3.5. Associative Relationships

Associative relationships between one place record to other place records in TGN. Included are various types of ties or connections between places, excluding hierarchical whole/part relationships.

The link is accomplished using the unique IDs for the focus and the target records. For displays, values to identify the related entity may be concatenated using the record-preferred name and other information from the linked record.

The same standard general references that are appropriate for the Descriptive Note may be used to determine which places are related. See 3.4 Descriptive Note.

Related Places are the associative relationships between the focus place record and other place records in TGN. Only clear and direct relationships should be recorded. These direct relationships may be current or historical.

Given that associative relationships is used for retrieval, it is recommended not to make insignificant or repetitive links between Related Places. Relationships should be made only between records that are directly related, but where hierarchical relationships are inappropriate. If a thesaurus is bound together by too many associative relationships between entities that are only loosely or indirectly related, the value of the relationships in retrieval is lost.

Consider this question: If the end-user is interested in retrieving Place X, will he or she also want to retrieve Place Y? If not, avoid making an associative relationship between the two records; consider whether the information about the second place is better expressed in the Descriptive Note or a Display Date.

Related Place is not required. Link to related places as time and editorial priorities allow.

Make links to Related Places when it is useful to the end-user to have a direct cross-reference to the other places. Think in terms of retrieval: Would such a link be useful in research and discovery? If not, do not make a link to the Related Place (instead, you may mention the other place in the Descriptive Note or a Display Date, if warranted).

Confusion Between Two Places

If there is a significant possibility that two places may be confused because they are adjacent to each other, they are coextensive, one place has been moved to another, or places have a direct historical connection (excluding hierarchical relationships), link them as Related Places. In the example below, for the town, Sikión (in Corinth, Greece), the original town was moved 4 kilometers inland to the current site atop two plateaus in 303 BCE, and the old site has since been repopulated and renamed, Kiáton.

• Example:

See 3.5.2 Relationship Type below for further examples of when to make Related Places.

Homographs

If the only cause of potential confusion is that the places have the same or similar names, do not link them as Related Places. The hierarchical position and place types will distinguish the places with homographic names. In such cases, if necessary you may describe the issue regarding the homographic names in the Descriptive Note (see 3.3 Names).

If one place is the historical counterpart to the modern place, particularly if both places have the same name, Link them as Related Places (e.g., for the modern town of Machu Picchu below, which may be confused with the famous ancient site of the same name).

• Example:

  • For the modern town of Machu Picchu.
    Relationship Type: distinguished from
    Related Place: Machupicchu (Cuzco, Per$00u) (deserted settlement)

Variant Names vs. Separate Records

If scholarly opinion is divided as to whether or not one place is the same place as another, make separate records for each place and link them with relationship type: possibly identified as. This typically occurs with historical entities or historical names for extant places. See the example of Sharuhen under 3.5.2 Relationship Type below.

If scholars generally agree that a historical place occupied the same site as a modern place (or another historical place), you may make only one record for the place and include the other names as variant names.

Organizations as Sets of Places

If you are adding a geopolitical entity that comprises a set of places (e.g., the United Nations or the European Union), link to the members as Related Places; do not make hierarchical links to the member places.

If the set of places represents an organization or institution, the entity as a corporate body should be recorded in ULAN, often having the same name; in the ULAN record, link to the TGN record through the ULAN Events fields. In the Events for ULAN, add Event = 12283/associated or 12284/coextensive, and then link to the appropriate TGN record in the Place field for that Event (example in ULAN: http://vocab.getty.edu/page/ulan/500354403).

• Example:

  • Partial list in the end-user view of the TGN record for the European Union.

    

Hierarchical vs. Associative Relationships

Do not make associative relationships when hierarchical relationships are more appropriate. For the administrative divisions of nations, states, empires, and any other entity with centralized power and borders, use the hierarchical relationships rather than Related Places associative relationships.

