#24 redefining study_objects

[Ryan Brinkman]

Currently study_object has 3 siblings

study_organism "e.g. whole individual, mouse, human etc"

study_population "e.g. yeast culture, group of
Icelandic fishermen."

study_sample "e.g. liver from a person (in this case
the details of the individual are characteristics of
the study sample) , water taken from a pond."

study_population should really be study_sample (unless
you have ground up every last Icelandic fisherman on
the planet) and study_sample should be study_specimen,
each defined as follows

study_specimen "A study_specimen is a study_object that
is a portion or quantity of material (e.g., a blood
specimen) or an individual item typical of a group,
class or whole (e.g., a fish in a lake) analyzed as
part of an investigation

study_sample "A study_sample is a study_object that is
a pooled collection of specimens drawn from a
population and analyzed as part of an investigation to
estimate the characteristics of that population"

The distinction is made as "sample" is an overloaded
term representing both something you stick in a tube in
a experimental sense (e.g., a bloos sample) and defined
in the statistical sense (sample vs. population). Since
I don't know of any other good words to descibe "groups
of things drawn from a population", I have used sample
in that sense, leaving specimen to be used to describe
things that are ground up or put under microscopes

I'm not sure of the utility of having both
study_organism and study_specimen as study_specimen
could have properties (e.g., the species of the
specimen) which describes it, which seems to be the
purpose of the term the original definition alludes to.

[Joseph White]

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I think the term 'study_population' is still useful.
Statistically speaking, one is always evaluating at a
sample. But it is often useful to know the source
population, eg geographic or ethnic. So I argue that we
should keep study_population; definition: the source
population being study, as defined by geographic location,
race or ethnicity, etc.

Joe W.

[JenFostel]

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I concur with Ryan's comments.
In the CEBS world, a specimen is defined as any biological
material removed from a Subject and preserved for subsequent
analysis.

[Ryan Brinkman]

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Adding in study_population, this section should then likely
look like

-study_object
--study_population
---study_sample_population
----pooled_study_specimen
----study_specimen

The following new definitions need to be added as well

a study_population is the group of study_objects with a
particular set of characteristics to which researchers
attempt to generalize their findings from a smaller
study_sample_population.

A study_sample_population is a set of study_objects drawn
from a study_population that is analyzed to estimate the
characteristics of the study_population.

A pooled_study_specimen is a set of study_specimens which
have been individually taken from the
study_sample_population, mixed together, and then analyzed
as part of an investigation to estimate the characteristics
of the study_population

The following was previsouly proposed, and still seems to fit

A study_specimen is a study_object that
is a portion or quantity of material (e.g., a blood
specimen) or an individual item typical of a group,
class or whole (e.g., a fish in a lake) analyzed as
part of an investigation to estimate the characteristics of
the study_population