View source for Known Issues With LinkedEarth Representation of the PAGES2k Dataset

This page lists the issue identified with the representation of the PAGES2k dataset in LinkedEarth. 

== Ghost measured variables ==

Because the [[LinkedEarth Ontology]] requires the representation of the [[:Category:ProxyArchive (L) | archive type]] to be made on a [[:Category:MeasuredVariable (L)| measured variable]], it was decided to create "ghost" measured variable if only the [[:Category:InferredVariable (L) | inferred variables]] were archived. The following datastes have improperly set the [[:Category:InferredVariable (L) | inferred variable]] to a [[:Category:MeasuredVariable (L) | measured variable]] with a [[:Property:ProxyObservationType (L)]] set to "Ghostmeasured". 

Instead, these datasets should have an additional entry in the JSON-LD file with the proper [[:Property:ProxyObservationType (L)]].

{{#ask:
[[Category:DataTable_(L)]]
[[IncludesVariable_(L).ProxyObservationType_(L)::GhostMeasured]]
|limit =10
|format = broadtable
}}

==Earliest Sample Date/Latest Sample Date == 

The period covered by the record should be provided at the [[:Category:Variable (L) | variable]] level through the [[:Property:HasMinValue (L) | HasMinValue]] and [[:Property:HasMaxValue (L) | HasMaxValue]] properties.

===EarliestSampleDate===

{{#ask:
[[Category:Dataset_(L)]]
[[EarliestSampleDate::+]]
|limit =10
|format = broadtable
}}


===LastestSampleDate===

{{#ask:
[[Category:Dataset_(L)]]
[[LatestSampleDate::+]]
|limit =10
|format = broadtable
}}

== Calibration models on measured Variable ==

The newest version of the [[LinkedEarth Ontology]] should only allow the calibration model to be attached to an [[:Category:InferredVariable (L) | inferred variable]] through the property [[:Property:CalibratedVia (L) | calibratedVia]]. Some PAGES2k datasets have information relating to calibration on the [[:Category:MeasuredVariable (L) | measured variable]].

{{#ask:
[[Category:MeasuredVariable_(L)]]
[[CalibratedVia (L)::+]]
|limit =10
|format = broadtable
}}

== Improper naming of ProxyObservationType ==

Some types have a number after them probably lifted from the name. Should be removed. This inlude:
* d18O1
* calcification 1,2,3,4,5,6,7
* count (1 thru 18)
* trsgi (1 thru 4)
* temperature (1 thru 3)

In addition, uncertainty_temperature and notes should not be [[:Property:ProxyObservationType (L) |  types of proxy observations]].

=== Improper formating for trace element names ===

The [[LinkedEarth Ontology]] uses the proper "/" for trace elements rather than a space as used by PAGES 2k, therefore "Mg Ca" should be "[[Mg/Ca]]". 

==== Mg/Ca ====

{{#ask:
[[Category:DataTable_(L)]]
[[IncludesVariable_(L).ProxyObservationType_(L)::Mg Ca]]
|limit =10
|format = broadtable
}}


==== Sr/Ca ====

{{#ask:
[[Category:DataTable_(L)]]
[[IncludesVariable_(L).ProxyObservationType_(L)::Sr Ca]]
|limit =10
|format = broadtable
}}


==== C/N ====

{{#ask:
[[Category:DataTable_(L)]]
[[IncludesVariable_(L).ProxyObservationType_(L)::C N]]
|limit =10
|format = broadtable
}}

== SensorSpecies placed under the variable category ==

In the [[LinkedEarth Ontology]], the proper path is [[:Category:MeasuredVariable (L)]] -> [[:Property:HasProxySystem (L)]] -> [[:Category:ProxySystem (L)]] -> [[:Property: ProxySensorType (L)]] -> [[:Category:ProxySensor (L)]] -> [[:Property:SensorSpecies (L)]].

'''Note:''' This may be a problem with the mapping rather than the PAGES2k [[Linked Paleo Data | LiPD]] files.

{{#ask:
[[Category:DataTable_(L)]]
[[IncludesVariable_(L).SensorSpecies_(L)::+]]
|limit =10
|format = broadtable
}}

== Physical Sample ==

For most datasets, the name of the physical sample doesn't correspond to anything. In some instances, it's just an fancier name for the timeseries. Should be removed.

== LiPD version mixture ==

Some files have shown to have an invalid mixture of LiPD v1.2 and v.1.3 structures. The known issue so far is ensemble tables are an incorrect data type. In v1.2, ensemble tables are a fixed single entry for one table. In v1.3, ensemble tables are an array of multiple possible entries for multiple tables. Files downloaded from the Wiki have ensemble arrays as per v1.3, but have other characteristics of v1.2 like "chronModel", "chronMesurementTable", "chronDataTableName" and other discontinued keys. 


[[Arc-Agassiz.Vinther.2008]]