# Wikidata:Property proposal/Natural science

 Before proposing a property Check if the property already exists by looking at Wikidata:List of properties (research on manual list) and Special:ListProperties. Check if the property was previously proposed or is on the pending list. Check if you can give a similar label and definition as an existing Wikipedia infobox parameter, or if it can be matched to an infobox, to or from which data can be transferred automatically. Select the right datatype for the property. Start writing the documentation based on the preload form below and add it in the appropriate section.Creating the property Once consensus is reached, change status=ready on the template, to attract the attention of a property creator. Creation can be done 1 week after the proposal, by a property creator or an administrator. See steps when creating properties.
 On this page, old discussions are archived. An overview of all archives can be found at this page's archive index. The current archive is located at 2019/07.

## Biology

### Insects (Insecta) of the World ID

Under discussion

#### Motivation

A very important database for Australian taxa. Interestingly, for plant taxa it instead pipes APNI ID (P5984) a URL constructor, so this property will not apply to plants. Plants can be found using APNI ID (P5984) and a third-party formatter URL (P3303) which I have added to that property. But this proposal should apply to any non-plant taxa. -- 99of9 (talk) 07:56, 3 July 2019 (UTC)

Following feedback below, I have dug into the variety of different identifier formats they use (see the large file download at https://bie.ala.org.au/search?q=&fq=idxtype:"TAXON"). So I'm now proposing to generalise this property to accept all of their taxon identifiers. --99of9 (talk) 03:01, 5 July 2019 (UTC)

#### Discussion

•   Comment This will be extremely useful! Ambrosia10 (talk) 09:16, 3 July 2019 (UTC) In light of what has been explained below I regret to say I am withdrawing my unconditional support. This seems a shame, as I find Atlas of Living Australia extremely helpful and would very much like to add their external identifiers to taxon items so that others might benefit from the links. If only their identifiers were persistent. Ambrosia10 (talk) 10:57, 3 July 2019 (UTC)
•   Comment My concern is that these identifiers are not persistent, the Atlas of Living Australia can change them at anytime. If you look at the web page for Example 2 you can see a series of identifiers labelled “Previous AFD LSID”. Each of these would have been the ALA identifier at some point in the past (I encountered this problem of identifiers changing while building Ozymandias: a biodiversity knowledge graph (Q63687022)). I don’t know what Wikidata’s policy is on identifiers that can change, so maybe this isn’t an issue, but it will complicate the lives of anyone relying on these identifiers being persistent. --Rdmpage (talk) 10:30, 3 July 2019 (UTC)
• Wow, I hadn't spotted that, thanks. I'll investigate whether using the alternative format: https://bie.ala.org.au/species/urn:lsid:biodiversity.org.au:afd.name:320977 works better. That appears not to shift when the URNs change. The number 320977 seems to come from the Australian Faunal Directory, but I can't see where they are listed, so I'd like to better understand. Any clues would be gratefully accepted. --99of9 (talk) 12:09, 3 July 2019 (UTC)
• But the afd.name ids are for taxonomic names NOT taxa so they aren’t the same thing (although they are often conflated). Wikidata itself conflates the two, but I suspect it may be too late to undo this. I presume the reason ALA identifiers change is that some researchers argue that if our notion of a taxon changes then that taxon “concept” should have a new identifier. There is logic to that approach, but it makes linking to taxa harder. Note that I’m not arguing against having ALA identifiers, just trying to clarify their properties. I don’t know whether there are other examples of Wikidata identifiers that change overtime, and whether there are mechanisms to track those changes. --Rdmpage (talk) 12:41, 3 July 2019 (UTC)
• My understanding of this URL format is "get the ALA taxon associated with the afd.name with the index 320977", which ends up with a taxon. Certainly if you click the link in my previous comment, there is no clue that the page you get to is not about a taxon. --99of9 (talk) 12:46, 3 July 2019 (UTC)
• Regarding identifiers that change with time. An example where it works ok is ComLaw ID (P2461) which changes every time an act of parliament is amended by a later act. So for example Australian Security Intelligence Organisation Act 1979 (Q4824660) has a long list of values, with start and end dates. However, this works best when URLs with old IDs still give useful info (e.g. here they link to the pre-amendment act). For ALA, I think I'd rather not maintain a list of unpredictably broken links. --99of9 (talk) 12:52, 3 July 2019 (UTC)
•   Support David (talk) 06:41, 4 July 2019 (UTC)

