Feb 062012

Prior to leaving for RootsTech 2012, I indicated that I would not be blogging during the conference, but would begin to put my learning to work and report on the results.  My first after-RootsTech post is about a newly developed numbering system for genealogical purposes.

My son and I have discussed for a long time the possibilities of a numbering system for our genealogical records.  The most prominent systems available to us as genealogists is, of course, derive from the Ahnentafel system which dates back to Michael Eytzinger in 1590.  I recently spend time looking at William Dollarhide’s combination of the Ahnentafel and Henry systems — in particular, Terry Cole’s adaptations of Dollarhide.  In truth, none of the systems we discussed, “invented,” or tried out seemed to be what we had hoped for.  A RootsTech workshop on the Ancestral Lines Paring System, attended by my son, has changed that.

The Ancestral Lines Paring System was presented by Capers W. McDonald its developer.  NEHGS has published McDonald’s paper which describes the  Ancestral Lines Paring System.  More information about the system can be found at the Ancestral Lines website.  This system differs significantly from Ahnentafel.   The Ahnentafel system begins with the root person in your pedigree and counts that person’s ancestor’s in numerical order, moving backwards through the generations.  The Ahnentafel system is based on simple arithmetic progression. It is designed to be an index number, a locator.  It contains no genealogical content — that is, each Ahnentafel number is simply a pointer to a particular individual in your pedigree.  By itself, it does not convey information about a person’s ancestral line or generation.

Each Ancestral Lines Paring System two digit number, on the other hand, indicates precisely the ancestral line and the generation to which the individual belongs.  I found the concept of Ancestral Lines Paring System intuitively to be quite clear.  Each direct ancestor’s number is a combination of the ancestral line and the generation.  1.7, for example,  represents the 7th generation direct paternal ancestor of the root person in the pedigree.  In our case, since we have my son listed as the root person, 1.7 is Georg Friederich Brenner (my son’s 4g-grandfather).   The full implementation of the Ancestral Lines Paring System , on the other hand, took a bit more than intuition.  Yesterday, with some patient coaching by my son, I was able to identify the Ancestral Lines Paring System number for all direct ancestors in our newly pruned data base.  (Recently I pruned a 7000 individual RootsMagic 5 database down to 700 persons.  I removed many, many unsourced people and a ton of collateral lines.)

The root person (female or male) establishes ancestral line #1.  They are also the 1st generation, so their Ancestral Lines Paring System number is 1.1 — the first is the line; the second, the generation.  All their direct line paternal ancestors are line #1, but a different generation.  Dad Brenner is 1.2 (1st line, 2nd generation); Grandpa Brenner is 1.3; Great-Granddad Brenner is 1.4; and so forth.

The root person’s mother (Mom Brenner) establishes the second ancestral line in the pedigree and is numbered 2.2 (2nd line, 2nd generation).  Note Mom Brenner (nee Weaver) is second generation relative to the root person.  Each direct ancestor at the same level in your pedigree tree will have the same generation number, but a different line number.

Grandpa Brenner (Dad’s Dad) is 1.3 as noted above — ancestral line #1, 3rd generation.  Grandma Brenner (nee Deeter), the same generation number as Grandpa, establishes a new line, the third one so far.  Her number is 3.3 — ancestral line #3, 3rd generation.  Mom’s Dad, Granddad Weaver, is 2.3 (remember, Mom Brenner established ancestral line #2) — ancestral line #2, 3rd generation.  Mom’s Mother (don’t call her “Mom”), Grandmother Weaver (nee Gregg), establishes the 4th ancestral line, so she is numbered 4.3

As we continue to add maternal lines, their number is determined by a mathematical formula (see Capers McDonald’s paper).  Here are the basic concepts involved:

