What is STEMMA, in a nutshell?
A private research project for representing
micro-history in a transportable fashion (i.e. non-binary, defined schema,
locale-independent, and culture-neutral). The goal is more than that of a simple
exchange mechanism, or even a representation for long-term preservation; it will
serve to create "live" micro-history documents that can be exchanged, opened,
and immediately visualised or navigated.
What is micro-history?
Micro-history is a pursuit that looks at the events
and interconnections in the fine-grained history of subjects that includes
people, places, groups (e.g. regiments, organisations, families), and animals.
This is certainly more than 'family trees' as it is a superset of family
history, local history, and one-name or one-place studies.
Is STEMMA a data model or a data
STEMMA is primarily a data model, which means it is
concerned with the relationships between different aspects of the data,
including micro-history subjects such as persons, places, groups, and animals;
hierarchies, such as lineage; events and timelines; geography; information,
evidence, and analysis; text and audio transcription; and general marked-up
narrative. There is an XML serialisation format defined on this site, but it is
comparatively loose, and not the only possible representation -- the current XML
was designed to be as simple to implement and modify as possible during
Is the informational sub-model
STEMMA has notional sub-models termed conclusional
and informational. The majority of the research work has gone into utilising the
conclusional in conjunction with marked-up narrative. There are aspects of the
informational model that have barely been touched so far, and which would need
very specialised software. See Our Days of Future Passed — Part III.
Is STEMMA lineage-linked?
STEMMA is a multi-linked model. Family lineage is
represented by hierarchies between people, but hierarchies are also used for
place/group relationships, and animal lineage. The popular notion of family
trees is just one potential visualisation of STEMMA data.
Is there a STEMMA Product?
There is no product available. The research project
involves much prototyping of software algorithms and interfaces, and these are
used to encode private data, but they do not form a coherent product of
Does STEMMA require a database?
STEMMA is designed to be loaded quickly into a
memory and indexed there. Disk-based databases, such as relational ones, are not
essential for private data, and cause many problems. See Do Genealogists Really Need a Database.
How is STEMMA related to FHISO?
It is not -- I just happened to be a member of
FHISO too. On a more
a) STEMMA is a private research project associated
with the representation of micro-history. It is not interested in compatibility
with other models. FHISO is currently about
standards for sharing existing genealogical data (generally lineage-linked)
without loss between compliant products. Its community-driven standards will be
freely accessible to the public.
b) STEMMA is more about modelling (getting the data
organisation correct), and less about the serialisation (i.e. file format). It
currently uses a loose XML-based serialisation, but this is deliberately insular
to allow unhindered evolution of the model. FHISO
is heavily focused on serialisation issues that can be applied to several
existing formats. It is adopting very modern concepts that are already part of
the Semantic Web design. It is not currently focused on modelling issues beyond
the capabilities of existing software.
c) Both projects
want an international and extensible method of
sharing and long-term preservation. Neither mandate the use of a database .