Monday, 23 July 2012

Lineage societies and the genealogical proof standard

Since the end of the 20th century the genealogical proof standard (GPS) has been the benchmark for US professional genealogical practice, accepted and actively promoted by the Board for Certification of Genealogists (BCG). But there has been little penetration of the GPS elsewhere as evidenced by the very few members of BCG outside the US. There are seven Canadian members and a few strays, one each in France, Germany, Ireland, and New Zealand. Why?

One factor might be the nature of the market outside the US, and to some extent Canada, and the opportunity that exists there in helping people to become a member of a lineage society. For example, the Daughters of the American Revolution (DAR), has 168,000 members. It's open to "any woman 18 years or older who can prove lineal, bloodline descent from an ancestor who aided in achieving American independence... She must provide documentation for each statement of birth, marriage and death, as well as of the Revolutionary War service of her Patriot ancestor." There's more detail on their genealogical requirements at http://www.dar.org/natsociety/content.cfm?ID=95&hd=n&FO=Y

In Canada the Ontario Genealogical Society operates four Heritage Societies:
War of 1812 Society; Centenary Club; The 1837 Rebellion Society and; Upper Canada Society. I'm not aware these are particularly active. More successful, and of much longer standing, is the United Empire Loyalists' Association of Canada.

The genealogical proof standard has been embraced as a basis for determining whether a case made meets a professional standard, one that would be accepted by a lineage society.

Such societies either accept the case and grant membership, or don't. Just as in a court of law it's guilty or not guilty.

A genealogical proof is never complete. New evidence is always liable to appear. For example, DNA evidence suggests that 1 - 5% of children are not born to the supposed father.

What that means is that, using a 2% non-paternity rate and six generations between the American revolutionary and the living descendant, likely 10% of DAR members are not  the revolutionary era descendant they're supposed to be. That's more than 16,000 DAR members.

If you read explanations of the genealogical proof standard you will encounter frequent mention of probability. For example, Elizabeth Mills in http://learn.ancestry.com/LearnMore/Article.aspx?id=803 writes "No matter how carefully studied the problem may be, the case is never closed in genealogy. It is simply impossible, from the study of historical evidence, to prove parentage, identity, or origins beyond any margin of error. The most we can do is to establish probability through an expert analysis of the evidence known to date."

Were it not for lineage societies as a driver for genealogical research, and their requirement to either accept or reject an application, the US genealogical profession would likely be much more amenable to adopting a probabilistic approach to the presentation of research results.

7 comments:

James Tanner said...

Very interesting observations. Thanks for the post.

Randy Seaver said...

Interesting post. I'm unclear as to your meaning of "probabilistic approach." How would that work?

The DAR requires actual paper proofs (a birth record, a marriage record, death record,or some other original source record) rather than a circumstantial case that might be found in NGSQ or a BCG application.

Malcolm said...

Genealogy research is becoming more sophisticated and employing more techniques which lead us into some more esoteric areas where a more traditional introduction through a planned educational program would provide the necessary background. Copyright is one of these, and statistics is (definitely) another.

One of the first principles of statistics is that it actually applies to almost all of the things we think of as "This" or "That," with no room for compromise between them. From a statistical point of view its actually "a x% probability of This" or "a y% probability of That."

These statistically more correct statements, however, make conversations more complicated (and your head hurt!) so the "This" or "That" definitions are acceptable in most instances, and are taken as including some possibility of error (by most reasonable people.)

So, to finally get to the point, there is no real conflict between "certifying" someone's heritage - for some practical purpose - and making the more confusing, complex, statistically correct statement of "This with a probability of X% so many times out of whatever."

Its NOT an either / or - its statistical! :)

M. Diane Rogers said...

Like Randy, I'm unclear about your meaning here - and about your particular idea of the Genealogical Proof Standard (GPS) and its use, which doesn't seem to me to be associated in particular with lineage societies. And, I think it important to note that the use of the Genealogical Proof Standard is not limited to only those who've achieved BCG certification, nor does use of the GPS result in an absolute or 'forever' answer to a genealogical query. Quite the contrary, in my view. And the very lively discussions on message lists like that of the Association of Professional Genealogists and on many blogs attest to that.

Alison Hare said...

