC)


Ok so I had no comments on the revisions proposed. I have now uploaded my "cleaned up" version of the page. I have tried to re-organise everything in a logical order, delete duplicated information, add more information where appropriate, and include more links. I have also made a new page called Variance-based sensitivity analysis, which is now linked to.

Please post opinions on this. If you are unhappy with the edit and want to make major changes, please discuss it here. I have deleted very little; instead I have moved things to what I believe to be the appropriate places. Thanks WillBecker (talk) 16:43, 30 October 2012 (UTC)

Regression nonlinear in the parameters

[Comment transferred here from User talk:Duoduoduo ]: I agree that linear regression is only linear in the parameters and can therefore cope with nonlinear responses. However, to my knowledge, the application of regression analysis to sensitivity analysis requires the use of standardised regression coefficients. I believe that these are only meaningful when the regression is the most basic simple linear form (i.e. straight lines, planes and hyperplanes). Otherwise if we fit a more complicated model, such as a polynomial, or other basis functions, how do we measure sensitivity? I have not seen a sensitivity analysis so far that uses regression analysis with other basis functions (unless we count emulators, but that relies on variance-based measures of sensitivity). If you can point out where I am wrong on this, please do. WillBecker (talk) 08:39, 4 January 2013 (UTC)

I'll defer to your judgment on this. If you more or less restore the passage I deleted, I hope you can reword it to satisfy these objections I have to it:
  • "Regression analysis can be a very useful tool when the model response is approximately linear," sounds to me like it means the overly broad implication "Regression analysis is not useful when the model response is not approximately linear." Maybe something like this would work: "In regression analysis when the model response is approximately linear, sensitivity analysis can be conducted; however, it is problematic to measure sensitivity when the response is strongly nonlinear."
  • I don't understand the meaning intended in this context of the passage "This can however be identified by the use of the coefficient of determination." I think "This" has no clear antecedent, and I don't see what the coefficient of determination has to do with sensitivity analysis.
Thanks, Duoduoduo (talk) 16:48, 4 January 2013 (UTC)

Ok some good points there. I have reworded the entry to reflect what you have said - please have a look and see if you think it is appropriate. The coefficient of determination is to measure the linearity of the response - if you agree that standardised coefficients require a linear (linear in the data) regression, then if you fit a linear regression to your data and check R^2, you get a measure of linearity - i.e. if it is very low then you would conclude that linear regression is not suitable for the data, and you would try another approach to sensitivity analysis, such as a nonlinear emulator. Conversely, if it is high you would be fairly confident that standardised coefficients are a good measure of sensitivity. If you think it is not necessary to include this, you could remove it. I only mentioned it because I was thinking that it might be useful to someone considering using this method of sensitivity analysis. WillBecker (talk) 10:52, 7 January 2013 (UTC)

Looks good -- I made a few minor changes to it, the main one being to elaborate on the role of the coefficient of determination: If it's large, that makes it likely that the true model really is linear. But if the coefficient of determination is small, the true model could still be linear in the included variable, but with a lot of the variation coming from other sources that are packed into the error term. In the case of a low R2 you can check for linearity or non-linearity by putting in terms in x2 and maybe even x3, and see if t-tests or an F-test say to include or exclude the non-linear terms.
It's been a pleasure working with you on this! Duoduoduo (talk) 15:25, 7 January 2013 (UTC)

Ok, that looks a lot better now. Thank you very much for the input! WillBecker (talk) 15:35, 7 January 2013 (UTC)

R-squared (coefficient of determination) can't distinguish between nonlinearity (curvature) and random variation (scatter about a line), so the statement that " linearity can be confirmed, for instance, if the coefficient of determination is large" (in the "Regression analysis" section) is very misleading. Only very large R^2 values suggest lack of curvature, and such large values are rare in "real-world" data (e.g., outside the physical sciences). - dcljr (talk) 23:25, 11 May 2016 (UTC)

Variance-based methods

The meaning of isn't explained. — Preceding unsigned comment added by 141.30.143.7 (talk) 10:41, 3 September 2014 (UTC)

Thanks for pointing that out, I have now added an explanation. WillBecker (talk) 12:26, 3 September 2014 (UTC)