The decisions regarding when to make a hierarchical vs. an associative relationship should be relatively clear for current entities. For historical entities, look to precedent for similar examples in TGN.

A term or phrase characterizing the relationship between the focus place and the linked place.

Values are chosen from a controlled list comprising a code and phrase. Each code-plus-phrase is linked to another code, which is the reciprocal relationship.

• Example:

  • Partial view of controlled list.

    

It is required to include a Relationship Type for each Related Place.

Choose the specific suitable Relationship Type, if possible. If necessary, use the broad related to as a default.

Link to the Correct Side of the Relationship

Remember that Relationship Types are reciprocal (that is, linked to both records). When you choose a Relationship Type, make sure that the Relationship Type and its counterpart will work from the points of view of both linked records.

For some relationships, the relationship type is the same on both sides of the link; however, for others it is different depending upon which record you are in. Be very careful to choose the correct relationship for the focus record (i.e., the record you are in when you make the relationship). Consider what will make sense when displayed to a user. For example, if you are in the record of a city, the relationship type linking the city to the state is capital of, because the city in the focus record is the capital of the state in the linked record. If you open the record for the linked state, the reciprocal relationship type will be capital is.

Avoid Redundant Links

Do not make relationships between entities that have the relationship expressed in another way; for example, if members of an organization are linked to the organization, do not also link the members to each other. Also, with few exceptions, avoid linking hierarchical children to each other as Related Places (associative relationship).

List of Relationship Types

Apply Relationship Types according to the definitions in the table below.

• 3000 | related to | 3000

  • Related to: General designation for relationships, where no specific relationship is known or appropriate.

• 3001 | distinguished from | 3001

  • Distinguished from: Use when there is some significant reason why the two places are often confused, but they should be distinguished from each other. Use when a given name is sometimes applied to a different geographic area in other classification schemes. Generally applies to states or general regions rather than to inhabited places. May apply to current or historical relationships.

  • Example:

    • For the Ancient Mesopotamian kingdom, Assyria, which is distinct from the Roman Province of the same name.
      Relationship Type: distinguished from
      Related Place: Assyria (Roman Empire) (province)

• 3005 | possibly identified as | 3005

  • Possibly identified as: Use for places, often inhabited places or deserted settlements (rather than states), about which scholars are uncertain whether or not the historical place is on the same site as the modern place. The places may have either different or similar names. (If the places are established as occupying the same site, there should be only one record, with the historical names included as variant names.)

  • Example:

    • In the record for the lost settlement of Sharuhen.
      Relationship Type: possibly identified as
      Related Place: Tel el-Far’ah (As Suwayd$01a’, Syria) (deserted settlement)

• 3101 | adjacent to | 3101

  • Adjacent to: Use when two sites are often confused or mistakenly believed to be the same site, but they are actually adjacent to each other. Generally applies to current relationships.

  • Example:

    • For Saint Paul, Minnesota, USA, linked to its Twin City.
      Relationship Type: adjacent to
      Related Place: Minneapolis (Hennepin county, Minnesota, USA) (inhabited place)

• 3102 | coextensive with | 3102

  • Coextensive with: Use when places have two different place types for different administrative or physical designations, but the places are coextensive (e.g., when an island and a province occupy the same territory); such places may share the same name.

  • Example:

    • For Kings county, New York, USA.
      Relationship Type: coextensive with
      Related Place: Brooklyn (New York, New York, USA) (borough)

• 3110 | meaning/usage overlaps with | 3110

  • Meaning/usage overlaps with: Use when names of two places are associated with slightly or significantly different and overlapping boundaries in different contexts or during different historical periods. For example, sometimes Judaea is considered a synonym with the Holy Land, although in TGN, they are classified as separate places with different boundaries (although boundaries overlap).

  • Example:

    • For Judaea (Israel) (historical region).
      Relationship Type: meaning/usage overlaps with
      Related Place: Holy Land (Asia) (historical region)

• 3317 | member is | 3318
  3318 | member of | 3317

  • Member of / member is: A typical use of this relationship is linking states to a larger set (e.g., an organization) in which the states’ participation is characterized as member. From the organization’s point of view, the relationship type is member is. May be current or historical.

