Situated actions as ...

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An alternative view of human action


An alternative account of the relation

of plans to situated actions


The user as a resourceful person

Situated actions as ...


Lucy Suchman, 1987


Anthropologist
,


Philosophy ( Dreyfus)


Phenomenology (Merleau
-

Ponty )


Symbolic Interactionism (Garfinkel, Goffman)



Interested in producing an adequate base of
descriptions of human practices



What’s happens when someone does something ?

Suchman’s central concern



The relation between
observable behaviour

and the
processes not available to direct observation
, that make
behaviour meaningful,



What constitutes purposeful actions and how is it
understood ?

About the European and

the Trukese navigator


The
European

navigator exemplifies the
cognitive science

model of purposeful action


The
Trukese

navigator exemplifies the
situated action

perspective



The view of action exemplified by the European navigator is
being reified in the design of intelligent machines


The logical form of plans makes them attractive for the
purpose of constructing a computational model of action



The view that purposeful action is determined by plans, is
deeply rooted in the Western human sciences as the correct
model of the rational actor





Two alternative views of action

i)
The
planning view


The organization and significance of human action is
located in underlying plans (artificial intelligence)


ii) The
situated actions

view


The prescriptive significance of intentions for situated
actions is inherently vague (ethnomethodology)

The
planning view



Plans are prerequisite to and prescribe actions at every
level of detail


Mutual intelligibility is a matter of reciprocal
recognizability of our plans


The planning view has to do with :


The planning model (Miller, Galanter and Pribram, 1960)


Speech act theory (Searle, 1969 )


The idea of shared background knowledge as the common
resource that is given (Durkheim, 1938)

.


Plans

are a sequence of actions designed to
accomplish a preconceived end,


Action

is a form of problem solving and are
described in terms of preconditions and their
consequences,


Goals

define the actor’s relationship to the
situation of action,


The
situation

is those conditions that obstruct or
advance the actor’s progress toward his/her goal

The
planning model

in cognitive science

Searle’s speech act theory :

some initial guidelines for

computational models of communication


The hypothesis is that people maintain as part of
their models of the world, symbolic descriptions
of the world models of the people



Speech act are regarded as actions whose effects
are primarily on the models that speakers and
hearers maintain of each other

Background knowledge


Gumperz shows that an action significance seems
to lie as much in what it presupposes and implies
about its situation


He questions the view that background
assumptions are part of the actor’s mental state
prior of action


The background knowledge is not taken for
granted


Significance depends on a particular context that
is always open
-
endlessness


Common sense are resources

According to cognitive science



The mind is viewed as an abstractable structure
implementable in any number of possible physical
substrates


intelligence is only incidentally embodied in the
neurobiology of the human brain,


what is essential about intelligence can be abstracted
from that particular substrate and embodied in an
unknown range of alternative forms

Artificial Intelligence



People act on the basis of symbolic representation,
a kind of cognitive code,



Cognition

is not just potentially like computation
it literally
is computational



The view that intelligence is the manipulation of
symbols finds practical implementation both in so
called expert systems and industrial robots

What is a plan ?



”[…] When we speak of a plan the term will refer
to a
hierarchy of instructions


A plan is any hierarchical process in the organism
that can control the order in which a sequence of
operations is to be performed.


A plan is for an organism essentially the same as a
program for a computer […]”
Miller, Galanter and
Pribram, 1960




The
situated action

view


Focus on practice as different to the study of the
formal cognitive properties of artifacts


Unit of analysis is
the activity of persons
-
acting in
setting



The prescriptive significance of intentions for
situated action is inherently vague,


Improvisatory nature of human action


Human action is contingent



Situated action view



Every course of action depends in essential ways upon its
material and social circumstances


1
-

Plans are representations of situated actions

2
-

In the course of situated action representation occurs where
there is a breakdown

3
-
The objectivity of the situation of our action is achieved rather
than given

4
-

Central resource for achieving the objectivity of situations is
language

5
-
Mutual intelligibility is achieved in every occasion of
interaction

The problem of human
-
machine
communication


”Expert help system”


a
computer
-
based system attached to a photocopier,
intended to instruct the user


The design objective


to provide timely and relevant information to the user
regarding the operation of the copier



The system must recognize the action of the user

The expert help system

identifies ...



the user’s purposes with a job specification and the
specification invokes a associated plan


the plan is ascribed to the user as a basis for interpreting her
actions


the plan is conveyed in the form of instructions for a step
-
wise
procedure


the design assumes that there is correspondence of the
system’s plan to the user’s purposes that enables the
interaction


Which are the consequences of taking a statement of
intent and an ascribed plan as grounds for the
interpretation of situated action ?

Troubles for the resourceful user...

Plans and states

machine

Situated inquiries

Problems of understanding due to the disparity

of their respective resources


instructions

actions

The system’s resources


The machine has access only to a very small
subset of user action



i.e.Doors being opened and closed, buttons being
pushed, papers trays being filled…



The machine is watching the user’s actions
through a very small key hole, mapping what it
saw back onto a pre specified template of possible
interpretations




The user’s resources


Human interaction succeeds due not simply to the
abilities to construct meaningfulness but to the
possibility of
mutually constituting intelligibility


i.e.Detection and repair of misunderstandings



Interactive program exploits certain characteristics of
human conversation


Language of interactivity and the dynamics of
computational artifacts obscure enduring
asymmetries

that
users discover in practice

Speech acts tell us nothing further about the
significance

A
: Are you going to be here for ten minutes ?

B: Go ahead and take your break. Take longer if you
want

A: I’ll just be outside on the porch. Call me if you
need me

B: Ok, Don’t worry







(Gumperz, 1982)



How B arrives at the right inference ?

Indexicality of language


Efficiency of language lies in :


expressions with conventional meanings


its relationship to circumstances (conditional
meanings)


The indexicality of instructions means that an
instruction ’s significance with respect to action does
not inhere in the instruction but must be found in the
situation of use

The mutual intelligibility of actions


Within the normative paradigm actors share a
system of culturally established symbols and
meanings



The stability of the social world is not due to an
eternal structure but to situated actions that create
and sustain shared understanding on specific
situations of interaction


Relation of plans to situated actions


In the planning model of human interaction,


plans are mental constructs, abstractions over
action, representations of situated actions


Plans do not take sufficient account of the
situatedness of most social behaviour


The planning model confuses plans with situated
actions

Alternative account of the relation of

plans to situated actions


The foundation of action is not plans but local
interactions with the environment


The function of plans is to orient or position us, to
exploit some contingencies of our environment
and to avoid others



plans are weak resources

Critiques


Confined to the analysis of actions and operations


Slightly behaviouristic undercurrent in that it is
the subject’s reaction to the environment that
determines action


Primacy of the situation


What constitutes a situation is defined by the
researcher


Resourceful user or …. ?