#### Motivation

Solid list of Algal taxa maintained by an official organization. 99of9 (talk) 13:08, 17 July 2019 (UTC)

#### Discussion

Notified participants of WikiProject Australia --99of9 (talk) 13:10, 17 July 2019 (UTC)

Notified participants of WikiProject Taxonomy --99of9 (talk) 13:10, 17 July 2019 (UTC)

### ABBBS Taxon ID

Under discussion

#### Motivation

Chemical hazards database for common workplace substances, maintained by a Government organization. 99of9 (talk) 07:07, 9 July 2019 (UTC)

#### Discussion

Notified participants of WikiProject Australia --99of9 (talk) 07:07, 9 July 2019 (UTC)

Notified participants of WikiProject Chemistry --99of9 (talk) 07:08, 9 July 2019 (UTC)

•   Support David (talk) 07:15, 9 July 2019 (UTC)
•   Support (Good move!) MargaretRDonald (talk) 07:20, 9 July 2019 (UTC)
•   Support Looks good to me. --Egon Willighagen (talk) 07:38, 9 July 2019 (UTC)
•   Support Dhx1 (talk) 11:31, 9 July 2019 (UTC)
•   Support useful --Leiem (talk) 11:58, 9 July 2019 (UTC)
•   Support --Trade (talk) 21:44, 9 July 2019 (UTC)
•   Support Nickw25 (talk) 09:15, 10 July 2019 (UTC)
•   Support Ok to import that ID for chemical compound (pure form), but for mixture like hydrogen peroxide solution I think we need to discuss first how to handle the composition problem. Snipre (talk) 12:16, 10 July 2019 (UTC)
@Snipre: but if you follow the link from our (unspecified concentration) item to their (unspecified %) item, you get "at various concentrations and, therefore, these solutions require different classification and labelling since the hazards vary at different concentrations", which seems quite reasonable when talking about a variety of concentrations. So I still think our item would be enriched by a link to their item. --99of9 (talk) 12:52, 10 July 2019 (UTC)
@99of9: But other databases or classifications have different assessment of mixture according to its concentration. I want to avoid a mass creation of new items for mixture to be able to import the HCIS ID and later to have to rename or merge them because we have to improve the definition to handle other classification of IDs. Snipre (talk) 08:30, 16 July 2019 (UTC)
•   Support --DannyS712 (talk) 14:07, 10 July 2019 (UTC)
•   Support --Hugo (talk) 03:38, 16 July 2019 (UTC)
•   Support Cwf97 (talk) 20:45, 16 July 2019 (EST)

@ديفيد عادل وهبة خليل 2, Leiem, MargaretRDonald, Nickw25, DannyS712, Trade: @Snipre, Hugo, Cwf97, Egon Willighagen, 99of9, Dhx1:   Done: HCIS ID (P7025). − Pintoch (talk) 17:16, 20 July 2019 (UTC)

### AICS Chemical ID

#### Motivation

Another reputable database with solid IDs for items which don't have many. 99of9 (talk) 07:40, 9 July 2019 (UTC)

#### Discussion

Notified participants of WikiProject Australia --99of9 (talk) 07:40, 9 July 2019 (UTC)

Notified participants of WikiProject New Zealand --99of9 (talk) 07:40, 9 July 2019 (UTC)

Notified participants of WikiProject Medicine --99of9 (talk) 07:41, 9 July 2019 (UTC)

@Bluerasberry, ديفيد عادل وهبة خليل 2, MargaretRDonald, Csisc, Nickw25, DannyS712: @Trade, Tibbs001, 99of9, Dhx1:   Done: ANZCTR ID (P7019). − Pintoch (talk) 17:15, 20 July 2019 (UTC)

### PBS Manufacturer ID

#### Motivation

Current IDs for rivers don't provide much info apart from the location. This gives river cross sections and charts water flow and levels over time. 99of9 (talk) 14:12, 17 July 2019 (UTC)

#### Discussion

Notified participants of WikiProject Australia --99of9 (talk) 14:12, 17 July 2019 (UTC)