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VARS neutrality

I have some concerns about the neutrality of the paragraph that presents the VARS methods. It seems to me that this paragraph is not written in an encyclopedia-style but more in a (self?) promotion sytle. It mimics the style of scientific publications, following the typical pattern "Other methods fail to do that, here is the new method that solves all the previous issues". The frequent use of very positive expressions such as "comprehensive illustration of sensitivity information", " As a result, the VARS framework [..] overcomes the scale issue of traditional sensitivity analysis methods", "More importantly", "much lower computational cost than other strategies" does not pertain to the encyclopedia style. Additionally, I believe that the point about low computational requirement is not true, or at least exagerated. This is even more obvious to me that the VARS method is relatively new in the scientific comunity and far from being broadly used or even accepted. On this topic, one can note that the four different references are all from S. Razavi. Last, the sentence "Noteworthy, it has been shown that there is a theoretical link between the VARS framework and the variance-based and derivative-based approaches." needs a reference. To date, I don't think that there is any rigorous proof of that statement. — Preceding unsigned comment added by 132.203.36.91 (talk) 21:40, 27 November 2018 (UTC)

Just uncertainty?

The section starts with "Sensitivity analysis is the study of how the uncertainty in the output of a mathematical model or system (numerical or otherwise) can be apportioned to different sources of uncertainty in its inputs.". I would phrase it as the study about how the variation in output of a mathematical model or system (numerical or otherwise) can be apportioned to the variation of different parameters in its inputs. The influence of uncertainties is just a special case. In e.g. engineering design it is important to know both the influence of design parameters and uncertainties on the output attributes. Furthermore, it does not have to involve any statistical methods, since even a linear differentiation can give plenty of insight. I think that in a strict mathematical sense this is what sensitivity analysis should be, i.e. the derivation of the partial derivatives. I think the subject described in this article should be called "statistical sensitivity analysis" or something like this. — Preceding unsigned comment added by Petkr (talkcontribs) 15:26, 13 February 2019 (UTC)

Work on the section Applications of sensitivity analysis

I have recently tried to clean up the sensitivity analysis page from excessive material uploaded under the section Applications of sensitivity analysis. The applications were on

   Environmental sciences
   Business
   Social sciences
   Chemistry
   Engineering
   Epidemiology
   Meta-analysis
   Multi-criteria decision making
   Time-critical decision making
   Model calibration 

What I did was to create new pages (such as e.g. Applications of sensitivity analysis to environmental sciences moving there the content of the applications, and leaving in the main page Sensitivity Analysis the relative hyperlink. The result was that many of these pages (including the one just mentioned) were immediately taken down for copyright violation and I was myself blamed for the violation. Of course I only copied the material, so I was not responsible for the violations. In the meantime some of the pages have been fixed, e.g. I rewrote completely Applications of sensitivity analysis to environmental sciences. Hope this clarifies my role.

Andrea Saltelli 15:32, 24 August 2020 (UTC)

Just to note, the text is probably still available in the history of this article. There might also be the option of recovering deleted pages via WP:REFUND, but no guarantees. -Kj cheetham (talk) 10:17, 25 August 2020 (UTC)

Copied to Wikipedia or Copied from Wikipedia?

The page of sensitivity analysis has been labeled with the warnings

I am user Andrea Saltelli 15:32, 24 August 2020 (UTC), and was surprised as I have been following this page for a number of years now (since 2006), and though there have been some undisciplined additions (see below) I felt confident that the text as it stands was not the result of a copy from existing material. Thanks to a suggestion from user User:Kj cheetham about what software to use, User:S.lopiano and I looked into the matter.

Using CopyVio detector [1] and looking at the passages highlighted by this tool, one finds this information was previously available on the Wikipedia page rather than in those contributions. Hence, the allegation of plagiarism should rather be on an author from academia rather than on the authors of Wikipedia. Let us have a look at those passages one by one:

i) [T]here are a large number of [and following], found in the book of 2018 of Abdon Atangana [2]. This text has been available on the sensitivity analysis page since one of my first additions on August 19 2008, see [3]

ii) It goes the same for the passage [t]hat of changing one-factor-at-a-time […].

iii) As well as [i]nvolve taking the partial derivative of the output Y with respect to an input factor Xi […]

iv) And [R]egression analysis, in the context of sensitivity analysis […]

v) And [A] class of probabilistic approaches […]

vi) And [S]creening is a particular instance[…]

vii) And [A] simple but useful tool is to plot scatter […]

So it seems that the book author[2] copied entire passages of the content which had been uploaded on the page back in 2008.

