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How to Define Source Categories

How to Define Source Categories

Gigatrees supports a number of different options for categorizing your sources. When defined, source categories are shown on the profile page for each source, as well as in the tooltips for every source reference. They are also shown on the sortable source index page.

The purpose of defining source categories is to help determine the possible types of bias that may overshadow the claims the source makes. Source categories are used internally by Gigatrees to help calculate reliability assessments. Gigatrees defines two types of source categories ('concurrency' and 'authority') that may be assigned to your sources. Each category type has several possible values.

Source Concurrency may be set to "primary", "secondary" or "unreliable", where primary represents that the document was created at the time of the recorded events (such as a birth certificate), secondary represents that the document was created some significant amount of time after the events occurred (such as a transcription of a birth certificate), and unreliable is a source that is known to be error prone.

Source Authority may be set to "dna", "original", "transcript", "copy", "abstract", "research", "memoir", "derivative" or "unknown". When adding a source containing yDNA or mtDNA test results that prove a biological relationship, the dna category should be used. It would be inappropriate to use this for autosomal DNA test results unless those results were combined with an in-depth analysis showing why they could be used as proof. original represents a document in its original form (such as a birth certificate). transcript is a direct unaltered transcription of an original source. copy is a subsequent copy of a transcription or of another copy (i.e. copy of a copy). abstract is any abstraction or summary of the original source (not in its original form). research is an authoritative collection of claims derived from multiple sources. In order for the collection to be considered authoritative, the researcher or genealogist should have included the relevant source citations. memoir is a collection of authoritative claims taken from memory, such as an autobiography, letters, notes, etc. derivative is a non-authoritative collection of claims derived from multiple primary and secondary sources. This will include most books, town histories, etc. unknown is a source from which no information as to its authority can be determined.

The source category strings are translatable so that you can use strings in your own language.

Claims that are both primary and original are generally considered to be unbiased, though not necessarily without error. Secondary sources may suffer memory bias due to a time lapse occurring between the event and the recording as well as from copy errors. Derivative sources may also suffer from these as well as author bias, intentional or otherwise. All sources may contain lies.

From experience we know that certain types of records are more accurate and have less bias than others. For instance, birth certificates (original, primary) almost never have incorrect birth dates. Baptism records (original, secondary), even those recorded within just a few months of birth, may contain incorrect birth dates caused by memory lapses of the mother, as astounding as that seems. Death certificates and tombstones (original, secondary), which usually occur many years after birth and the informant is generally not the mother, often contain incorrect birth dates. Census records (original, primary) are notorious for having inaccurate ages due to the fact that the informant was more than likely a spouse of the head of household, and who, especially early on, had little formal education resulting in subtraction errors or simply guesswork. Had the census authorities required birth years instead of ages, they would probably be much more accurate. Census records, however, are very accurate for documenting parental relationships, so there you go.

Categorizing sources can be very tricky and is sometimes more art than it is science. Gigatrees therefore allows you to not only categorize your sources, but to also override the reliability assessments derived from those categories for individual claims when necessary.

For many sources, multiple source categories might apply. When determining the appropriate source category to use, you should choose the least authoritative category that applies to the claims being extracted from it. For instance, if you have a source that includes scans of original documents, along with some memoirs and derivatives, but you are only using the images of the original documents from that source, they you can rightfully choose original as your source category. If however you include claims from the other areas of the source, then you should choose a different source category. A serious genealogist might, in this case, split their single source up into several source entries, each with their own category.

Gigatrees supports RootsMagic method for adding source categories as part of a source reference. RootsMagic only supports source categories that align with those defined as part of the Genealogy Proof Standard, and then uses only the capitalized first letter of the category. For instance, in the following example, "O" is an abbreviation for original and "P" is an abbreviation for primary. Gigatrees will use the first reference it finds for a source to define the source's category, and ignore all other categories defined in all other source references to the same source. It is assumed that they are all identical.

0 @I1@ INDI
1 BIRT
2 DATE 7 FEB 2014
2 SOUR @S1@
3 _QUAL
4 _SOUR O
4 _INFO P

Most genealogy editors do not allow adding user defined GEDCOM tags to their sources, so the easiest way to add source categories is to use Gigatrees' application interface and the Source Citations option. Doing so has several advantages. No editing of your GEDCOM file is necessary, and once you have added a category, it is saved into your configuration file, so you will not need to re-add it when you modify your GEDCOM file or re-export it. You will need to add a category every time you add a new source, but it is a relatively easy process and well worth the effort. To determine which of your sources are missing categories, go to your source index page, and sort it by category.

"Source Citations Option Page (top)"
Using Source Citations Option

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