This is a presentation originally given at the 2013 BYU Conference on Family History and Genealogy and again with updated content for a presentation at the 2017 BYU Conference on Family History. This presentation helps users become more familiar with and successful using the merge-related features of FamilySearch's Family Tree.

1. © 2013 by Intellectual Reserve, Inc. All rights reserved.
Merging People in
FamilySearch Family Tree
BYU Conference on Family History and Genealogy
July 31, 2013
Riverton FamilySearch Library Saturday Seminar
October 19, 2013
Family History Support Missionary Training
November 13, 2013
Sandy Crescent Stake Family History Training
February 20, 2014
Ben Baker
bakerb@familysearch.org

2. Background
• Over 5 years as a Software Engineer at FamilySearch
• Currently work primarily on Family Tree with
responsibilities over merge-related features
• Try to do my own genealogy and help others
• I’m here to learn from real users of our services
• Hope I’ll be able to help you today
• E-mail me (bakerb@familysearch.org) to get a copy of
this presentation or for specific merge-related problems
• Click here for the related printed handout materials

3. Why Merging is Necessary

4. Lots of Inputs + Imperfect Patrons +
Imperfect Algorithms ≈ Lots of Duplication
Ancestral File
Record Extraction
Family Tree
More …

5. What Merge Is
• Removal of a
duplicate copy of the
same real person
• A way to choose the
best conclusions to
improve the data on
the resulting merged
person
What Merge Is Not
• An all-purpose clean
up tool to get rid of
data you don’t like
• The same as a
new.familysearch
combine
• The same as deleting
a person

6. new.familysearch
Combine
Family Tree Merge
A B
A
B
A B
A’ B
Merging B into A will delete
(archive/tombstone) B,
potentially changing A with
some of B’s data.
Combining B into A will result
in A with B as an “inner
person” of A. Data from both
persons is preserved and can
be selected as viewable
values.

7. Delete Person Deleting a person will
delete all relationships that
person was in, orphan any
LDS temple ordinances
and won’t keep a link to the
real person.
Use with care!
Only recommend using
when you’re sure the
person is fictitious (Ex.
wrong gender)
Often, a relationship should
be deleted or a merge
should be done.
Man Wife
WifeMan

8. Merge Process Overview

10. Review the persons in the list and take an appropriate action:
1. If there are people in the list that look like they may be the
same real person, click on the Review Merge button to see
more details
2. If you’re pretty sure a possible duplicate is not the same real
person, click on the Not a Match link and enter a reason
why you believe this is not the same real person.
3. If a person shows up in the “Can’t Be Merged at This Time”
list, a constraint is preventing the merge.

11. Star Ranking Levels
Possible Duplicates Screen
• Shows 3-star and above matches
• Estimate 92% of persons presented are real matches
• Estimate 97.4% of all real matches are being presented
Temple Reservation Check
• Will flag if there are any 4-star and above matches
• Estimate 99% of persons presented are matches
• Estimate 89.5% of all real matches are being presented
• Doesn’t show unmergeable persons (including IOUS)

12. Star Ranking Levels cont.
5-star – Estimate 99.76% are real matches
4-star – Estimate 93.25% are real matches
3-star – Estimate 51.13% are real matches
2-star – Estimate 2.73% are real matches
1-star – Estimate 0.24% are real matches
Saw huge drop in Not a Match declarations
when 2-star matches were eliminated

13. Star Ranking Insider’s Tips
If you really want to see all of the possible duplicates a person has, including those below
3-stars, you can get them by going to the following URL after logging in. Substitute the
person ID of the person you’d like to see the possible duplicates for. You can vary the
matchThreshold if you really want too.
https://familysearch.org/tree-data/match/by-id/{personId}?matchThreshold=1.0
If you want to see more information about how well two persons match, their match score
in both directions (which may be different), merge constraints, and not a match
declarations, enter the following URL after logging in. Substitute the person IDs of the
two persons you are interested in.
https://familysearch.org/tree-data/match/score/{personId1}/{personId2}
** WARNING**
Both of these will give you back data in a “ugly” computer format called JSON. To make
it a bit more human readable, Google for a JSON formatter which you can paste the
result in to make it more readable. The one I usually use is http://jsonviewer.stack.hu/.