Andrea Saltelli 15:32, 24 August 2020 (UTC)

Thank you for looking into that. I have duly removed the tags from the page. Personally I'm surprised the publisher of that book didn't do their own due dilegence of where the material came from. It's not something I've dealt with before, so I'll request assistance. -Kj cheetham (talk) 10:29, 25 August 2020 (UTC)

Is there anything more needed to be done if a book has potentially copied text from Wikipedia? I've not personally checked the book itself. -Kj cheetham (talk) 10:29, 25 August 2020 (UTC)

Kj cheetham, Saltean Yes, there is an action you can take and it will help out editors in the future that discover this overlap in content. Please see BACKWARDSCOPY and the related template {{backwardscopy}}. Placing a note like this on the talk page should help clarify who copied whom. — jmcgnh(talk) (contribs) 04:55, 26 August 2020 (UTC)
Thank you, I've added the tag to the talk page. -Kj cheetham (talk) 08:15, 26 August 2020 (UTC)

References

  1. ^ Text of the query,
  2. ^ a b Abdon Atangana, Fractional Operators with Constant and Variable Order with Application to Geo-Hydrology, 2018, Academic Press, ISBN=978-0-12-809670-3.
  3. ^ See Wikipedia version of 2008.

Merger Discussion

Request received to merge articles: One-factor-at-a-time method into Sensitivity analysis#One-at-a-time_(OAT)

Proposer's Rationale: The source page is not *that* well written, but more importantly seems totally unaware that it falls under the umbrella of sensitivity analysis and is missing quite a bit of context. Either that article needs a lot of TLC, or I would recommend just merging it into the OAT section here. Discuss here. R0uge (talk) 23:29, 1 December 2021 (UTC)

AOT method (sourcing)

At least source 23 "Photosynthetic Control of Atmospheric Carbonyl Sulfide During the Growing Season" (https://doi.org/10.1126%2Fscience.1164015) does not explain the AOT method. It is unclear where the method is used in the article. May also be the case for the two other sources given in the AOT section. 193.48.244.21 (talk) 10:53, 13 March 2023 (UTC)

Top cited articles in sensitivity analysis (bold=number of citations; only articles with more than 1,000 citations reported)

  • Sensitivity analysis in practice: a guide to assessing scientific models, A Saltelli, S Tarantola, F Campolongo, M Ratto, Wiley, 9000, 2004
  • Global sensitivity analysis: the primer, A Saltelli, M Ratto, T Andres, F Campolongo, J Cariboni, D Gatelli, ..., John Wiley & Sons, 7834, 2008
  • Variance based sensitivity analysis of model output. Design and estimator for the total sensitivity index, A Saltelli, P Annoni, I Azzini, F Campolongo, M Ratto, S Tarantola, Computer physics communications 181 (2), 259-270, 3051 2010
  • A quantitative model-independent method for global sensitivity analysis of model output, A Saltelli, S Tarantola, KPS Chan, Technometrics, 39-56, 2532 1999
  • Importance measures in global sensitivity analysis of nonlinear models, T Homma, A Saltelli, Reliability Engineering & System Safety 52 (1), 1-17, 2237 1996
  • Making best use of model evaluations to compute sensitivity indices, A Saltelli, Computer physics communications 145 (2), 280-297, 2196 2002
  • An effective screening design for sensitivity analysis of large models, F Campolongo, J Cariboni, A Saltelli, Environmental modelling & software 22 (10), 1509-1518, 2052 2007
  • Sensitivity analysis for importance assessment, A Saltelli, Risk analysis 22 (3), 579-590, 1478 2002
  • Sensitivity analysis as an ingredient of modeling, A Saltelli, S Tarantola, F Campolongo, Statistical science, 377-395, 1127 2000
  • How to avoid a perfunctory sensitivity analysis, A Saltelli, P Annoni, Environmental Modelling & Software 25 (12), 1508-1517, 1124 2010

