Wikidata:Database reports/identical birth and death dates

These are pairs of items with identical dates in date of birth (P569) and date of death (P570). Some should be merged (duplicates), others not: different persons with the same dates (coincidence or virtual twins) or incorrect dates (mixup).

The list is updated regularly (daily?) by bot (items with corrected or removed dates can take a few days to be removed from the list).

How probable are false positives?

  • (A) Items for people with both dates: 2,998,367 ref
  • (B) Items for people with two people with the same date of birth and date of death (Q20978290): 3,121 ref
  • Ratio (B/A): 1.04 ‰
  • (C) There are 299,025 ref redirects to items with both dates, i.e. two items were merged
  • Ratio (C/A): 9.97 %
  • False positives (B/C): 1.04 % (This underestimates it as it assumes that all items had both dates before being merged).

Items in the list below could be:

Type Sample Suggested approach
Items about the same person merge the two items
Items about the same person merge the two items
Items about the same person delete the redirect-sitelink and merge the two items. Special:MergeItems can sometimes merge them directly.
Items about the same person merge the two items
Items about the same person delete the sitelink to the disambiguation page and merge the two items (sitelink didn't get updated on pagemove)
find a new item for the disambiguation page or create it
Items about likely about the same person, but this isn't conclusive add said to be the same as (P460) to each, do not merge them
Items about different people, with incorrect dates and possibly mixed-up sitelinks correct dates and/or fix sitelinks. Don't merge. If in doubt, use the articles' talk pages or WD:IWC
Items about a person and items with dates they shouldn't have remove dates from the item that shouldn't have them
Items for identical persons, but with two articles at the same Wikipedia possibly suggest to Wikipedia to merge both adding Template:Merge (Q6919004) to each article
mark one with instance of (P31): Wikimedia duplicated page (Q17362920) and qualifier of (P642) linking to the other item
Alternatively, interlink both with said to be the same as (P460)
possibly move statements to the one item that isn't marked with Wikimedia duplicated page (Q17362920)
Once the merge of the articles completed, the items can be merged
False positives: two different persons, with same dates of birth and death

double-check dates, ideally with references
interlink both items with different from (P1889) and qualify with criterion used (P1013) = two people with the same date of birth and date of death (Q20978290)
add items to False_positives

Already merged/fixed some of the below (items redirected, labels and statements appear then as identical) do nothing ;)

Steps:

  • Are both items about the same person?
    • If yes:
      • Can the items be merged?
        • If yes: merge them. In the next update, the pair will disappear from the list
        • If no: tag the two articles at Wikipedia for merging. In the next update, the pair will be moved to the "marked for merging" section of the main list.
    • If no:
      • Are the instance of (P31) values correct?
        • If no: correct them
      • Should the item have date of birth (P569)/date of death (P570)?
        • If no: remove them. In one of the next updates, the pair will disappear from the list.
      • Are the dates correct?
        • If no: correct them. In one of the next updates, the pair will disappear from the list.
        • If yes: add the pair to "false positives". In the next update, the pair will disappear from the list.

Update frequency:

  • Removal of merged items: generally daily
  • Removal of items marked as different: generally daily
  • Removal of items with corrected dates: generally weekly (based on Wikidata dumps)
  • Merge of items identified as duplicates and marked for merging at a Wikipedia (if they still include identical dates): occasionally by bot once the merger at Wikipedia is completed.
  • Addition of newly identified items: generally weekly (based on Wikidata dumps)

Tools:

Can be merged edit

Sitelink conflicts edit

Sitelink conflicts, marked to merge edit

Can be merged edit

Sitelink conflicts edit

Sitelink conflicts, marked to merge edit

False positives edit

DOBDOD Merged Person 1 Person 2 P31 (#1) P31 (#2) P21 (#1) P21 (#2) P27 (#1) P27 (#2) P106 (#1) P106 (#2) Diff from TO DO