Ethnographic decision models
(EDMs) predict how people behave under specific circumstances. EDMs often take
the form of tree diagrams or charts listing different choices that people make.
Click the example of an EDM
on the topic “Whether students
attend an Adult English as a Second Language (ESL) class or not.”
Process
When anthropologists build EDMs, they ask people questions and find logical rules that direct people’s
behavior. This exhibit shows the process of making an EDM using the above
picture.
Think of possible alternatives
within a topic under study. In this example, the topic is “to attend adult ESL
class or not.” The simplest alternatives are “yes” and “no.”
Ask ESL students, “Did you
attend class today?” When they answer, ask them the reason why they came or
did not come to class.
Try to get various types of
decisions, reasons, and constraints from students. When finished getting new
information, build a model that includes at least 80% of all answers given by
students. Try to keep the model simple with the fewest numbers of rules.
Confirm the validity of the
model by testing it on a new sample of students. Ask them all the questions
contained with
the model. Being able to predict whether they attended class from their
answers will demonstrate whether or not the models works.
Well-developed EDMs may lead
to correct predictions with 80-90% accuracy rates (Bernard 2002: 490). EDMs are useful in predicting
people’s behavior in order to create effective policies. According to Bernard
(2002: 490), studies using EDMs have included: how fishermen decide where to
fish (Gatewood 1983), what price to place on their products (Gladwin 1971; Quinn
1978), and how people decide on which treatment to use for an illness (Young and
Garro 1994 [1981]).
Sources:
Bernard, Russell H. 2002 Research Methods in Anthropology:
Qualitative and Quantitative Methods. Walnut Creek: AltaMira Press.
Gatewood, J.B. 1983 Deciding Where to Fish: The
Skipper’s Dilemma in Southeast Alaska’s Salmon Seining. Coastal Zone
Management Journal 10:347-67.
Gladwin, H. 1971 Decision Making in the Cape
Coast (Fante) Fishing and Fish Marketing System. Ph.d. dissertation, Stanford
University.
Quinn, N. 1978 Do Mfantse Fish Sellers
Estimate Probabilities in Their Heads? American Ethnologist 5:206-26.
Young, James Clay, and Linda C. Garro 1994 [1981] Medical Choice in a
Mexican Village. Prospect Heights: Waveland.
This page was created by a
Minnesota State University, Mankato student. Last updated
11/14/04.