Andrea Saltelli Saltean (talk) 10:18, 8 January 2024 (UTC)

Discussing a recent editing of this page by User talk:MrOllie

This is a suggestion for improvement of the page, following an intervention of User talk:MrOllie. In this page, as well as in the other pages he/she has visited last September, i.e. Sensitivity auditing, Sociology of quantification, Ethics of quantification, Post-normal science, Quantitative storytelling and others, the intervention could use some form of revision. As per this page, if one cares to look at Google Scholar one will see that the reference that have been censored are relevant references to the discipline of sensitivity analysis – more precisely they are those with the most citations (see below). Although I did not create this page, I was deeply involved in its development, acting as the Wikipedia editor for a nascent community. The figures on the page were likewise uploaded by myself, as can be easily verified. When the page became too large, I fully restructured it in 2020, for which I incurred serious problems with Wikipedia 's editors, as it seemed that I had plagiarized an existing book. Luckily, I could prove that the opposite was the case, and that it was the book that plagiarized Wikipedia. For having resolved this case, I received the encomium below.

The Barnstar of Diligence
For your investigatory work on Sensitivity analysis. Kj cheetham (talk) 10:20, 25 August 2020 (UTC)

I reported the story to document my involvement in the maintenance of this page. Going back to the intervention of User talk:MrOllie on this page, I note that having removed all my articles (with my co-authors), the editor paradoxically acted as an hypothetical 'rival' academician who wanted to deface the contribution of an author and of his school. This operated a sort of damnatio memoriae, totally outside academia. Removing the most cited handbooks of sensitivity analysis (see below) makes this Wikipedia page less useful for the readers and ultimately biased. Primary sources have been removed, including for the definition of global sensitivity analysis itself. The elision of the SAMO conference series, that now foresees an 11th installment in Grenoble in 2025, likewise deprives a large community of users of an actionable piece of information – i.e. a new researcher joining the community may plan an abstract for the next conference-[1] Wikipedia being a living encyclopaedia. Since I am certain that the intention of User talk:MrOllie was not rewrite the history of the field nor to bias Wikipedia, but only to fix a conflict of interest, I suggest a civilized solution is found to this problem, for which I welcome your suggestions. Saltean (talk) 10:18, 8 January 2024 (UTC)

Input to this discussion

Hello User:MrOllie and User:Saltean - I would like to give some input here as someone who has contributed quite significantly to this page, albeit some years ago.

User:MrOllie I understand and agree with your efforts to check self-citations. However I think this needs to be done with discretion. In this case, User:Saltean is one of the most well-known academics in the field of sensitivity analysis, so removing all citations to his work makes very little sense. I would strongly support reinstating at least some of the references mentioned below, many of which are key texts used by students and academics, as well as important papers in the history of sensitivity analysis, and add value to the page. I say this as an academic who has worked in the field for 15+ years. To be transparent, I do know User:Saltean personally, but I am intervening here on the grounds of fairness and maintaining the quality of the page. I am sure with some discussion we can find a balanced solution. WillBecker (talk) 07:45, 19 January 2024 (UTC)