  • Example:

    • For the nation of Austria.
      Relationship Type: member of
      Related Place: United Nations (organization)

• 3201 | capital of | 3202
  3102 | capital is | 3101

  • Capital of / capital is: Use to link a capital city to the entity for which it is or was the capital. May be current or historical.

  • Example:

    • For Lincoln, Lincolnshire, England, was the capital of a Roman Province.
      Relationship Type: capital of
      Related Place: Flavia Caesariensis (Britannia Inferior, Britannia, Roman Empire) (province)

• 3301 | ally of | 3301

  • Ally of: Use for allies that have a direct, important relationship that is not expressed in another way (e.g., for the towns that were members of the Medieval Tuscan Ghibelline and Guelf factions). Do not use this Relationship Type to link long lists of members to all the other members in the long list; in such cases, it is probably more appropriate to make a separate record for the set of places as an organization or association, and link the members to that broader record.

  • Example

    • For Florence, Italy.
      Relationship Type: ally of
      Related Place: Orvieto (Terni province, Umbria, Italy) (inhabited place)
      Display Date: Guelf allies during the 13th and 14th centuries

• 3401 | moved from | 3402
  3402 | moved to | 3401

  • Moved from / moved to: Use for inhabited places that were physically moved from one location to another. For example, due to the threat or occurrence of natural disaster in one location, the flooding of an area due to the construction of a dam, etc. Typically, one of these places will be historical, often a deserted settlement.

  • Example:

    • For Troupville, Georgia, USA.
      Relationship Type: moved to
      Related Place: Valdosta (Lowndes county, Georgia, USA) (inhabited place)

• 3411 | successor of | 3412
  3412 | predecessor of | 3411

  • Successor of / predecessor of: Use for states that occupy similar territory, but one historically followed the other. Typically, at least one of the entities is now a former state.

  • Example:

    • For ancient Persia.
      Relationship Type: predecessor of
      Related Place: Iran (nation)

• 3510 | historical connection | 3510

  • Historical connection: Use for states that have a strong, direct historical link, but the relationship is not necessarily successor of / predecessor of. Do not use for hierarchical whole/part relationships.

  • Example:

    • For the historical region of Guyenne, France.
      Relationship Type: historical connection
      Related Place: Gascogne (France) (historical region)

The Relationship Type controlled list is extensible. If you wish to add another Relationship Type to this list, contact the Vocabulary Program.

Flag indicating the historical status of the relationship to the Related Place.

• Example:

  • For Sousse, Tunisia.

    

• C - Current
• H - Historical
• B - Both
• N/A - Not Applicable
• U - Unknown

Editors should use standard, authoritative sources to determine whether or not a relationship is historical.

Choose the flag appropriate to the relationship. The default flag for the relationship is Current.

• Current: For relationships that still exist, even though they may have been established long ago, use Current.

• Historical: For a relationship that no longer exists, for example because one entity is no longer extant, use Historical.

• Both: For those rare relationships where a place had a relationship to another place for a period of time, the relationship ended, and at a later time was reestablished, use Both.

• N/A: Use N/A if Current or Historical are not appropriate to the situation.

• Unknown: This is the default flag used for loading data, if no other information is provided.

Dates delimiting the relationship between the two places.

• Example:

  • For Reims, France.

    

There are three fields: Display Date, Start Date, and End Date.

Display Date is a free-text field expressed in Unicode…

The assoicated Start Date and End Date must contain valid years. Dates BCE are expressed as negative numbers.

The dates should be determined using the same standard reference works that supply other information about the relationship.

The Display Date for the relationship usually refers to a period or date. However, this field is also used to make notes that do not explicitly reference a date. In such cases, the note would usually implicitly imply a date or datable condition or event. You are required to include a Start Date and End Date with every Display Date, even if they are very broad or estimated.

