Genealogists often adopt a numbering system to keep everyone straight in their database. Numbering Systems abound, but few allow the numbering of all people in a database. Some are good for numbering ancestors, while others are more adapted for numbering descendants. Few systems deal with collateral people in the family tree such as in-laws, unrelated marriages, etc. William Dollarhide proposed a system that seems to marry the strengths of a number of systems. His work and thoughts are documented at the Genealogy Bulletin archive site. Terry Cole has proposed some modifications that are useful with computer programs and genealogy databases.
First, a person is selected as the starting point. All people in the database related in any way to this person can be numbered using this system. The starting person is person 1.
Using traditional Ahnentafel or ancestry numbering, the starting person's father is person 2, his/her mother is person 3, paternal grandfather... person 4, paternal grandmother ...person 5, etc. Each person's father is double his/her own number; each person's mother is double plus 1. Dollarhide prescribes adding a decimal point (.) and zero (0) to the Ahnentafel number. All direct ancestors have a number that ends in ".0", making it very easy to identify direct ancestors from a list.
Below is a simple chart of ancestor numberings.
|Paternal grandfather 4.0|
|Paternal grandmother 5.0|
|Starting Person 1.0|
|Maternal grandfather 6.0|
|Maternal grandmother 7.0|
Dollarhide prescribes that siblings and half-siblings of ancestors are numbered using a decimal (.1, .2, .3, .4, etc.) suffix, similar to the Henry numbering system. Thus all the (half-)siblings of person 3.0 are labeled 3.1, 3.2, 3.3, 3.4, etc. They are numbered in birth order (or whatever the genealogist believes is the best order when birth order is not available). An ancestor's number ends with a '0' rather than his/her birth order, making it stand out from the siblings' numbers. This allows one to see the birth order of the direct ancestor at a glance. For example, if one's grandfather has two siblings, one older and one younger, the three of them are numbered 4.1, 4.0, and 4.3. One can easily see from the numbers that there are three siblings, and infer their birth order (or the selected listing order) of each. The entire set of siblings, including half siblings through each direct ancestor parent, receives numbers that have the person number of the ancestor. This makes it easy to identify these extended families.
It is not uncommon to run out of numbers. In this case, letters (.A, .B, .C, .D, etc.) are used.
Below is a table showing an extended family that includes half siblings.
|Family of 25.0 with first husband.||Half sister 12.1|
|Direct Ancestors 24.0 & 25.0 Family||Older brother 12.2
Older sister 12.3
Direct Ancestor 12.0
Younger brother 12.5
|Family of 24.0 with second wife.||Half brother 12.6|
You will note in the above example for direct ancestors that there are no numbers for the spouses. Dollarhide denotes a collateral spouse by a * (or $) suffix on the spouse's number. If there is more than one marriage, *1, *2, *3, etc. are used, in order of the marriage (or whatever order the genealogist thinks best if this is not available). This spouse ID scheme applies to any marriage not of two ancestors. Thus spouses of siblings can be numbered (12.1*) or previous or subsequent spouses of ancestors. As in the case for numbering siblings, the marriage number corresponding to a marriage of the two ancestors is skipped. Spouses of descendants are numbered the same way.
|25.0*1 married to 25.0 (divorced or widowed)|
|24.0 married to 25.0 (divorced or widowed)|
|24.0 married to 24.0*2|
Dollarhide prescribed numbering descendant,s as well as ancestors. Descendants are numbered by appending a new number to their already numbered parent. This again is much like the Henry numbering system. Thus, descendants of the starting person become 1.01, 1.02, 1.03, etc. (The '.0' of the starting person's number is retained as a descendant's birth order is appended.) This is applied as often as needed, so grandchildren of the starting person are 1.011, 1.012, 1.013 (children of 1.01) and 1.021, 1.022, 1.023 (children of 1.02), and so forth.
Descendants of a sibling (say 9.1) of ancestor 9.0 would be numbered 9.11, 9.12, 9.13, etc. Note that some cousins have a nice property in that they have similar numbers using their common ancestor.