•   Support. I also updated the regex to use "+" instead of "*". In other words, empty values aren't allowed. Dhx1 (talk) 14:27, 17 July 2019 (UTC)
Thanks for your support. The leading [1-9] will ensure the string is not empty. The extra \d characters could in principle be unused. --99of9 (talk) 14:36, 17 July 2019 (UTC)
@99of9: Oops I completely misread the first regex. Thanks for reverting! Dhx1 (talk) 15:21, 17 July 2019 (UTC)
•   Support. Good to have our most important resource, water, better identified. Oronsay (talk) 20:03, 17 July 2019 (UTC)
•   Support MargaretRDonald (talk) 20:24, 17 July 2019 (UTC)
•   Support. Will be very useful. Lots of ambiguity around stream names in enwiki at least. A unique identifier will help (at least for NSW). -- Mattinbgn (talk) 22:56, 17 July 2019 (UTC)
•   Support David (talk) 06:27, 18 July 2019 (UTC)
•   Support --Trade (talk) 11:49, 20 July 2019 (UTC)

## Mathematics

### in defining formula

Under discussion
Description symbol used for this in defining formula Mathematical expression items with defining formula (P2534), calculated from (P4934) part of value of defining formula (P2534) f-number (Q862169) calculated from (P4934) focal length (Q193540) → ${\displaystyle {f}}$ f-number (Q862169) calculated from (P4934) diameter of the entrance pupil (Q63572027) → ${\displaystyle {D}}$ f-number (Q862169) → ${\displaystyle N}$ note for samples 1/2/3: f-number (Q862169) has defining formula (P2534) ${\displaystyle N={\frac {f}{D}}}$ eventually complete when P4934 can be defined defining formula (P2534), calculated from (P4934)

#### Motivation

Seems to be missing information about P2534 (Add your motivation for this property here.) --- Jura 10:31, 1 June 2019 (UTC)

#### Discussion

• To bo honest, I do not really understand the proposal. How does it compare to the has part annotations that are used for example in https://www.wikidata.org/wiki/Q35875?--Physikerwelt (talk) 17:29, 3 June 2019 (UTC)
• I'm not sure. Use of has part (P527) on items with defining formula (P2534) seems pretty random. There are currently 97 items on [5]: they don't appear to be structured. It might work on one or the other item when reading the statement 1-by-1 and knowing in advance what to look for. Also, the proposal might not be suitable for every item about physics. --- Jura 11:30, 6 June 2019 (UTC)
• @Swpb: I just noticed your comment on Property_talk:P416 once more. Maybe you were looking for something in the same direction. --- Jura 04:34, 7 June 2019 (UTC)
I was looking to use quantity symbol (P416). I see no need for this new property. Swpb (talk) 15:27, 7 June 2019 (UTC)
• @Swpb: I don't think it's currently defined as being used that way nor does it appear to be particularly structured to do so. Also, I think it's better to use the same format/datatype. --- Jura 16:28, 7 June 2019 (UTC)
•   Support. Logical property.--Arbnos (talk) 13:55, 19 July 2019 (UTC)

## Base material

### surface roughness

Description component of surface texture quantified by the deviations in the direction of the normal vector of a real surface from its ideal form surface roughness (Q114817) Quantity This proprety request is part of the project of creating an infobox for materials Mechanical property of all solid Materials Any number. Qualifiers : relative to (P2210) (mandatory) + others depending on the use N12 Roughness (Q62034144) : surface roughness (Pxxx) → 50 µm relative to (P2210) → Ra (Q55776776) N12 Roughness (Q62034144) : surface roughness (Pxxx) → 200 µm relative to (P2210) → Rt (Q55776788) stainless steel (Q172587) : coefficient of friction (P5575) → 0,3 with qualifiers surface roughness (Pxxx) → 3,2 µm and relative to (P2210) → Ra (Q55776776) w:Surface roughness Creating an infobox for materials

#### Motivation

This proprety request is part of the project of creating an infobox for materials. To be used as a qualifier for properties such as coefficient of friction, fatigue limit or corrosion resistance. It could also be used as a standalone property for parts, measuring methods, standards or manufacturing processes such as Abrasive blasting (Q917273) with qualifier like the granularity of sand, the velocity and the material. It could also be a geologic property referring to soil surface roughness.