  1. Generation #2 contains two people – the father and mother of the root person.
  2. Once established, ancestral line numbers persist as you continue to expand your pedigree; generation numbers change.
  3. All ancestral lines extending back from the root person’s father (line #1) will be odd numbers (3, 5, 7, 9, etc.).
  4. All ancestral lines extending back from the root person’s mother (line #2) will be even numbers (4, 6, 8, 10, etc.).
  5. Each new ancestral line added will be a maternal line — odd number, if the lineage is from the root person’s father;  even number, if from the root person’s mother.
  6. As each new ancestral line continues, it is treated as a paternal line — that is, the line # persists, the generation number increases by one for each new generation.   Even though each ancestral  line begins with a mother, it continues through her father / grandfather / great-grandfather / etc.
  7. The computation of each new maternal line is as follows:  take the ancestral line number of the woman’s husband (that is, the ancestral line into which she marries) and increase it by the total number of possible direct ancestors in the previous generation.   (McDonald provides a formula because the actual number of possible direct ancestors in each generation increases exponentially – 1, 2, 4, 8, 16, 32, 64, etc.)
The Ancestral Lines Paring System  can be expanded (three-number format) to include siblings of direct ancestors or, alternately, a four number format can be used to identify all siblings plus half-siblings.  At the present time, we have chosen to use the simple format and will perhaps move to the three or four number format in the future.
I have entered the Ancestral Lines Paring System reference numbers into our RootsMagic 5 database (as “Reference Numbers”) and have transferred that data to our TNG website.  As we redevelop the website (coming soon), my son hopes to add code that will have all outputs display the  Ancestral Lines Paring System numbers.  My next step is to add the Ancestral Lines Paring System numbers to our organizational filing system (our private Research Wiki).
Conceptually and visually, the Ancestral Lines Pairing System is quite clear and simple; and it adds content information to each individual’s identifying number.  Computationally, it can be somewhat more complex.  Once the computational method is understood, however, the addition of Ancestral Lines Paring System numbers is very straight-forward,.  I commend Capers McDonald on his work.  He has done a great service to genealogists.  I look forward to the increasing adoption of the Ancestral Lines Paring System and, eventually, its inclusion in genealogical software and online systems.

  3 Responses to “RootsTech Learning #1 — Ancestral Lines Pairing System”

  1. Bart:

    This is an excellent article you wrote describing this system.

    But radical-me just has to pop in and express my disdain for any numbering system. They only work with static trees. Change the starting person and the numberings change. In some system, you add a new-found person and often much has to be renumbered.

    The whole worth of any numbering system to me is overblown. It is just a dewey-decimal-like number, to enable you to find the person you want in your tree as quickly and easily as possible. The system that enables someone to do this the most easily is the best for them.

    Thus to me, simplicity in numbering systems always wins over complexity.


  2. Brenners Both,

    I am delighted to have met you at RootsTech 2012 and now learn that you are "implementing" the Ancestral Lines system! Hope it helps, especially in your wide-ranging communications.

    One postscript: In preparing for publication, I solicited ideas for "naming" from several experienced resources, including among both companies and users in our genealogical community. The "ALPS" acronym surfaced, but the more descriptive "Ancestral Lines" was preferred, since clearer communications is one of the principal goals, and this one most clearly indicates that the system is "ancestral" (not descendant) and visibly indicates "lines" (as its first number). Even though "ALPS" is shorter and reasonably easy to recall, in addition to other attributes, "Ancestral Lines" happens to have the same number of syllables as the time-honored, "Ahnentafel." Hope this eventually may be of some (historical) interest!

    Capers McDonald
    Author, Ancestral Lines Pairing System

  3. @Capers, I used the ALPSys acronym for brevity in the post. After reading your explanation, I have edited the post and removed "APLSys" so that the full name appears throughout.

    @Louis, when I pull my GEDCOM into your GEDCOM reader, Behold, and look at the opening screen of the Everything Report, I would dearly love to see a two digit indexing number that would indicate the ancestral line and generation for each entry. Unless I know a particular direct ancestor in my GEDCOM, I do not necessarily know where they belong in the pedigree. Likewise, in a more traditional pedigree display (RootsMagic 5, for example), I would appreciate seeing the two digit ancestral line and generation numbers for the entries, especially when I have gone deep into the pedigree tree. I am all for any system that helps me better understand the work I am doing.

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