14. Top 10 constraints preventing merges
1. Locked relationship
2. Too many inner persons
3. Forwarded person (Usually just merged)
4. Gender mismatch
5. Multiple membership records (CMIS)
6. Other order only – Must preserve membership
7. Merging would cause loop
8. Locked person
9. Non-Unique IDs
10. Parent and child

15. Individuals of Unusual Size (IOUS)
If the resulting record in
new.familysearch.org would have
more than 250 combined records,
persons cannot be merged. This is
sometimes called an Individual of
Unusual Size (IOUS). There isn’t
anything that can be done to merge
these persons until synchronization
with new.familysearch is turned off.

16. Merge Constraint Insider’s Tip
A couple of the merge constraints will give you an indication of what is wrong
with a message. For example,
When you see two persons that cannot be merged and you’re not sure why,
you can get a semi-understandable reason by going to the following URL after
logging in, substituting the person IDs of the persons you want to merge.
https://familysearch.org/ct/persons/{personId1}/merge/{personId2}/constraint

18. Terminology for Persons in Merges
• Surviving person
• Resulting person
• Person merged into
• Left hand side of merge page
• This is the person that will
remain when the merge is
completed and whose data is
changed as specified with data
from the second person in the
merge.
• Duplicate person
• Deleted person
• Archived person
• Person merged away
• Right hand side of merge page
• This person will be deleted (or
archived or tombstoned if you
prefer those terms) during the
merge.
• There will be a pointer or
forwarding ID that points to
person 1 so you will know
where the "real" copy of the
person is, but this second
person will no longer be active
in the system.

21. What is automatically copied
during a merge?
1. Photos
2. Stories
3. Documents
4. Notes
5. Watches
6. Not a match declarations
7. Discussions
8. LDS Temple ordinances
Insider Tip
Use beta.familysearch.org to test hypotheses regarding what
does/doesn’t occur during a merge. There is an out of date copy of data
on production (familysearch.org) there.
Note: Dismissed research suggestions are cleared on the resulting
person after a merge.

22. Merge by ID

23. How to Undo Incorrect Merges

24. Two Ways to Restore After a Merge
1. Unmerge
• Undoes all merge changes, restoring both persons to the pre-
merge state
• Can currently only be done if no changes have taken place on
either person since the merge
• To unmerge, click on the Show All link in the Latest Changes
box to the right of a person who was merged into. Then click
on the Unmerge button and enter a reason for the unmerge.
2. Restore Person
• Restores the person who was deleted to the pre-merge state,
but leaves the merged person alone
• Is only option if changes have taken place since the original
merge
• To restore a person, bring up the deleted person page and
click on the Restore Person link.

30. Merging vs. Combining Undo Rates
Between Mar – Oct 2012
1 in every 4 combines was undone by a separate
Since Nov 2012 (when merge was turned on)
Only 1 in every 30 merges was undone by an
unmerge or restore
Seems to be greatly reducing churn
As of June 2015, ~42,000 merges occur daily

31. Best Practices

32. Merge the person with less data
into the person with more data
• Will result in less changes in the change history
• Copying data from the deleted person won’t
result in many changes attributed to you
• Is more likely to execute quickly and less likely
to have an error because there are fewer
operations being performed

33. Resist the impulse to remove data you
don’t like (during merge and otherwise)
• Completely different alternate names and additional
spouses, parents and children that don’t seem to
belong are usually indicators of an improperly
combined person in new.familysearch.
• Support is no longer performing separates, so trying
to clean up data to represent a single real person is
the best course of action. Making these changes
outside of a merge allows for better documentation
of the reasons for the changes.
• Features are coming to help address LDS temple
ordinances being attached to the correct person.