#### Discussion

•   Support David (talk) 07:36, 28 July 2018 (UTC)
•   Support @Thibdx: are you still interested in this? If so could you add qids in the examples so that we can create this? If not, please use |status=withdrawn. − Pintoch (talk) 20:35, 6 March 2019 (UTC)
Hi, @Pintoch:. Added. I'm still interested in this. However now that I have a deeper understanding of Wikidata I'm turning partisan of having more properties but that represent exact scientific concepts and that are not a hood for several measures. In the example 3 the surface roughness is used as a qualifier. But since surface rougness is a general concept and not an exact measure, we need to add the type of measure that was used. The most used is the Ra (Arithmetical mean deviation of the assessed profile). There is also the Rv (Maximum valley depth), Rp (Maximum peak height), Rt (Maximum Height of the Profile), Rz (Average distance between the highest peak and lowest valley in each sampling length)... The problem is that since surface rugosity is used as a qualifier, we cannot add a qualifier of a qualifier to enforce the precision needed. In my opinion this model make general "hood" properties very weak in the context of Wikidata. The molecular biology project had exactly the same problem. First they used the general property physically interacts with (P129) with qualifiers to specify all sort of interactions. For example, if a molecule is an agonist or an antogonist of the target receptor. Then they created the properties agonist of (P3772), antagonist of (P3773), activator of (P3771), disrupting agent for (P3775), inhibitor of (P3776), antisense inhibitor of (P3777), positive allosteric modulator of (P3778), negative allosteric modulator of (P3779)... Now it is a mess in the datasets because some items use the old way and some use the new way... I know that some admins are pushing to limit the number of properties but being not precise enough seems to raise problems in the long term. It is the core problematic in industry, where we have to deal with the hard reality of physics instead of simple concepts. A basic example : many engineers don't know the types of stainless steels. But a martensitic stainless steel react catastrophically to thermo/chemical treatments designed for austenitic stainless steels... I think that we need a general policy at Wikidata level to design properties that have the good level of details. In order to avoid specific details that would only be raised on a couple of items but enough detailled to represent something that is scientifically measured. --Thibdx (talk) 22:14, 12 March 2019 (UTC)

### shrinkage

Description Reduction in the size of something, or the process of becoming smaller, typically when a material return to room temperature after heating. Shrinkage (Q1170964) Quantity This proprety request is part of the project of creating an infobox for materials. base material (Q214609) Any number. direction (P560) maybe used for material with an anisotropic shrinkage. determination method (P459) or fabrication method (P2079) shall be specified. Two temperature (P2076) values are needed except if the process already define it. percentage (Q11229) nylon 6-6 (Q7071155) → 0,1 % with direction (P560) → parallelism (Q53875) and fabrication method (P2079) → injection molding (Q260606) nylon 6-6 (Q7071155) → 0,9 % with direction (P560) → normal (Q273176) and fabrication method (P2079) → injection molding (Q260606) Grivory GM-4H (Q57051271) → 0,8 % with fabrication method (P2079) → injection molding (Q260606) w:Shrinkage Creating an infobox for materials

#### Motivation

Shrinkage is one of the most important information considering the processing of a material. It is needed to define the exact dimensions of the mold. --Thibdx (talk) 21:06, 7 October 2018 (UTC)

#### Discussion

•   Comment from the samples/description, it seems that the proposal needs datatype quantity, not item. I updated that above. --- Jura 11:20, 9 October 2018 (UTC)
• Right. Thanks for the update. --Thibdx (talk) 20:11, 9 October 2018 (UTC)
•   Support, it looks sensible even if I am not knowledgeable in this field − Pintoch (talk) 22:49, 13 January 2019 (UTC)
•   Support.--Vulphere 15:20, 28 May 2019 (UTC)

Comment: this seems very detached from reality: often shrinkage and expansion are reversible. If a block of metal is heated it becomes bigger, if it cools it becomes smaller, and in that case shrinkage and expansion are linked. For natural materials it is different, these often shrink as they dry, but this is different from metals. - Brya (talk) 05:59, 23 June 2019 (UTC)