[R-sig-Geo] Shiny app for Spatial Econometric classes
Roger Bivand
Roger@B|v@nd @end|ng |rom nhh@no
Fri Jul 9 16:30:14 CEST 2021
Returning to the "Tobler" shiny app:
The main serious weakness is the name and the approach. It is not and has
never been the case that "Everything is related to everything else, but
near things are more related than distant things." This is and has always
been an oversimplification, disguising the underlying entitation/support
problem. Are the units of observation appropriate for the scale of the
unobserved spatial process?
Tobler (1970) https://doi.org/10.2307/143141 was published in the same SI
as Olsson (1970) https://doi.org/10.2307/143140 (Olsson precedes Tobler),
but Olsson does grasp the important point that spatial autocorrelation is
not immanent in spatial phenomena, but often is engendered by
inappropriate entitation, by omitted variables and/or inappropriate
functional form. The key quote from Olsson is on p. 228:
"The existence of such autocorrelations makes it tempting to agree with
Tobler (1970, 236 [my interpolation, the original refers to a conference
paper]) that 'everything is related to everything else, but near things
are more related than distant things.' On the other hand, the fact that
the autocorrelations seem to hide systematic specification errors suggests
that the elevation of this statement to the status of 'the first law of
geography' is at best premature. At worst, the statement may represent the
spatial variant of the post hoc fallacy, which would mean that
coinincidence has been mistaken for a causal relation."
The status of the "first law" is very similar to the belief that John Snow
induced the cause of cholera as water-borne from a map. It may be a good
way of selling GIS, but it isn't accurate; Snow had a strong working
microbiological hypothesis prior to visiting Soho, and the map was
prepared after the Broad street pump was disabled as documentation that
the hypothesis held (see https://doi.org/10.1016/s0140-6736(00)02442-9
Brody et al. 2000).
So the framing of the shiny app is unfortunate, and spatial econometrics
is not a toolbox, rather a way of loooking at mis-specification when space
is involved, I think.
Hope this isn't too critical,
Roger
On Thu, 8 Jul 2021, Raphael Saldanha wrote:
> Estimado Spencer,
>
> Thanks for your kind words. Actually, that construction is not standard
> in Portuguese also (although that does not sound pedant or with some bad
> intention for our ears). I revised the text three times and used an app
> for grammar correction before sending. Anyway, it was a mistake by all
> means.
>
> To learn Spatial Econometrics and other fields require from us
> additional efforts. There is just a few books or materials in
> Portuguese. But I try to approach this difficult as an opportunity to
> learn.
>
> Indeed, one of the reasons for building the app was to facilitate the
> use of the methods for people that are learning R. *Professor Eduardo
> and I* teach annually a course on that field and we face this challenge.
> With the pandemics and Zoom classes, we hope that the app and our
> scripts will help the students to learn R.
>
>
> Um forte abraço,
>
> Raphael Saldanha
>
>> Em 8 de jul. de 2021, à(s) 08:45, Spencer Graves <spencer.graves using prodsyse.com> escreveu:
>>
>> Estimado Raphael:
>>
>>
>> I don't know any Portuguese either, and I'm very grateful that you've made the effort to ask this group in a language not your own.
>>
>>
>> In primary school, I learned that constructions like, "Me and Professor ..." too often sounded like, "Mean Professor ...".
>>
>>
>> Un fuerte abrazo ("A big hug", as a Uruguayan man whom I had not previously met ended a letter inviting me to talk at a conference).
>>
>>
>> Spencer Graves
>>
>>
>> On 7/8/21 5:32 AM, Raphael Saldanha wrote:
>>> No offense taken. Thanks for the remark and opportunity to learn.
>>> Cheers,
>>> Raphael
>>>> Em 7 de jul. de 2021, à(s) 23:20, Rolf Turner <r.turner using auckland.ac.nz> escreveu:
>>>>
>>>>
>>>>> On Wed, 7 Jul 2021 18:09:50 -0300
>>>>> Raphael Saldanha <rfsaldanha using gmail.com> wrote:
>>>>>
>>>>> Hello all!
>>>>>
>>>>> Me and Professor Eduardo Almeida (UFJF, Brazil) are creating an R
>>>>> Shiny app for Spatial Econometric classes.
>>>>
>>>> <SNIP>
>>>>
>>>> I hope that you won't find this comment offensive, but I could not
>>>> resist sending it to you, since I am rather fanatical (pedantic?) about
>>>> correct English usage.
>>>>
>>>> The expression "Me and Professor Eduardo Almeida" is both (a) bad
>>>> grammar and (b) bad form. (a) Instead of the pronoun "Me" (accusative or
>>>> objective case) you should use "I" (nominative or subjective case), since
>>>> this expression is the subject of the sentence. (b) It is "bad form"
>>>> (it sounds vaguely self-promoting) to put a first person pronoun before the
>>>> names of others to which it is linked. You should say "Professor
>>>> Eduardo Almeida and I are creating ....".
>>>>
>>>> I realise that English is surely a second language for you, and your
>>>> English is infinitely better than my non-existent Portuguese. Your
>>>> English is actually quite good, probably better than that of many
>>>> native English speakers. Nevertheless the expression that you use is
>>>> not correct and you should strive to avoid such usage.
>>>>
>>>> Again let me express the hope that you won't take offence at this
>>>> comment.
>>>>
>>>> cheers,
>>>>
>>>> Rolf Turner
>>>>
>>>> --
>>>> Honorary Research Fellow
>>>> Department of Statistics
>>>> University of Auckland
>>>> Phone: +64-9-373-7599 ext. 88276
>>>>
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>
>
--
Roger Bivand
Emeritus Professor
Department of Economics, Norwegian School of Economics,
Postboks 3490 Ytre Sandviken, 5045 Bergen, Norway.
e-mail: Roger.Bivand using nhh.no
https://orcid.org/0000-0003-2392-6140
https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en
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