Welcome back after your 7 year absence. The balanced solution is a sample one - just respect the process for COI editors going forward. Key texts used by students and academics will likely be recognized as such even by folks who are not Saltean themself or personally acquiainted with them, and those folks should be the ones adding the citations. MrOllie (talk) 13:28, 19 January 2024 (UTC)
Thank you for your warm welcome.
According to the COI guidelines on self-citation: "Using material you have written or published is allowed within reason, but only if it is relevant, conforms to the content policies, including WP:SELFPUB, and is not excessive."
This means that it is not against policy to cite yourself, as long as it is not excessive (I think some citations are justified) and it is relevant (the citations definitely are). So what grounds do you have to delete everything? WillBecker (talk) 14:00, 19 January 2024 (UTC)
In this case the self-citation was excessive, that is why I removed them. And given the history of excess self-citation, the recommended process should be followed going forward. MrOllie (talk) 14:02, 19 January 2024 (UTC)
Ok so presumably it is OK to put some back then. WillBecker (talk) 14:04, 19 January 2024 (UTC)
We'll see what someone who is independent thinks about that. MrOllie (talk) 14:05, 19 January 2024 (UTC)
Thank you Mr Ollie for your input to the sensitivity analysis page on Wikipedia.
I had the privilege of an extensive collaboration with Andrea Saltelli for several years at the Joint Research Centre of the European Commission. From my perspective, the material originally included in the Wikipedia page was of high quality. The text adequately captured the essence of sensitivity analysis as a discipline. The comprehensive overview provided in the initial text showcased a remarkable understanding of the subject matter, presenting a balanced perspective that encompassed a wide array of methodologies.
The citations included were, in my opinion, valid and contributed to a balanced reference of research advancements in the field. It is important to acknowledge that Mr. Saltelli holds a prominent position as one of the most cited researchers in sensitivity analysis. The inclusion of his insights and perspectives in the original text added to the quality of the Wikipedia page.
In my opinion, the initial version of the Wikipedia page offered a comprehensive, well-balanced, and highly credible portrayal of sensitivity analysis. It effectively provided readers with a solid foundation to explore the subject further.
In light of these observations, I advocate for preserving the original material and ensuring that its integrity and comprehensiveness are maintained.
Stefano Tarantola Stefano Tarantola (talk) 11:06, 22 January 2024 (UTC)
This is looking like a case of WP:CANVASS at this point. If you have been contacted off-wiki and asked to comment here, than in itself is a violation of Wikipedia's policies. Testimonials from more people with conflicts of interest are not helpful to this process. MrOllie (talk) 13:44, 22 January 2024 (UTC)
Thanks. As you said, let's see what someone who is independent thinks about that. Please see also User_talk:Robert_McClenon#Closed_discussion_Sensitivity_Analysis. Regards. Andrea Saltelli Saltean (talk) 14:04, 22 January 2024 (UTC)
Did you contact people outside of Wikipedia and inform them about this discussion? MrOllie (talk) 14:08, 22 January 2024 (UTC)
Dear Mr Ollie,
It seems you are relentless targeting Mr. Saltelli. Let's be objective: Saltelli has published over 100 articles on sensitivity analysis in highly reputable scientific journals. His publications have been cited 22,000 times according to Google Scholar. It is only natural that he would have numerous references on the Wikipedia page.
I hope this discussion can end and we can use our time in a more productive way.
kind regards,
Stefano Stefano Tarantola (talk) 09:02, 23 January 2024 (UTC)

In support of the change revert

I, Pamphile T. Roy, support the proposal to revert the changes. I hold a PhD in Sensitivity Analysis and Quasi-Monte Carlo, I am a maintainer of SALib (the most important Python library for Sensitivity Analysis) and SciPy (one of the most used Python library in Science). I also added the Sobol' method to SciPy along all the QMC capabilities.

Some rational if needed:

  • The visualisation aspect of Sensitivity Analysis is always left out while it's paramount and provide new insights
  • All the comments about OAT, FAST, etc. are very important, factual, relevant and provide invaluable practical advise to practitioners.

While a lot of citations are self-citations, this is simply reflecting the state of our field. Prof. Saltelli is a brilliant researcher and made invaluable contributions to the field that he arguably co-created.

His outstanding contributions should not be undermined and Wikipedia should be thankful that he is taking the time to share his knowledge.

I also suffered from reverts on Wiki (lastly to fix the orthography of Prof. Sobol') and I find it sad that, we, the top researchers in the field itself, are receiving such a heavy push back. Tupui (talk) 18:28, 21 January 2024 (UTC)


I, Sergei Kucherenko, support the proposal to revert the changes. With nearly 25 years of experience in Sensitivity Analysis within academia (Imperial College London, UK), I, along with my collaborators and students, consistently relied on books and papers authored or co-authored by Andrea Saltelli for both teaching and research. A comprehensive Wikipedia article on Sensitivity Analysis should unquestionably include references to his significant and valuable publications. — Preceding unsigned comment added by Skuchr (talkcontribs) 11:19, 23 January 2024 (UTC)

  • Oppose revert Wikipedia's not an arbiter of what is the truth, but what is verifiable. We go by what is represented in secondary sources with a reputation for fact-checking and transparency, not assertions of expertise, even when quite clearly true in this case. CoffeeCrumbs (talk) 15:28, 26 February 2024 (UTC)