Display dates are indexed with Start Date and End Date. Start and End Dates are controlled by special formatting; dates BCE are represented by negative numbers.

Dates are not required. However, if you enter data in any of the three fields, you must enter data in all three of the fields.

The dates appear on reciprocal links. That means that the same dates will appear in both records liked via Associative Relationship. Write the Display Dates and assign Start and End Dates so that they will be correct and unambiguous in both records. Repeat the names of the places in the Display Date when necessary to avoid ambiguity, as in the example below.

• Example:

  • In the record for Oceania.
    Relationship Type: distinguished from
    Related Place: South Sea Islands (Pacific Ocean) (islands)
    Display Date: in some classification systems, “Oceania” is considered a synonym for “South Sea Islands”
    Start Date: 1800 End Date: 9999

See also 4.2 Appendix B: Dates and “Dates for Names” in 3.3 Names.

Follow the style of existing Display Dates.

• Examples:

  • For Antigua and Barbuda.
    Relationship Type: member of
    Related Place: Commonwealth of Nations (association)
    Display Date: joined the association in 1981
    Start Date: 1981 End Date: 9999

  • For the deserted settlement, Ocotepeque, Honduras.
    Relationship Type: moved to
    Related Place: Nueva Ocotepeque (inhabited place)
    Display Date: after 1935
    Start Date: 1935 End Date: 1937

  • For the modern nation, Egypt.
    Relationship Type: successor of
    Related Place: Egypt (ancient) (Africa) (nation)
    Display Date: area of the modern nation was the core of the ancient kingdom of Egypt
    Start Date: 1922 End Date: 9999

Do not use an initial capital, unless the word is a proper name.

Do not use full sentences; do not end the display date with a period or any other punctuation.

Ideally, the display date should refer, explicitly or implicitly, to a time period or date associated with the link between the related places.

If a date is uncertain, use a broad or vague designation (e.g., ancient) or other terms such as ca. and probably to express uncertainty (e.g., ca., in the example below).

• Example

  • For Trier (Rheinland-Pfalz, Germany).
    Relationship Type: capital of
    Related Place: Belgica Prima (Gallia Belgica, Gaul) (nation)
    Display Date: from ca. 300 CE
    Start Date: 290 End Date: 450

In some cases, the Display Date may be used to record unusual or important information about the Related Place relationship (see the example below), but not explicitly to a date. However, dates should be implicit in the condition or event mentioned and you should have a period or date in mind, because if you record a Display Date, Start and End dates are also required.

• Example

  • For the former nation of Alashiya.
    Relationship Type: possibly identified as
    Related Place: Cyprus (Asia) (island)
    Display Date: it is possible that the name “Alashiya,” which occurs in Hittite and Egyptian records, refers to Cyprus
    Start Date: -1700 End Date: 9999

Use dates that most broadly delimit the span of time of the relationship referred to in the display date. In many cases, the years will be approximate years. When in doubt, it is better to estimate too broad a span rather than too narrow a span. See 4.2.3 Date Authority for approximate dates of historic events and entities; you should also consult other, related records in TGN to establish dates.

Dates must be expressed in the proleptic Gregorian calendar, which is the Gregorian calendar projected back in time before it came into existence.

Express dates BCE with negative numbers, using a hyphen before the number. Do not use commas or any other punctuation

• Example:

  • For Ankara, Turkey.
    Relationship Type: capital of
    Related Place: Galatia (Turkey) (general region)
    Display Date: from 25 BCE
    Start Date: -25 End Date: 450

For current relationships, use the End Date 9999.

• Example:

  • For the European Union.
    Relationship Type: member is
    Related Place: Republic of Ireland (nation)
    Display Date: since 1973
    Start Date: 1973 End Date: 9999

For very ancient dates, expressed as years ago or before present in the Display Date, translate these dates into approximate years in the proleptic Gregorian calendar for the Start and End Dates.