Diane's quite correct in her observations. GPS conclusions are not hard and fast, as this post seems to imply. If new evidence surfaces, the conclusion should be revisited. There's also nothing anywhere that prohibits qualifying a GPS conclusion as less than 100 per cent certain. Indeed, a researcher would be remiss if he or she did not appropriately qualify a conclusion as probable or likely or possible, depending on the strength of the evidence. To suggest use of the GPS is being driven by lineage societies or their needs is also untrue. Many societies don't even consider it. Finally, the number of BCG associates in various countries is a poor indicator of GPS acceptance in those countries. There are numerous reasons that may influence an individual's decision to pursue certification and even in the U.S. many people support the GPS without ever seeking certification.

Alison Hare, CG
BCG trustee

JDR said...

Thanks to all who posted comments. I'll try and elaborate on the probabilistic approach in a separate blog post.

In discussing lineage societies I mentioned their strength in the US as one factor, not the only factor, behind why professional genealogy has flourished there. While there must be other factors surely lineage research puts bread on the table for some professional genealogists.
What are the other factors and what is their relative significance that would account for the lack of adoption of the GPS elsewhere?
If the lineage society requirement is not a factor why does BCG seem tied to the guilty/not guilty system rather than accepting there there is a whole range of probabilities that conclusions drawn from evidence might be the truth?

Nowhere did the post claim there was a 100% threshold implicit in the GPS. I don't know how more strongly that could be put than in the post "A genealogical proof is never complete. New evidence is always liable to appear." The point is that some as yet undefined, and likely variable, level of probability, less than 100%, is implicitly being adopted when the judgement is made a proof meets the GPS. What is it? Would it have to be more certain than 51% which would be POE?

Elizabeth Shown Mills said...

Hi, John,

Interesting post—as most of yours are—and it is especially good to see non-U.S. perspectives on genealogical standards. But I may be up all night mulling your last paragraph and your follow-up comment at 21:11!

Your last paragraph stated: “Were it not for lineage societies as a driver for genealogical research, and their requirement to either accept or reject an application, the US genealogical profession would likely be much more amenable to adopting a probabilistic approach to the presentation of research results.”

As a U.S. genealogical professional (and a Board-certified genealogist) for 36 years, I would argue vociferously that (a) the GPS does take a “probabilistic approach to the presentation of research results”; and (b) lineage society requirements have not been a strong driver of standards during my professional life. The drivers for the last 25 years at least have been BCG, NGSQ, and APG.

Your follow-up comment also asked: “Why does BCG seem tied to the guilty/not guilty system rather than accepting [that] there is a whole range of probabilities that conclusions drawn from evidence might be the truth.”

I’m mystified here, John. In 36 years of association with BCG, I have never known it to propose any “guilty/not guilty system.” In Evidence Explained, as a BCG trustee and former president, I wrote:

“For history researchers, there is no such thing as proof that can never be rebutted. … Every conclusion we reach about circumstances, events, identities, or kinships is simply a decision we base upon the weight of the evidence we have assembled. Our challenge is to accumulate the best information possible and to train ourselves to skillfully analyze and interpret what it has to say.” (EE 1.3, “Conclusions: Hypothesis, Theory & Proof,” also at https://www.evidenceexplained.com/sites/default/files/documents/1.3.pdf ).

This is BCG’s stance. In fact, BCG officers vetted the book before it went to press and it is one of BCG’s recommended research guides—along with Brenda Merriman’s excellent book on genealogical evidence. In fact, this passage goes on to say, quite explicitly:

“A conclusion cannot always be reached. When the accumulated materials are appropriately appraised, the evidence may or may not support a decision. If it does not, then the question remains open … until sufficient evidence is developed. If extenuating circumstances pressure for a decision (as with, perhaps, impending court testimony in a dispute over historical property or heirship), then the researcher is obligated to present all relevant evidence, interpreted accurately, and to appropriately qualify whatever hypothesis seems warranted. This is commonly done through the use of terms that denote levels of confidence.”

If those words are strong enough, let me quote EE 1.18, in the section called “Problematic Concepts.”

“1.18 ‘Final Conclusions’
“The case is never closed on a historical conclusion. Just as scientists revise their theories in the wake of new discoveries, so do historians. Any decision we make today could be changed tomorrow by the discovery of previously unknown information.”

The GPS does, indeed, deal in probabilities. It lays out 5 standards—5 work-practices—that help us reach more-reliable probabilities; but every conclusion we reach is a probability.

Elizabeth Shown Mills, CG, CGL, FASG
www.Facebook.com/EvidenceExplained