Below are some examples of how to decipher the numbers.
|1.0||The root person.|
|1.A||The 10th birth order sibling (or half sibling) of the root person. (If this is the last sibling in the list, we know there are 10 children.)|
|3.0||The mother of the root person. (The father would be 2.0)|
|3.3||The third birth order sibling of the mother of the root person.|
|4.12||The 4 tells us that the person is related to the root person's paternal grandfather (who is 4.0). The ".1" says there is a first birth order sibling of the grandfather. And the last 2 tells us the person is the second child of this person.|
|6.0*1||The 6.0 tells us the person is related to the root person's great-grandfather. The *1 identifies them as the first spouse of this great-grandfather, and otherwise unrelated to the root person. (The related great-grandmother is number 7.0.)|
Using the methods above, it is possible to number all ancestors and spouses going backward. Additionally it is possible to go forward from any of the direct ancestors. This allows one to number many of the common people in our databases. But what of mothers-in-law? Brothers and sisters of in-laws? Or even their descendants?
Dollarhide's system allows one to go backward in the family line (2.0 to 4.0), to go laterally in a family (4.1, 4.2, 4.3) and to start going down the family tree again (4.31, 4.32, 4.33). This change in direction from backward to forward seems fairly natural. Dollarhide says that we can change direction in another way. He uses a colon (:) to signal the start of a new pedigree of a person who is not an ancestor of the root person. [Cole uses a slash (/) rather than a colon.] To go backward from a spouse labeled person 9.2*1, his or her father can be numbered 9.2*1:2.0. Everything on the left of the ":" is treated as person 1 of the new pedigree, and moving backward. 9.2*1:3.0 is the mother of 9.2*1. The tree can continue backward and forward again using descendant numbering. This change of direction can be applied at any level. One might think of it as a small tree that grows within the larger tree.
Sometimes you just don't know the birth or marriage orders. In such cases, Cole has suggested using a series like x, y, z (or other "late alphabet" letters). This signals that one doesn't know, and encourages one to research to find out for sure. It allows one to number additional relatives on the basis of the temporary number. Of course, if this gets out of hand it may not be very useful. If it remains a long-term assignment, it is probably best to simply number the item with a best available guess and move forward.
Multiple Starting Persons
A situation for multiple roots is the goal of giving equal status to all of a set of siblings, rather that just one being the root person (1.0). This can be done by designating all siblings as 1.x. For example, 1.1, 1.2, and 1.3 (none ending with '.0') for three brothers or sisters who will each be treated equally as a root person. If these children do not have the same parents, one set of parents is selected for the direct line, and the other parents are labeled using secondary spouse designators.
Multiple roots can also help with a computer limitation when dealing with these labels. The further back one goes, the longer the labels get. Some computer databases have a limited number of characters available for custom identification or numbering. One can designate a new root to truncate an extremely deep ancestry numbering. When one reaches the limit, one must designate a new root. This shortens the numbers again so they fit within the software limits.
Using the Labels
It is possible to denote more than one starting point. One might want to do this for several reasons. First, it might be desired to describe more than one set of people for whom no relationship can be exactly described (because they are related, or because the relationship cannot yet be described). In this case, they can be designated person one (1.0) but with a unique prefix for each. For example, person 1 to your main tree, but person Z1 for a set of related people for whom one intends to eventually find a precise relation. Or two equally important trees could be described with designations A1 and B1 for root people. When people are related in some way to both root persons, one must choose between two possible labels or renumber everyone as one or the other trees (using the common person as the starting point).
These numbers must be assigned and entered by hand (unless you have a computer program to do it for you) into a customizable identification field. Some programs can display this number alongside names on the computer screen and in reports.
The identification numbers are very useful for numbering computer files, label reports (e.g., 12.0 Individual Full Name.pdf, 12.0 & 13.0 Family Group Full Names.pdf, 12.0 Pedigree Full Name.pdf, etc), picture files (12.0 Name (date) Place.jpg), and sources (15.0 Birth Certificate Name Issuer), etc. Because one cannot use the * character in the file name or the separator (:) in many operating systems, one has to devise a substitute. As an example, Dollarhide suggested using $ in place of *. Cole has recommended other options. Dollarhide has indicated that any symbol may be used and it would still be “Dollarhide Numbering”.
These labels, when used to prefix computer files, give automatic grouping by person and family groups.