34. Coming Soon-ish
• Ability to view all of the LDS temple ordinances
attached to a person
• Request that LDS temple ordinances that don’t
belong be moved elsewhere
• Removal of synchronization with new.familysearch –
will allow more merges, including IOUS

35. Copy all data unique to the right hand
side, unless you know it is not correct
• My opinion is that relationships and sources should
always be added (copied) on a merge
• Not copying data will result in it no longer being
active in the tree
• Not bringing relationships over can make holes in
other patron’s trees and reduce the likelihood of true
matches showing in Possible Duplicates.
• I believe if you really don’t want a relationship or
source on the resulting merged person, you should
delete it before or after the merge with its own
justification.

36. Collaborate with other users
• If you see people doing merges that don’t make
sense, help them understand what they did
wrong in a kind way
• Call support if there are problems with “merge
wars”
• Another feature coming really soon is reporting
abuse of data

37. Specific Examples and
Frequently Asked Questions

38. The core question to always ask is:
“Are these two persons the same
real person?”

39. Common Scenarios
1. I see some children belonging to two parents and others
belonging to a single parent with the same ID as one of the
coupled parents
• This is actually not a case for merging
• The first thing to do is make sure all of the correct children
appear under the couple. If any don’t, you need to add a
relationship from the child to both parents.
• Then go and delete the single parent relationships to each child
2. The same spouse, child or parents a person already has
appears on the right on a different line of the merge page
when I’m choosing what to Add/Replace/Reject.
• Make sure you add (copy) the relationship to the merged
person
• This is likely another duplicate that also needs to be merged
3. See Additional References in syllabus for additional scenarios

40. Question
Why can’t you give an indicator as to whether there are any
possible duplicates on a person?
Answer
The call to check for possible duplicates uses a fair amount
of system resources, so we don’t want to do this every time
a person page is opened. We are looking into ways to
speed this up and/or provide better mechanisms to let
patrons know when possible duplicates exist.

41. Question
Should I mark a person as Not a Match if I’m not sure
they are the same person or not?
Answer
It depends. If you’re worried about other people
merging them and want to do more research it may be
a good option, but remember Not a Matches will not
appear as Possible Duplicates.

42. Question
What if I know a person matches, but doesn’t show up
in the possible duplicates list?
Answer
After clicking the Possible Duplicates link from the
person page, click on the Merge by ID tab. Copy the
ID you would like to merge into the text box and
proceed with the merge as usual.

43. Question
What happened if I went through all the steps to merge, clicked
Finish Merge and I get a pink message that these persons can’t
be merged?
Answer
Most likely you have encountered a bug. Please call support to
report it or send an e-mail to bakerb@familysearch.org. The only
legitimate reason this message should appear after initiating a
merge is that it took more than 5 minutes. This is another
constraint of the system that will be resolved when
synchronization with new.familysearch.org is off and merging will
be much quicker.

44. Question
What if I get a pink message after trying to
unmerge or restore a person? Is that an error too?
Answer
Yes, most likely. Please follow the same steps as
listed in the previous question.

45. Question
What happens to LDS temple ordinances during a
merge?
Answer
Any ordinances on the person deleted by the
merge are automatically copied to the resulting
person

46. Question
What happens to photos and stories attached to a
person during a merge?
Answer
Any photos and stories on the person deleted
during the merge will be copied to the resulting
merged person.

47. Question
Why don’t merges show up in the watch list even
though they do show up in the watch e-mails?
Answer
They do now. Significant changes to the watch list
have been made recently to improve the watch list
and changes to people you are watching.

48. Additional References to
Learn More

49. User’s Guide
http://broadcast.lds.org/eLearning/fhd/
Community/en/FamilySearch/FamilyTree
/pdf/familyTreeUserGuide.pdf

50. https://familysearch.org/learningcenter/lesson
/family-tree-curriculum/818

51. https://familysearch.org/treetraining

52. Additional Q & A